QUANTITATIVE RESEARCH METHOD

4.2 Quantitative Research Methods

Uses deductive method of knowledge acquisition

Intends to falsifies an existing theory Tries to generate generalizable knowledge

Accepts objectivity of knowledge Uses a standard measurement instruments The researcher is independent in the process of

knowledge construction Quantifies the phenomena in terms of numbers Intends with prediction and controlling

Example - User involvement in system development Success

Participation

Conflict Conflict

resolution

Influence

Conceptual Framework of User Involvement

Type of quantitative research

The purposes of research can be categorized as:

Descriptive (fact finding) Explorative (looking for patterns) Analytical (explaining why or how) Predictive (forecasting the likelihood of

particular events)

Descriptive

It started during the Roman Empire Took census to know the number of people

under its empire Used for taxation purposes Seeks to accurately describe current or

past phenomena - to answer such questions as:a) What type of open source software

frequently used in Ethiopia?b) What type of computers mostly imported in

Ethiopiac) What are the main software tools used by

end users?

Explorative

Seeks to understand psychological and sociological phenomena in an effort to find behavioral patterns: a) How do users use the new software

system?b) Why would users use the software in this

way contrary to original purpose. For example use of Internet for news rather work related matters

c) What are the antecedent factors for software project success?

Analytical

Seeking to explain the reasons behind a particular occurrence by discovering causal relationships. Once causal relationships have been discovered, the search then shifts to factors that can be changed (variables) in order to influence the chain of causality. Typical questions are:

a) Do user involvement in software development and users IT skills increase software success?

b) Does Hardware performance have an influence on software failure?

Predictive

Seeks to forecast the likelihood of particular phenomena occurring in given circumstances. a) Does internet bandwidth predict growth online

business services ?b) Can the new software system increases the

organization’s efficiency?c) To what extent does new software predict

growth of the organization profit? This compares independent (IV) and

dependent variable (DV). We can predict DV by measuring IV

Experimental Research Design

Used to identify cause and effect relationship

Three types Pre-experimental design Quasi experimental True experimental

Pre-experimental design

A treatment is given for a group at different time and then it is investigated if the treatment brings the change or not

It is relatively weak design as compared the other two

ObserveObservati

on Apply

treatment

Quasi experimental

The sample are grouped into two groups Randomization is not considered Treatment is given for one group and the

group or controlled group will not receive the treatment

Measures undertaken on both group to check weather the treatment brings change or not

Quasi …

G1

G2 X

O

O

True experimental

The sample are randomly grouped into two Treatment is given one group and the

other group will not receive the treatment Measures will be taken to see the Impact

of the treatment group

True …

G1

G2 X

O

O

Ran

dom

izati

on

Method of Data Collection

Structured Interview questions for Face to face or Telephone

Questionnaire Online questionnaire (there are free sites) Computer simulation Computer log files – Data like

Attempts made by Hackers attempts made to break passwords

Face to face interview

Interviews are fairly structured The researcher asks standard set of

questions and nothing more Interview is formal and emotionally neutral The relationship terminated when the

interview is completed It has a distinct advantage of establishing

rapport with potential participants and gain cooperation Yields highest response rate But time and expense is unaffordable if

interviewees are found in different regions and population is large

Telephone Interview

Are less time consuming and less expensive

Can access all participants who has a telephone

Response rate is not as high as face to face interview

But higher than the mailed questionnaire Sample is biased as it ignores people

without telephone Both has the advantage to clarify

ambiguous answers and when appropriate, seek follow up information

Not feasible for large size of population

Guideline for Quantitative interview

Interview should be carefully planned and precisely worded to yield the required data

As you write the questions consider how you can quantify the response, and modify the questions accordingly

Consider asking questions that will elicit qualitative information as well

Restrict each question to a single idea Save controversial questions for the latter

part of the interview

Questionnaire Survey

Can be sent to large number of people, including those who live thousands of miles away

Researcher does not have contact with the respondents

Helps respondent to freely express their idea than they would be in personal interviews, especially on sensitive and controversial issue

Draw back of questionnaire

Majority of people don’t return Returned responses may not be a true

representative of the originally selected samples

Rely on self report

Questionnaires design

Questionnaires make use of lists and rating scales

Behaviors and attitudes are complex and cannot be easily evaluated and quantified

Check list is a list of behaviors, characteristics or other entities that a researcher is investigating

Either the researcher or participants simply check(s) items from the list

What are features of user friendly software1. Graphical interface2. Clear navigation direction3. Immediate feedback4. Other specify ____________

Questionnaire …

A rating scale is more useful when a behavior, attitude, or other phenomena of interest needs to be evaluated on a continuum scale

It is designed with the following scales 1. “inadequate” to “excellent”, 2. “never” to “always” or 3. “strongly disapprove” to “strongly

approve”

Guideline for Questionnaire

1. Keep it short• What do I do with the information?• Is it absolutely essential to have this

information to solve part of the research problem

2. Use simple, clear, unambiguous language3. Check for unwarranted assumptions implicit in

your questions How many cigarette do you smoke each day?

Good to add a choice 25 ___ 25-16 ____ 15-5 ___ <5 ____ None ____

4. Word your questions in ways that don’t give clues about preferred or more desirable responses

What strategies have you used to try to quit smoking?

Leads him to list strategies he did not try

Guide line …

Check consistency – that leads to give contradictory answer for two questions

Determine in advance how you will code the response

Keep the respondents task simple Provide clear instructions Make the questionnaire attractive and

professional looking Conduct a pilot test

Give for half a dozen friends to see they have difficulty understanding any items

Scrutinize the almost final product carefully to make sure it address your needs

Sampling

In descriptive study, the researcher wants to determine the nature of how things are

Describe one or more characteristics of a fairly large population – e.g 3 million

When population is large, select a subset or a sample of the population

Makes conclusion from the sample about the population

Sample must be true representative of the population Refers to the external validity of a research

study

Quantitative Data Analysis

Two types1. Descriptive statistics

Used to describe the phenomena with frequency, mean, median, mode

2. Inferential statistics• This statistics is used to infer about the

population from the sample data• T-test to compare means of two groups• Analysis of Variance (ANOVA)

• When groups more than two

Analysis

• Linear Regression (when the correlation follows the same pattern)

• Logistic Regression (when there is linear correlation)

Review Qeustions

1. How quantitative method differ form qualitative method

2. How do you design quantitative methods?

3. What is the final outcome of the quantitative research?

4. What are the main data collection instruments

5. How do you analyze quantitative research data?