RESEARCH METHODS 2

Psychological research methods

•The type of data collected in psychological research is used as the basis of classifying research methods into two broad categories:

▫Qualitative research▫Quantitative research

Qualitative research

•Involves the collection of qualitative data▫Non-numerical data (not expressed in

numbers)▫Descriptions, comments etc.

•For example:▫May be a researcher’s description of how a

participant reacted, a participant’s comments on how they felt, video recordings of social interaction within a group, diary records, photographs etc.

Qualitative research

•This type of data can describe any aspect of a person’s thoughts, feelings or behaviour.

•May be collected as a verbal or written statement or as a description of behaviour observed and recorded

Quantitative research

•Involves the collection of quantitative data▫Numerical data▫Usually obtained using scales or tests▫Usually obtained in experimental or

correlational research

But! Research can include both!•Experiments can produce qualitative and

quantitative data •E.g. Zimbardo (1972) experiment:

▫Observed, described and reported common and unusual behaviour and verbal responses, often referring to specific examples

▫Extent to which prisoners were prepared to obey demands in graph and table form

The method to choose depends on what the researcher is trying to find out

Qualitative data Quantitative data

Researchers are able to interact with participants and obtain rich and detailed data

But, personal bias and open-endedness of questions can be hard to control

Data collection under conditions that are strictly controlled to prevent or minimise other factors

But, may not be able to obtain accurate or detailed information

•Learning Activity 7.1 Question 3

•Learning Activity 7.2 Media Response ▫(using body image articles)

Experimental research

•An experiment is used to find out whether one variable (the IV) causes a change in another variable (the DV)

•Deliberate manipulation of IV▫Typically involves exposing some

participants to the IV and not exposing others to the IV.

•Always designed to test a hypothesis

Operationalising the IV and DV•Operational hypothesis:

▫Is a research hypothesis that refers to how the variables being studied will be observed and measured.

•Activity: Copy the following example in the middle of your page▫‘Year 11 VCE students who continuously listen

to loud rock music when solving previously unseen written problems will solve fewer problems during a one-hour session than Year 11 VCE students who do not listen to rock music’

•Label the key characteristics of the operational hypothesis and colour code the evidence

•Key characteristics:▫IV is described in operational terms▫DV is described in operational terms▫The population from which the sample in

drawn is stated▫How the experiment will be conducted is

stated

•This hypothesis has all the required characteristics:▫IV is described in operational terms:

continuously listening to rock music throughout one hour session

▫DV is described in operational terms: the number of previously unseen written problems that are solved

▫The population from which the sample in drawn is stated: Year 11 VCE students

▫How the experiment will be conducted is stated: one group will listen to loud rock music when problem-solving (experimental group) and another will not listen to loud rock music when problem-solving (control group).

Extraneous variables• Variable other than IV that can cause a change in

DV

• Participant variables▫ Individual characteristics of participants

(intelligence, sex)• Situational variable

▫ Any variable associated with the experimental situation (background noise, time of day)

• Experimenter variable▫ Variables associated with the personality

characteristics of the experimenter or their behaviour (their expectations, how they dress and attractiveness)

Confounding variables

•Variable other than the IV that has had an unwanted affect on the DV, making it impossible to determine which of the variables has produced changes in the DV.

•Effects are confounded or ‘confused’ with those of IV

Correlational studies•Non-experiment research method used to

investigate the relationship between two or more variables

•E.g. The relationship between air temp and violent crimes, level of anxiety and health problems

•Correlation: how two variables are ‘co-related’

Correlation

•Positive: two variables change in same direction (increase/increase)

•Negative: two variables vary or move in opposite directions (increase/decrease or decrease/increase)

Correlation co-efficient

•Can range form +1.00 to -1.00•Plus or minus = positive or neg

correlation

•Number describes strength of correlation or relationship ▫Closer to +1.00 or -1.00, the stronger the

relationship

•Scatter plots: see pg. 303-4

Descriptive statistics •Frequency distribution

▫Normal distribution ▫Positively and negatively skewed

distributions▫Bimodal distribution

•Measures of central tendency▫Mean▫Median▫Mode

Descriptive statistics •Variability

▫Range▫Variance▫Standard deviation

•Reliability and validity in research▫Reliability: the consistency, dependability and

stability of the results obtained from a research study

▫Validity: the research study has produced results that accurately measure the behaviour or event that is claims to have measured

Statistical significance and p values

•Statistical significance: used to indicate how likely it is that any result obtained from a research study is due to chance (e.g. group composition, participant characteristics etc)

•The level of significance of any given result is called a p value.

• It is generally accepted that the likelihood or probability that the result might be due to chance is 5 or fewer times (≤5) in 100

Statistical significance and p values

•That is, the result is significant at the 0.05 level; that is p≤0.05. A significance level of p≤0.06 would indicate there was a 6% chance that the result obtained was most likely due to chance and this would generally be viewed as unacceptable.

•The results are not significant and, therefore, do not support the research hypothesis.

Homework:

•Complete:▫True/ False quiz pg. 321▫Chapter test pg. 322