16
This article was downloaded by: [University of Tasmania] On: 03 September 2014, At: 02:51 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Ergonomics Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/terg20 The importance of usability in product choice: A mobile phone case study Zoë Mack a & Sarah Sharples b a Lloyds Register , Suite 9, 11 Mill Point Road, South Perth, WA, 6151, Australia b Human Factors Research Group, Faculty of Engineering, University of Nottingham, University Park , Nottingham, NG7 2RD, UK Published online: 24 Nov 2009. To cite this article: Zoë Mack & Sarah Sharples (2009) The importance of usability in product choice: A mobile phone case study, Ergonomics, 52:12, 1514-1528, DOI: 10.1080/00140130903197446 To link to this article: http://dx.doi.org/10.1080/00140130903197446 PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions

The importance of usability in product choice: A mobile phone case study

  • Upload
    sarah

  • View
    214

  • Download
    1

Embed Size (px)

Citation preview

Page 1: The importance of usability in product choice: A mobile phone case study

This article was downloaded by: [University of Tasmania]On: 03 September 2014, At: 02:51Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,37-41 Mortimer Street, London W1T 3JH, UK

ErgonomicsPublication details, including instructions for authors and subscription information:http://www.tandfonline.com/loi/terg20

The importance of usability in product choice: Amobile phone case studyZoë Mack a & Sarah Sharples ba Lloyds Register , Suite 9, 11 Mill Point Road, South Perth, WA, 6151, Australiab Human Factors Research Group, Faculty of Engineering, University of Nottingham,University Park , Nottingham, NG7 2RD, UKPublished online: 24 Nov 2009.

To cite this article: Zoë Mack & Sarah Sharples (2009) The importance of usability in product choice: A mobile phone casestudy, Ergonomics, 52:12, 1514-1528, DOI: 10.1080/00140130903197446

To link to this article: http://dx.doi.org/10.1080/00140130903197446

PLEASE SCROLL DOWN FOR ARTICLE

Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) containedin the publications on our platform. However, Taylor & Francis, our agents, and our licensors make norepresentations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of theContent. Any opinions and views expressed in this publication are the opinions and views of the authors, andare not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon andshould be independently verified with primary sources of information. Taylor and Francis shall not be liable forany losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoeveror howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use ofthe Content.

This article may be used for research, teaching, and private study purposes. Any substantial or systematicreproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in anyform to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions

Page 2: The importance of usability in product choice: A mobile phone case study

The importance of usability in product choice: A mobile phone case study

Zoe Macka and Sarah Sharplesb*

aLloyds Register, Suite 9, 11 Mill Point Road, South Perth WA 6151, Australia; bHuman Factors Research Group, Faculty ofEngineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK

Usability has become established as an important aspect of product design. This paper describes an investigationthat was carried out to identify the importance of usability in product choice related to other product attributes.Interviews were initially carried out to identify possible attributes that contribute to product choice. Experimentswere then undertaken using the methods of active information search, structured preference elicitation, ranking andinterviews in order to find out what attributes were important to people when choosing an example product – mobilephones. It was found that usability is indeed important in product choice but perhaps not as much as usersthemselves believe. Other attributes that were found to be more important were features, aesthetics and cost. Theprocess of product choice was found to be complex and it may be the case that people have come to expect usabilityin their products. Further research is needed to understand more fully the changing role of usability in productchoice and to further improve the quality of the user–product relationship.

Keywords: usability; product choice; mobile phone; evaluation

1. Introduction

Although usability has become established as a keyconsideration in product design, there is a need toestablish its importance when it comes to productchoice. This paper presents an investigation into theimportance of usability in product choice related toother attributes such as brand, aesthetics, cost andfeatures. The study presented in this paper attempts tocompare the importance of these attributes by applyinga set of methods that examine each of these attributesin a controlled manner by using techniques to elicitopinion and preference data from participants. Theaim of this set of methods is to develop understandingof whether it is possible to isolate the relative value ofdifferent attributes when making a judgement about adevice or product.

The International Organization for Standardiza-tion (ISO) has proposed the definition of usability as:‘. . . the effectiveness, efficiency and satisfaction withwhich specified users can achieve specified goals inparticular environments’ (International Organizationfor Standardization 1994). Jordan (1998) elaborates onthis definition by describing effectiveness as the ‘extentto which a goal or task is achieved’, the efficiency beingthe ‘amount of effort required to accomplish a goal’and the satisfaction referring to the ‘level of comfort

that the users feel when using a product and howacceptable the product is to users as a means ofachieving their goals’. Although it is acknowledgedthat this definition has received some criticism (e.g.Stanton and Baber 1996, who comment that the ISOdefinition implies that usability is an empirical entitythat may not always be a suitable perspective to take)this is the definition of usability that will be adoptedthroughout this paper.

2. The growing importance of usability

If a product is not usable this can cause problemsof a varying degree of severity. Jordan (1998),Norman (1988) and Preece et al. (2002) point outthat in the past many product types ranging fromVCRs, photocopiers and hob cookers were designedwith little regard for the people who will be usingthem and their lack of usability caused frustrationand time wasting. Usability also has financialimplications for the commercial and industrial world.As Jordan (1998, 2001) pointed out, the profile ofusability has increased in recent years with moreliterature being written on the subject, more usabilityprofessionals being employed, more conferences onthe subject and a larger public awareness of itsexistence.

*Corresponding author. Email: [email protected]

Ergonomics

Vol. 52, No. 12, December 2009, 1514–1528

ISSN 0014-0139 print/ISSN 1366-5847 online

� 2009 Taylor & Francis

DOI: 10.1080/00140130903197446

http://www.informaworld.com

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 3: The importance of usability in product choice: A mobile phone case study

Jordan (2000) described the movement of usabilityfrom a ‘satisfier’ to a ‘dissatisfier’. Whereas in the pastusers would tolerate poor usability for novel functionsand performance; if the product was usable also, thiswould be seen as a bonus (i.e. a ‘satisfier’). Now buyersare taking for granted that a product will be usableand are disappointed if it is not (i.e. ‘dissatisfied’).Customers want more, they expect to be able to usetheir products effectively, efficiently and at least withsatisfaction. In fact, now that customers are startingto expect usability they now want more than justsatisfaction from their products (Jordan 1997, 2000).

Although it is generally agreed that usability is animportant attribute of successful products and interfaces(Maguire et al. 1994, Atyeo and Robinson 1995, Jordan1997, Lohse 2000, Bullinger et al. 2001), it is acceptedthat usability alone is not enough to optimise the user–product relationship. In 2003, Lingaard and Dudek(2003) commented that aesthetics, emotion, expectationand likeability as well as usability contribute to the user–product experience but these different aspects will varydepending on the type of experience. de Angeli et al.(2006) discuss this in relation to websites and highlightthe impact of interaction style on perceived informationquality, including an interaction of interaction style withaesthetics. This illustrates the breadth of impact thatdesign features can have – and the intertwined nature ofefficiency, effectiveness and satisfaction.

Tractinsky (1997) called for a more balanced,holistic approach to product design, this time withmore emphasis on the appearance and aesthetics of theproduct, claiming that an attractive appearance affectsattitudes and behaviour of the user and therefore theuser’s experience with the product. However, Over-beeke et al. (2002) suggested that there is more tousability than ease of use and that users may oftenchoose to use a product even though it is not easy touse because the product is enjoyable, challenging orrewarding to use. Whereas human factors may havebeen just aiming for ‘satisfaction’ as one of the goalsof usability (Preece et al. 2002), designing pleasurableproducts was coined as ‘the new human factors’(Jordan 2000), where enjoyment and pleasure areconsidered important in the user–product relationship.Rather than considering products as tools with whichhumans complete tasks, they are thought of as ‘livingobjects with which people have relationships’ (Jordan2002). ‘Ease of use’ has also developed as a concept andis changing into ‘joy of use’ (Hassenzahl et al. 2001).

2.1. Existing research into the importance of usabilityin product choice

A number of studies have attempted to examinethe importance of usability in product choice. The

following section summarises a selection of thestudies and identifies the trends that have beenobserved in relationships between product features,along with the challenges associated with examiningthe relative impact of different, intertwined productfeatures.

Several studies have suggested that other featureshave priority over usability in product choice. Jordanand Thomas (1995) adopted a ‘willingness to pay’paradigm to evaluate the comparative level ofimportance that users attached to three differentattributes of a product that incorporated a printer.They found that print quality was the mostimportant, with ease of loading (the attribute mostclosely related to usability in this context) the leastimportant. Lightner (2003) examined the relativeimportance of usability in the context of e-commerceby considering the preferences that users reported ofthe various characteristics of online shopping sites.It was found that, in this context, security (i.e. of datahandled by the site), information quality (i.e.perception of whether information contained in thesite was perceived as true or reliable) and informationquantity (i.e. the amount of information suppliedabout the particular product being purchased) wereconsidered most important to users. Next inimportance were price, navigation, buying speed andreputation of the vendor. Lightner (2003) suggestedthat this indicated the ‘usefulness’ of the site wasmore important than aspects of the site related to‘usability’ (in this context probably most closelyindicated by ‘buying speed’). However, Maguire et al.(1994) report that ease of use was seen as veryimportant by consumers purchasing electronic homeproducts and was given priority over advancedfeatures by all participants except those in youngerage groups. In a questionnaire-based survey, Maguire(2004) showed that functions and style representedthe strongest factors in users’ liking of a product,although usability also played an important role on asmaller scale. Usability seemed more important thanstyle, however, in terms of people’s dislikes, perhapsimplying that absence of usability has more impactthan presence.

Norman (1988) and Rohlin (2002) both highlightthe practical difficulty in assessment of usability of adevice during product purchase. Norman notes thatbuyers do not normally have the opportunity to carryout many tasks with a product whilst in a shop andthat it is hard to assess product usability simply bylooking at a product. Rohlin expands on this andsuggests that, partly as a result of this, consumers areonly able to apply usability criteria in a verysimplified form. Rohlin suggests that it does notmatter how user friendly a product actually is during

Ergonomics 1515

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 4: The importance of usability in product choice: A mobile phone case study

active use, the customer will not buy the productunless it expresses user-friendly attributes straightaway and in a clearly observable manner. This alsosuggests that if a user does consider usability to beimportant, they may use prior knowledge, e.g. frommarketing, previous experience with a brand orrecommendation from a friend, to gain theirinformation about usability when selecting a product.

Work by Davies (2002) and Han and Hong (2003)has illustrated the importance of a product’s look inpurchasing decisions. Davies (2002) carried out ausability test to discover which phone users wouldpurchase out of two tested. It was found that, initially,before being used, all six users chose the same phonebecause the ‘look’ of it appealed to them. However,when participants had the opportunity to actually usethe phones to carry out specific tasks they changedtheir minds and chose the second phone due to itsease of use, screen quality and phone build quality.This illustrates that, after a period of use, aspectsof phone design related to usability do becomeimportant, but that these features may not be initiallyobservable. Han and Hong (2003) asked participantsto rate audio/visual equipment features’ importanceand established a link between these features andoverall product attributes. These features were domi-nated by aspects of the look and feel of the product,with features such as degree of curvature usage by thebody of the product and surface roughness beinghighlighted. Other features that could be interpretedas related to usability, such as identifiability of controlsymbols, or functionality, such as number of controls,were also found to have significant influence onoverall product design properties. Diefenbach andHassenzahl (2009), however, illustrated that usabilitydoes, on occasion, outweigh the inherent attractivenessof ‘looks’.

Several studies have highlighted the interactivenature of different product features and the difficulty,therefore, in isolating their relative importance. Sevaet al. (2007) considered the impact of productattributes on users’ emotions in the context of thecommercial market, using mobile phones as testproducts. They identified that the attributes thatcontributed to emotional experiences, such as feeling‘amazed’, ‘content’ ‘encouraged’ or ‘hopeful’ wererelated to the phone’s dimensions and the relationshipsbetween these dimensions. Hassenzahl (2004) specifi-cally examined the relationship between perceivedusability, ‘hedonic attributes’ (referring to aspectssuch as ‘cheap to valuable’, ‘lame to exciting’ or‘standard to creative’) and user satisfaction, using MP3player interfaces as a sample technology. He identifiedthat ‘goodness’ (equivalent to user satisfaction) de-pended on both usability and hedonic attributes. Park

et al. (2006) specifically examined the effect of trust oraffection for a specific brand on usability and foundthat participants reported lower mental and physicalload when operating products for which they had apre-existing preference, but results relating to therelationship between usability and brand image werenot conclusive. Of course, this could be a consequenceof the likelihood that as users use a product of a certainbrand they become familiar with and trust it, so it isthe familiarity, or even previous perception of usabilitythat breeds this trust. McNamara and Kirakowski(2006) highlighted the three areas of functionality,usability and user experience (referring to the user’spersonal experience of using the product and thesubjective feelings they hold after this experience).They illustrate the interactive and subjective nature ofthe concept of usability, stating ‘someone . . . may wellagree that the usability of their interface is awful, buttheir experience may be very immersive andcompulsive’.

Isiklar and Buyukozkan (2007) and Han et al.(2004) both specifically considered mobile phonefeatures and their interrelationships. Isiklar andBuyukozkan (2006) compared the different weightingsof characteristics such as physical characteristics,technical features, functionality, brand choice and‘customer excitement’ and found that functionalitywas the most preferred factor for all three phonesexamined, with ‘customer excitement’ and basicrequirements being identified as least influential.Han et al. (2004) developed empirical models to linkdesign features to overall satisfaction and‘luxuriousness’, ‘attractiveness’ and ‘harmoniousness’.They found that a number of design featurescontributed, including phone size and weight, colour,material, button shape and interface features, but didnot attempt to isolate ‘ease of use’ or ‘usability’ as afeature.

This literature highlights a number of points. First,the different aspects and features of mobile phonesinteract and it is difficult to isolate their relativeimportance. Second, there is a high dependence onsubjective report data and there is a need to structurethis in order to understand the difference between whatpeople report that they feel are important factors inproduct purchase and what are actually importantfactors, either during purchase or after a short periodof use of a product. Finally, there is some evidence thatpeople are influenced by brand and aesthetics, so itmay be particularly important to isolate these factorsin any structured user preference elicitation technique.As usability is a key factor in a product’s successfuluse, an important question is what role does this playin the mix of influences that determines a person’sproduct choice?

1516 Z. Mack and S. Sharples

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 5: The importance of usability in product choice: A mobile phone case study

3. Developing a methodology for comparison of

importance of product attributes

This paper presents a study that considers howimportant usability is to those who choose products,where it falls in comparison to other factors and whatthose other factors are. By combining the informationfrom the literature and an informal series of interviewswith five experts in human factors and mobile phoneuse, nine attributes were identified as being potentiallyimportant in product choice (see Figure 1).

It was then necessary to develop new or adaptexisting methods to investigate the importance ofusability in product choice and how it relates to othercontributing product attributes. There is no standardpractice for investigating what people are influencedby during product choice. The first stage of thismethod development process was to identify anexemplar product that could be used as a basis forasking participants questions regarding influences onproduct selection in a concrete context (as recom-mended by Jordan and Thomas 1995). Mobile phoneswere selected as the example product, due to their highlevel of ownership at the time of the study (approx.80% in the UK – Crabtree et al. 2003) and the varietyof models available. Other studies (e.g. Han et al. 2004,Isiklar and Buyukozkan 2007) have successfully usedmobile phones as example products in studies of thisnature. Whilst it is acknowledged that there are otherfactors associated with mobile phone purchase, such ascontract type and network preference, participantswere instructed to disregard influences from thesefactors and assume that they could get any networkservice or contract they wished on the phones inquestion.

The first method was active information search(AIS). This method was developed by Huber et al.(1997) to investigate peoples’ decision-making process.It involves giving the participant a minimal description

of the decision situation and the participant thenasking the experimenter questions in order to obtainmore information to make their decision. Thequestions are then analysed using content analysis.Little past work was found where this method has beenused but it is a simple approach to finding out whatpeople consider important when making a particulardecision and was considered an appropriate methodfor this purpose. Huber et al. (1997) state thatAIS is a promising technique but recommended that itshould be complemented by other techniques(e.g. using triangulation; Robson 2002) whenused as not everything in the decision process iscaptured. Therefore, this study uses multiplemethods.

The second method was structured preferenceelicitation (SPE). This method was based on theprinciples of user trials, such experiments involvingpeople have become an established method ofmeasuring interaction between user and product withinthe human factors community (McClelland 1995). Theaim of SPE was to review the different influentialfactors on product choice in a systematic manner, toenable the identification of the different choices thatparticipants might make for each different factor(although this does preclude examination ofinteractions between factors). The SPE user trialsinvolved the separate presentation of different elementsof the devices (e.g. interface only, size and weight onlyfollowed by the completion of subjective responsescales). However, it became apparent that the SPEalone might not be enough as not all the identifiedproduct attributes could be tested separately. Forexample, aesthetics and brand are difficult to separatein the presentation of an actual, rather than fictitious,product, due to the integral nature of logos or branduse of colours, styles and fonts.

Therefore, a third method, comprising simpleranking of the importance of the product attributes tothe participants was included. This is a quick andsimple technique and allows an overall ranking of theattributes to provide the order of importance of theattributes explicitly given by participants. It isgenerally accepted that participants are able to rank upto nine items reliably (Sinclair 1995); the number ofattributes considered in this experiment was nine andtherefore fits within this limit. Whilst this approach isdependent on participants understanding the terms in aconsistent way, the words describing the factors werechosen to be as clear and unambiguous as possible andstandard definitions of each term were given to allparticipants.

Finally, a small number of questions was includedto obtain extra background information about thereasons for choosing their current phone, whichFigure 1. Attributes contributing to product choice.

Ergonomics 1517

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 6: The importance of usability in product choice: A mobile phone case study

formed the bases of a fourth method called ‘currentphone justification’.

An outline of the different methods used and theattributes presented can be seen in Figure 2.

A within subjects design was applied. Due to thenature of the methods and the results obtained, thisstudy was highly qualitative; statistical significance wasnot therefore examined, with the exception of somenon-parametric analysis of ranking data.

Within the SPE, a particular aspect of usability –visual interface usability – was considered. Thisenabled the isolation of aspects of the interface, suchas menu and label wording and screen layout, but didnot encompass the interaction between visual interfacedesign and keypad/phone screen interaction.

4. Method

4.1. Participants

Participants were recruited through contacts ofthe author and were paid £8 each. A total of 31participants were recruited via personal contacts ofthe experimenters. All participants owned and usedmobile phones. The participants spanned a range ofmobile phone use – two participants were currentlyusing their first mobile phone, but all others hadpreviously owned at least two different mobile phones.In total, 12 participants were male and 19 werefemale, the average age of the participants was justover 28 years, with a range of 18–59 years. Studieswere conducted in a participant’s own home or

workplace and each session lasted approximately45 min.

4.2. Materials

Three mobile phone designs were used as the basis forall of the attributes within the study. These wereselected to be representative of the types of phonesavailable at the time and also varied in the types offeatures, interface style and shape.

Phone A was a standard ‘candy bar’-style phone,dimensions 103 mm 6 45 mm 6 17 mm, weight82 g; phone B was a flip phone, dimension84 mm 6 45 mm 6 23 mm with an aerial length27 mm, diameter 8 mm and weight 83 g; phoneC was also a flip phone, dimensions80 mm 6 25 mm 6 40 mm with an aerial length22 mm, diameter 8 mm and weight 102 g. All phoneshad bi-colour displays.

A laptop computer was also used to display anumber of the attributes and to run a program thatmocked up the mobile phone interface. Models of thephones were also used to mock up the size and shape(discussed in more detail later). An example of themocked up interface is shown in Figure 3.

The phones were labelled A, B or C throughoutthe experiment and presented in a different order foreach attribute and for each participant, usingrandom numbers generated and applied to the sixpossible orders of presentation of each attribute foreach participant.

Figure 2. Outline of methods used.

1518 Z. Mack and S. Sharples

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 7: The importance of usability in product choice: A mobile phone case study

4.3. Procedure

4.3.1. Active information search

A scenario was described to the participants wherethey were in a mobile phone shop and wanted topurchase a mobile phone. They were offered anexample phone and were required to decide whetheror not they wanted to purchase that phone. The onlyway of finding out anything else about the phone wasto ask the salesperson (role played by the experimen-ter) questions about the phone. Participants were notallowed to handle the phone that they were consideringor see any pictures or models of the phone duringthe AIS process. An example of a question asked bythe participant might be ‘is the phone easy to use?’ –this would be classified as referring to usability. Thequestion ‘how big is your phone’ would be inferred asreferring to size.

This is similar to a scenario that an individualmight actually face when buying a mobile phone, inthat they may go into a shop and ask questions aboutthe various phones they have in the shop in order tofind out more about the phones available and narrowdown the selection. It was important to get a balance inthe information given to them in the description of thescenario and the answers given, as too much mayinfluence the participant and too little would leave theparticipant confused.

The answers given to participants’ questions by theexperimenter were short and positive so that theywould keep asking questions rather than deciding theydid not want the phone early on. ‘Yes’ and ‘no’answers were given as much as possible. For questionsabout cost, participants were informed that a variety of

tariffs, networks and, thus, handset costs wereavailable.

The participants were instructed to ask as manyquestions as they could until they ran out of questionsor had enough information to make a decision. Allparticipants were required to ask at least threequestions. Their questions were then categorised intothe various attributes using content analysis (Robson2002) to establish how important the attributes were bycounting how many participants mentioned eachattribute. Content analysis is a method that isappropriate when, as in this case, it is possible to pre-assign some categories and those categories arereasonably structured in nature. Robson (2002) alsonotes that it is unobtrusive and supports reliabilitychecks well. Miles and Huberman (1994) also note thatit is appropriate when the ambiguity in participantresponses is low and categories are well defined.

4.3.2. Structured preference elicitation procedure

SPE consisted of a set of isolated attributes of the threephones being presented in a pre-defined order. Aftereach attribute was presented, the participant was askedto name their least and most preferred phone on thatattribute, yielding a rank ordering of phones for eachattribute. The order of attribute presentation duringSPE was carefully chosen, as a certain amount ofinformation about the phones was being revealed tothe participants each time they tested an attribute. Forexample, the participants might recognise the phoneswhen shown their aesthetics and, therefore, knowledgethat they already had about the phones from the realworld could have influenced their decision from thenon. Therefore, the first attribute was the oneconsidered by the authors to be the least revealingabout the phones, and attributes were introduced oneby one, with the ones thought most likely to reveal thephone brand and type kept until later in the SPEprocess. The order of presentation of phone attributescorresponds to the order in which the results arereported in the following paragraphs a) to f).

For each attribute, participants were asked to statetheir preference for each model and give reasons fortheir choice. Therefore, for each attribute, the threephones were ranked first, second or third and a writtennote made of their choice by the experimenter.

(a) UsabilityIn order to allow users to judge interfaceusability without seeing the phone, a programwas designed using Microsoft PowerPoint (asshown in Figure 3) that allowed users tonavigate through replicated menus of thephones using a mouse and the ‘action buttons’

Figure 3. Example of mocked-up interface displayed onlaptop.

Ergonomics 1519

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 8: The importance of usability in product choice: A mobile phone case study

on PowerPoint. The slides were designed in sucha way that the style of each interface appearedsimilar to the others so it was not immediatelypossible to identify what brand of phone wasrepresented – the differences between theinterfaces (i.e. the isolated attribute) were menuwording and keypad/screen layout. After theperiod of use of the mocked-up interfaces,participants were asked ‘which phone would beyour first choice to buy in terms of usability?’and ‘which phone would be your last choice tobuy in terms of usability?’.The first task completed by the user was to makea call to the same person for each phone. Thesecond task was to find a specifiedmenu; this wasto allow the participant to become familiar withthe navigation of the interface and allow them tojudge the usability more accurately.An objective measure of the usability was alsorecorded. The time taken to call ‘Sam’ wasrecorded for each phone and the number oferrors that occurred when performing the taskswas also recorded. Performance of the task wasrecorded on audio cassette and was timed fromthe tape at a later date. The experimenter alsonoted any behaviours of interest during the tasks.

(b) Size and weightThree replica models of the phones’ shapes andweights were manufactured from aluminium(see Figure 4). Both size and weight weremanipulated to be the same as the actual phonemodels. These replicas were finished to attemptto soften the edges of the model to make themas close to the actual shape of the phones aspossible, despite the different materials used(aluminium of the model compared to mouldedplastic of the phone).The participants were presented with the threephones at the same time and were allowed to

handle them. Again, and in all subsequent SPEstages, participants were asked to state whichphone would be their first or last choice, takinginto account the isolated attribute underconsideration.

(c) Marketing profileThe aim of the marketing profile was to presentinformation about the phones’ reputation inthe technical media, aiming to address the ‘coolfactor’. Short reviews were selected from trademagazines and were presented to theparticipants in written text on a computerscreen. The reviews were selected to be ofequivalent length and similar sentencestructure.

(d) FeaturesThe features (or the functions) of the phonesare what the phone can actually do. These werelisted in a matrix that indicated whether eachphone had that particular feature or not.

(e) AestheticsPhotographs of all three phones were shown tothe participants at the same time on thecomputer screen. The participants were askedto try to base their decision on looks only andto try to ignore brand preference if theyrecognised the phones from the real world.

(f) Combined attributesThe participants were then shown all theattributes of each of the phones to allow themto make a decision about which phone theywould like overall when they knew whichattributes belonged to which phones. At thispoint handset cost (for equivalent service plans)was also included.The participants were also asked if theyrecognised any of the phones at any point inthe experiment and if they thought it hadinfluenced their earlier answers.

4.4. Attribute ranking

Nine cards, each with an attribute and a briefconsistent explanation of that attribute, weresimultaneously presented in front of the participants.The participants were then asked to sort the cards ina line in order of importance when they came tochoose a new phone. The order was then noted andparticipants were asked to explain why the firstattribute was the most important to them and ifthere was anything that was important to them thatwas missing; this enabled identification of anyattributes not explicitly included in the attributeranking list.

Figure 4. Aluminium models of the phones’ size andweight.

1520 Z. Mack and S. Sharples

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 9: The importance of usability in product choice: A mobile phone case study

4.5. Background information

The participants were then asked questions about theirown phone use and some descriptive data wereobtained.

5. Results

For clarity and brevity, a summary of key results onlyis presented here. Percentages are reported throughoutto enable comparison of results across the differentmethods. However, it is acknowledged that these canbe misleading with small sample sizes; therefore, theabsolute numbers of participants involved are alsonoted. The data relating to separate attributes from theSPE are presented in section 5.5.

5.1. Active information search

All participants asked at least three questions in orderto be able to reach a decision about purchasing themobile phone. A total of 27 (90%) participants asked afourth question and any questions asked after thefourth were grouped together.

The questions were analysed and a standard ‘countbased’ content analysis was carried out. The results ofthe active information task are presented in the sameway as in Huber et al. (1997). The percentage ofparticipants who asked at least one question about therespective product attribute can be seen in Figure 5.

The graph shows that 28 (90%) participants askedabout the features of the phone, with size also beingasked by a high proportion (n ¼ 22, 71.1%). Usabilityof the phones was asked about by nearly one-third ofall participants. No participant asked about mediareviews or fashion.

When the order of the questions was examined, 12(40%) participants asked about the size of the phonefirst and only one participant asked about usability astheir first question.

5.2. Structured preference elicitation

Participants were asked to choose their overallpreference of phone at the end of the SPE after allattributes were revealed. A content analysis wasperformed and the same category system as used inthe AIS was used. For example, one participant’sreasons for choosing a phone were ‘good looks, easy touse, good shape and size, everyone knows how to usephone A’. So this participant’s response would becategorised as: aesthetics; usability; size and brand.The category ‘other’ contained comments such as ‘I amfamiliar with this phone’, ‘I want to try somethingdifferent’ and ‘it has good technology’.

Figure 6 shows the percentage of participantswho mentioned each particular attribute as being areason why they chose the phone that they wouldpurchase after all attributes of the phones wererevealed.

Figure 6 shows that usability was the attributementioned most by participants (n ¼ 17, 54.8%) asinfluencing their decision about which phone to chooseout of the three overall, closely followed by cost(n ¼ 15, 48.4%). Fashion was not mentioned by anyparticipants. These results are inferred to indicate theparticipants’ explicit beliefs about their perceivedimportance of usability and are compared with thematch between phones chosen according to interfaceusability and overall phone preference later in thissection.

In the final stage of the SPE, participants wereasked whether they recognised any of the phonesinvolved in the trials before the photographs wereshown at the aesthetics stage. Table 1 shows the detailsof this.

A total of 22 (71%) participants recognised one ormore of the mobile phones on which the SPE wasbased. However, only three of these participantsbelieved this affected their answers throughout theSPE. Five of the participants who thought theyrecognised the mobile phones were in fact incorrect;they believed they had recognised particular phones atthe user interface stage but the mock up seemed to‘fool’ them.

5.3. Ranking task

The median rankings of the attributes ranked inorder of importance to the participants whenbuying a mobile phone are shown in Table 2.

Figure 5. Percentage of participants who asked at leastone question about each attribute during activeinformation search.

Ergonomics 1521

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 10: The importance of usability in product choice: A mobile phone case study

The smaller the number the higher the rank, asshown in Table 2, cost and usability are rankednumber 2 so were considered the most important;fashion and media reviews were the least importantto participants as their median ranking is eighth. AFriedman test revealed an overall significant effectof attribute on ranking (X2 ¼ 109.6; degrees of free-dom ¼ 8; p 5 0.001). Post hoc analyses identifiedhomogeneous subsets of usability and size, usabilityand cost, features and size, aesthetics, weight andbrand and fashion and reviews.

When asked if there was anything important tothem that was missing from the given attributes in theranking task, five participants said there was some-thing missing and that these missing attributes camenear the top of their list of importance – commonlymentioned features included durability and networkcoverage.

Table 1. Participants who recognised one or more phones during structured preference elicitation (SPE) (before they wererevealed).

Number of participantswho recognised oneor more phones

Number of participantswho incorrectly recognised

phones

Stage of SPE phone wasrecognised

Number of participantswho believed it had affected

their answersStageNumber ofparticipants

22 (71%) 5 (16%) Usability 17 (55%) 3 (10%)Size/Weight 5 (16%)Reviews 1 (3%)

Table 2. Median rankings of importance of attributes to participants when choosing a mobile phone.

Usability, cost Features Size Aesthetics, weight Brand Fashion, reviews

Median rank* 2 3 4 6 7 8

*1 ¼ highest; 9 ¼ lowest.

5.4. Background of participants

Figure 6 shows the different attributes that participantsmentioned as being one of the reasons that theypurchased the mobile phone they currently owned. Thecontent analysis was performed and the attributes werecategorised.

The category of ‘media reviews’ was interpretedas referring to reviews by official sources, such asspecialist magazines, but was also based on influencesfrom friends and family; for example, if a participantsaid ‘a friend had it’. Comments included in the ‘other’category were durability, if the phone was passed on tothem for free by someone they knew or if it was similarto their old phone. One participant had no choiceabout the phone they had as it was given by theorganisation for which they worked. One participanthad two mobile phones, one for work and one for

Figure 6. Participants who mentioned each attribute as a reason for their overall choice of phone during structured preferenceelicitation.

1522 Z. Mack and S. Sharples

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 11: The importance of usability in product choice: A mobile phone case study

personal use; only the phone they chose themselves wasconsidered.

Figure 7 shows that 16 (50%) participants men-tioned cost as being one of the reasons for purchasingtheir current phone, with features also being impor-tant. Usability was only mentioned by five (16%)participants as contributing to the decision.

5.5. Comparisons of attributes

After detailing the raw results from each stage of theexperiment, this section compares data within eachstage to obtain information about relationships thatmay exist. The findings from the different experimentalmethods are also compared to enable comment on thesuccess of the different methods used.

5.5.1. Combined attributes selection agreement withindividual attributes

At the end of the SPE, participants were asked tostate which of the three phones they preferredoverall. These data are then compared with how they

rated each phone for each attribute during the SPEmethod.

If an individual attribute does not stronglyinfluence the final combined attributes selection (phoneselection) then it would be expected that the percentageagreement between the two choices would be low.Conversely, if an individual attribute has a high impacton the combined attributes selection then thepercentage agreement would be high.

Figure 8 shows that the higher the percentage, themore important that particular attribute appears to beto the participants. As can be seen, the highestpercentage of agreement was with the features of thephone (n ¼ 16, 51.6%). This indicates that featuresmay be the most important attribute when choosing amobile phone. Aesthetics also had a similar percentage(n ¼ 15, 48.4%) of agreement.

When considering interface usability, the majorityof participants (n ¼ 19, 61.3%) did not choose thephone that they perceived had the most usableinterface as their first choice to buy overall, suggestingit is not the most important attribute to them whenchoosing a mobile phone. In fact, nearly one-quarter

Figure 7. Reasons given for selection of participant’s current phone.

Figure 8. Participants who chose the same phone overall as they did for individual attributes during structured preferenceelicitation.

Ergonomics 1523

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 12: The importance of usability in product choice: A mobile phone case study

(n ¼ 7, 22.6%) of participants chose their first choiceof phone overall despite it being the phone whoseinterface they found the least easy to use. As there werethree phones, if the impact of usability was random, a33% agreement would be expected, so the actual 38%agreement is unlikely to indicate a major influence ofinterface usability on overall phone choice. This maybe due to the fact that only a ‘virtual’ interface wasconsidered during the usability element of the SPE – inactual phone purchases usability may also encompassaspects such as the ease of pressing buttons, opening aflip-type phone or completing other interface tasksnot considered within the simple example. It may bethat other tasks or phone designs would have led toa greater difference in perceived usability. If suchdifferences existed, the impact of usability on overallphone selection may have been different.

However, interpretation of these subjective resultsis difficult as the cost of the phones may haveconfounded the responses given. Some participantsmentioned that they would choose a different phone ifthe cost was lower, especially one that was priced atalmost double the price of the cheapest phone. Out ofthe 19 participants, 12 (63.2%), whose usability choiceand overall choice differed, mentioned cost as being areason for their first choice overall. This finding maybe indicative of the interactive nature of the attributesconsidered.

5.5.2. Performance and perceived usability

Performance and perceived usability were comparedby considering participants’ behaviour at the usabilitystage of the SPE. Time taken for a participant to callsomeone in the phone book for each phone was takenas the performance measure and the phone thatparticipants chose as being the most usable was theperceived usability. The number of errors made wasalso recorded but as the task was a short and simpleone many of the participants made no errors with anyof the phones so it was felt not to be a useful indicationof performance in this situation.

The time for the second task (menu search) couldnot be used to objectively compare performance as thetasks for the three phones were not identical and didnot require the same number and type of steps, but

they did allow the user to get more familiar with usingthe mock up and therefore make a better judgement onthe usability.

The performance times on task 1 were compared tothe phone that the user selected as their preferredchoice after carrying out the usability tasks on theinterface mock up. The percentage of participantswhose perceived usability (preferred phone in termsof usability) was the same as the phone with bestperformance for them (phone with quickest time forthem) was calculated to find if there was a differencebetween the two. If two of the phones scored thesame in performance and one of them was chosen inthe perceived usability, it was taken that theperformance in terms of usability and perceivedusability were the same because they still chose aphone that was one of the two most usable phonesfor them.

In total, 38.7% (n ¼ 12) of the participantsperformed the task fastest with the phone that theyselected as being their preferred choice whenconsidering usability only – only slightly higher thanthe 33% agreement that would be expected by chancealone.

5.5.3. Current phone owned compared to first choicemade for usability and overall

In order to establish whether responses wereinfluenced by the phone owned currently byparticipants, choices with regard to interfaceusability and overall were compared. Not allparticipants owned one of the three phones beingtested. However, as shown in Table 3, out of the 29participants who did have one of the three phonebrands being tested, nearly half the participants’(44.8% n ¼ 13) first choice phone in terms of usabilitywas the same brand as the phone they owned. Thiscorresponds with the fact that it was identified that48.3% (n ¼ 15) of participants mentioned familiarityas being a reason why they chose the particular phoneas the most usable. However, for the first choice thatparticipants made overall when all attributes wererevealed, only 34.5% (n ¼ 10) of participants chosethe same phone overall as the phone brand theyowned.

Table 3. Number percentage of participants who chose the most usable phone the same as their own phone brand and theirfirst choice overall the same as their own phone brand.

Percentage of Participants

First choice for usability the same as current phone First choice of phone overall the same as current phone

Yes (13) 44.8% (10) 34.5%No (16) 55.2% (19) 65.5%

1524 Z. Mack and S. Sharples

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 13: The importance of usability in product choice: A mobile phone case study

5.5.4. Other attributes identified as contributing tomobile phone choice

There were other attributes mentioned by participantsthrough each stage of the experiment. Of all ‘other’attributes, durability was mentioned the most, withfamiliarity or aspects of familiarity (i.e. ‘similar to oldphone to use’, ‘same as old phone’) also beingmentioned a number of times.

5.5.5. Comparing the findings from each experimentalmethod

Due to the different methods used, the results cannotbe compared directly but in order to consider themerits of each different method (AIS, SPE, rankingand interview) the results they produced in relation toeach other are considered.

In order to compare the results from the variousmethods, the relative importance of each attributewhen choosing a phone is listed in Table 4. In order todo this, the attribute is rated as high, medium or lowimportance depending on whether its mean rating wasin the top third, middle third or bottom third of thedata for each method.

Table 4 shows that ‘features’ was found to be ofhigh importance in all methods, with cost also beinghigh most of the time. Aesthetics was also quiteimportant, with high and medium importance placedon it. Usability of the user interface varied inimportance, being low in the AIS and justification ofcurrent phone purchased, medium in the SPE and ofhigh importance when participants justified theirreasons for their overall choice in the SPE and in theranking task. Size also varied in importance for thedifferent methods as did brand, but it was slightly lessimportant than size. Reviews and weight were lessimportant overall and fashion was found to be of lowimportance for all methods.

Other attributes were mentioned throughout theexperiment as being important to participants. Due tothe grouping of these ‘other’ attributes, it is notpossible to establish the importance of each individualextra attribute but it is possible to get some idea of howimportant these other attributes as a group are. In theAIS and SPE, ‘other’ attributes came relatively low inimportance but in the interview ‘other’ attributes werementioned more than size, brand, usability, reviews,weight and fashion as being one of the reasons forpurchasing a current phone.

6. Discussion

The main findings are outlined below.

When people are explicitly asked about usability theystate that they consider it is important

In the ranking task, participants gave usability, alongwith cost, the highest ranking of all attributes, yet whenquestioned in less explicit ways usability was notspontaneously mentioned as often as other attributes.Therefore, it may be appropriate to explicitly illustrate‘good usability’ in a product to capture the attention ofthose who claim to prioritise this attribute. This might bedone by visually demonstrating a task being completedeasily, highlighting positive reviews of usability fromusersor even providing data comparing numbers of errorsmade using one device compared to its competitors.

When people are not prompted specifically aboutusability, whilst they may still mention it, it is not theattribute given the highest priority – cost, aesthetics andfeatures are more important

In the AIS, 29% of participants mentioned attributesclassified as related to usability, compared with 90%who asked about features. Jordan (2000) described

Table 4. Importance of each attribute for each method.

AIS SPEOverall Choicejustification

Attributerankings

Current phonejustification

Features high high high high highUser Interface low medium high high lowCost medium high high highAesthetics medium high high medium mediumSize high low medium medium mediumBrand medium low low mediumReviews low medium low low lowWeight low low low medium lowFashion low low low lowOther figure/tablecontaining data

Figure 5 Figure 8 Figure 6 Table 2 Figure 7

AIS ¼ active information search; SPE ¼ structured preference elicitation.

Ergonomics 1525

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 14: The importance of usability in product choice: A mobile phone case study

the movement of usability from a ‘satisfier’ to a‘dissatisfier’. This idea is supported by the results fromthe AIS and the reasons given for buying currentphones; as usability was not mentioned it could beconcluded that participants expected it. However,when actually choosing between the differentattributes in the SPE, attributes other than usabilitytook priority. This would suggest that usability mightnot actually be as important to users as first thought.

The phone on which participants completed the sampletask most quickly was also the one rated as being themost usable

In total, 61% of participants chose phone A as beingmost usable in the SPE, and 48% performed task 1more quickly using phone A. This result implies thatwhen the entire dataset is considered there iscommonality between a user’s perception of usabilityand their performance. This emphasises the role ofefficiency in usability but defining usability was notthe purpose of this study; therefore, it is possible thatnot all potential influences on usability (e.g. keypaddesign) were considered. However, this relationship isnot clear cut, as only 38% of participants performedfastest on the phone they rated as most usable,although speed of performance was not stressed toparticipants.

Familiarity is important for both perceptions of usabilityand product choice

When participants were asked to choose the phone theyfelt was the most usable in the user trials, nearly half ofthem chose the same brand of phone that they currentlyowned. Consequently, nearly half of all participantsmentioned familiarity as a reason for their choice.Familiarity was also identified as being one of the ‘other’attributes that may be important to people whenchoosing a phone. This agrees with Khalid (2001), whonoted that people tend to prefer what is familiar.Research by Maguire et al. (1994) into the importanceof usability to customers during the buying process ofelectronic home products also found that the majorityof people attach at least some level of importance tofamiliarity when buying a product. Familiarity and itseffects on usability and product choice need furtherconsideration as it was not investigated in enough detailhere to draw any firm conclusions.

6.1. Methodological considerations

As this study presents a number of methods that havenot previously been used in this context, it is importantto analyse their success.

The application of the AIS method was successful.It was user led and did not prompt as to the purposeof the study in any way. Data obtained were richbut the method of analysis used yielded quantitativedata that allowed clear comparison with other tools.Overall, the method was quick and simple to apply andanalyse. However, it is not known if the order in whichthe questions were asked affects priorities. Also, themethod was very dependent on the level of articulationof the respondent so it was difficult to apply to someparticipants who were less outgoing. AIS also does not,however, give insight into why participants askedquestions as they did, so if this information is requiredthen it should be used in conjunction with other, moredirected questioning methods, such as interviews.

With the SPE, the forced choice nature of themethod yields simple, quantitative data. It also reflectsthe real-life scenario of having to make an actualselection. The main advantage of it was the potential toisolate the different attributes and thus obtain specificpreference data for each attribute. One problem is that,due to the likelihood of participants already beingfamiliar with some mobile phone types and brands,although attempts were made to isolate the attributes insome cases, this may not have been 100% successful.For example, when showing aesthetics information itwas difficult to remove all cues regarding product brandand size. In addition, it was not possible to examineinteraction between attributes using this method.

Order of presentation of attributes is veryimportant as it is possible that participants will guesswhich product is which as the trial proceeds. Aconsequence of this is that once a participant hasguessed (either correctly or incorrectly) the make ortype of the phone, other attributes such as brand maybias responses. SPE may be particularly valuable inassessment of new products, where brand andfamiliarity attributes may be easier to conceal.

Ranking of importance of attributes is anestablished method that is simple but very dependenton participants’ compliance and currentunderstanding. As it is an explicit questioningtechnique, it is much more susceptible to beneficialsubject bias where participants may, by this point,suspect that usability is of key interest in this study andthus rank it more highly. It is also susceptible toconformity bias where participants may desire toappear ‘cool’, such as by not wanting to seem vain byselecting aesthetics as being important.

There were limitations in this study other thanthose associated with each method. The only productconsidered throughout was mobile phones; therefore,the results can only be applied with certainty to thisproduct, a wider range of products need to be includedin future work in this area. The findings here may be

1526 Z. Mack and S. Sharples

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 15: The importance of usability in product choice: A mobile phone case study

comparable to other mobile devices, for example,but further work would be needed to understandfully the transferability of results. A larger sample ofparticipants with more age groups may also producedifferent results. Familiarity appears to be somethingpeople prefer so the fact that many users recognisedparticular phones at the usability stage of the SPE mayhave biased their choice.

It may have been wise to determine what partici-pants used as their definition of usability. This is aconcept that may mean different things to differentpeople. Therefore, obtaining some idea of what peopleconsider usability to be may have been beneficial.

This research was highly qualitative with noindication of whether any differences in the levels ofimportance placed on product attributes were actuallystatistically significant.

7. Conclusions

In conclusion, when explicitly questioned, users reportthat they consider usability to be important but, inactual fact, other attributes, particularly cost, aes-thetics and features, may well be more of a prioritywhen it comes to product choice. The research andexperimental work in this study is an initial considera-tion of the importance of usability in product choiceand how that relates to other product attributes.Factors such as age, gender, lifestyle and product typeare likely to affect the level of importance placed onusability and the other product attributes.

Further work is needed in order to understandmore fully the changing role of usability in productchoice and to develop methods to support this work.This will enable the user–product relationship to beimproved further and the relationships betweendifferent product attributes on product choice to bemore clearly understood.

Acknowledgements

The authors would like to thank the Ergonomics Society intheir support for this work in awarding Zoe Mack the UlfAberg Prize for Best Postgraduate Student project in 2005.The authors would also like to thank the anonymousreviewers for their constructive and detailed criticisms ofearlier drafts of this paper.

References

Atyeo, M. and Robinson, S., 1995. Delivering competitiveedge.Human Computer Interaction – Interact 1995, 27–29June, Lillehammer, Norway, 384–385.

Bullinger, H.J., et al., 2001. Analysing emotional impacts onacceptance of the HMI inside cars. In: M.G. Helander,H.M. Khalid, and M.P. Tham, eds. Proceedings of theinternational conference on affective human factors design,27–29 June, Singapore. London: Asean Academic Press,47–52.

Crabtree, J., Nathan, M., and Roberts, S., 2003. Mobile UK.Mobile phones and everyday life [online]. Available from:http://www.theworkfoundation.com/research/isociety/MobileUK_main.jsp [Accessed 1 July 2003].

Davies, M., 2002. A usability test by 3G Lab. Comparison oftwo camera phones: Nokia 7650 vs. Sony-Ericsson T68i[online]. 3G Lab Limited. Available from: http://www.3glab.com/products/usabilitysuite.html [Accessed 1July 2003].

de Angeli, A., Sutcliffe, A., and Hartmann, J., 2006.Interaction, usability and aesthetics: What influencesusers’ preferences? Proceedings of DIS 2006, 26–28 June.271–280.

Diefenbach, S. and Hassenzahl, M., 2009. The ‘BeautyDilemma’: Beauty is valued but discounted in productchoice. Proceedings of CHI 2009, 4–9 April, Boston, MA,1419–1426.

Han, S.H. and Hong, S.W., 2003. A systematic approach forcoupling user satisfaction with product design.Ergonomics, 46 (13/14), 1441–1461.

Han, S.H., et al., 2004. Identifying mobile phone designfeatures critical to user satisfaction. Human Factors andErgonomics in Manufacturing, 14 (1), 15–29.

Hassenzahl, M., 2004. The interplay of beauty, goodness andusability in interactive products. Human-ComputerInteraction, 19, 319–349.

Hassenzahl, M., Beu, A., and Burmester, M., 2001.Engineering Joy. IEEE Software, 18 (1), 70–76.

Huber, O., Wider, R., and Huber, O.W., 1997. Activeinformation search and complete informationpresentation in naturalistic risky decision tasks. ActaPsychologia, 95, 15–29.

International Organization for Standardization, 1994.DIS 9241–11, Ergonomics requirements for office workwith visual display terminals (VDTs): Part 11:Framework for describing usability in terms of user-based measures.

Isiklar, G. and Buyukozkan, G., 2007. Using a multi-criteriadecision making approach to evaluate mobile phonealternatives. Computer Standards and Interfaces, 29, 265–274.

Jordan, P.W., 1997. Usability evaluation in industry: gainingthe competitive advantage. In P. Seppala, T. Luopajarvi,C.H. Nygard, and M. Mattila, eds. From experience toinnovation – IEA 1997. Proceedings of the 13th triennialcongress of the International Ergonomics Association,Tampere, Finland, 29 June–4 July 1997, IEA Press.

Jordan, P.W., 1998. An introduction to usability. London:Taylor & Francis Ltd.

Jordan, P.W., 2000. Designing pleasurable products. London:Taylor & Francis.

Jordan, P.W., 2001. Usability and product design. In: W.Karwowski, ed. International encyclopaedia of ergonomicsand human factors, vol. II. London: Taylor & Francis,1426–1428.

Jordan, P.W., 2002. The personalities of products. In:W.S. Green and P.W. Jordan, eds. Pleasure withproducts: Beyond usability. London: Taylor & Francis,19–47.

Jordan, P.W. and Thomas, B., 1995. But how muchextra would you pay for it? An informal techniquefor setting priorities in requirements capture. In: S.A.Robertson, ed. Contemporary ergonomics:Proceedings of the annual conference of the ErgonomicsSociety, 4–6 April, Kent. London: Taylor & Francis,145–148.

Ergonomics 1527

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014

Page 16: The importance of usability in product choice: A mobile phone case study

Khalid, H.M., 2001. Can customer needs express affectivedesign? In: M.G. Helander, H.M. Khalid, and M.P.Tham, eds. Proceedings of the international conference onaffective human factors design, 27–29 June, Singapore.190–198.

Lightner, N.J., 2003. What users want in e-commerce design:effects of age, education and income. Ergonomics, 46 (1),153–168.

Lingaard, G. and Dudek, C., 2003. What is this evasive beastwe call user satisfaction? Interacting with Computers, 15,429–452.

Lohse, G.L., 2000. Usability and profits in the digitaleconomy. In: S. McDonald, ed. Proceedings ofHCI 2000. People and computers XIV – Usability orelse. London: Springer-Verlag, 3–15.

McClelland, I., 1995. Product assessment and user trials. In:J.R. Wilson and E.N. Corlett, eds. Evaluation of humanwork. A practical ergonomics methodology, 2nd edition.London: Taylor & Francis Ltd., 249–284.

McNamara, N. and Kirakowski, J., 2006. Functionality,usability and user experience: Three areas of concern.Interactions, November–December, 26–28.

Maguire, M., 2004. Does usability ¼ attractiveness? In: D.McDonagh, P. Hekkert, J. van Erp, and D. Gyi, eds.Design and emotion. London: Taylor & Francis Group,303–307.

Maguire, M.C., Butters, L.M., and McKnight, C., 1994.Usability issues for buyers and users of homeelectronic products In S.R. Oppermann, S. Bagnara,and D. Benyon, eds. Human Computer interaction: Fromindividuals to groups in work, leisure, and everyday life.Proceedings of ECCE 7, 7th European conference oncognitive ergonomics, Bonn, 5–8 September 1994. 117–133.

Miles, M.B. and Huberman, A.M., 1994. Qualitative dataanalysis: An expanded sourcebook, 2nd edition. ThousandOaks, CA: Sage Publications.

Norman, D.A., 1988. The psychology of everyday things.New York: Basic Books.

Overbeeke, C.J., et al., 2002. Beauty in usability: Forgetabout ease of use. In: W.S. Green and P.W. Jordan, eds.Pleasure with products: Beyond usability. London: Taylor& Francis, 9–17.

Preece, J., Rogers, Y., and Sharp, H., 2002. Interactiondesign: Beyond human computer interaction. Chichester,UK: John Wiley and Sons Inc.

Robson, C., 2002. Real world research, 2nd edition. Oxford:Blackwell Publishers.

Rohlin, K., 2002. Usability influences on customer productchoice. Norwegian University of Science and TechnologyWebsite. http://design.ntru.no.internt/p19_2002/PD9_Arikkel_1/file.asp?ID=90 [Accessed 28 August2003].

Seva, R.R., Duh, H.B.-L., and Helander, M.G., 2007. Themarketing implications of affective product design.Applied Ergonomics, 38, 723–731.

Sinclair, M.A., 1995. Subjective assessment. In: J.R. Wilsonand E.N. Corlett, eds. Evaluation of human work. Apractical ergonomics methodology, 2nd edition. London:Taylor & Francis Ltd., 69–100.

Stanton, N. and Baber, C., 1996. Factors affecting theselection of methods and techniques prior to conductinga usability evaluation. In: P.W. Jordan, B. Thomas, B.A.Weerdmeester, and I. McClelland, eds. Usabilityevaluation in industry. London: Taylor & Francis, 39–48.

Tractinsky, N., 1997. Aesthetics and apparent usability:empirically assessing cultural and methodologicalissues. In: S. Pemberton, ed. Human factors in computingsystems (CHI ’97), 22–27 March, Atlanta, Georgia.New York: ACM, 115–122.

1528 Z. Mack and S. Sharples

Dow

nloa

ded

by [

Uni

vers

ity o

f T

asm

ania

] at

02:

51 0

3 Se

ptem

ber

2014