PSYA4 Research Methods

Working Booklet

Topics include:

The Application of Scientific Methodology in Psychology

Designing psychological investigations Data analysis and reporting investigations

Name:

The Specification

The application of scientific

methodology in Psychology

The application of scientific methodology in Psychology

The Nature of Science:

Some of the first work done on the functioning of the human mind used introspection, a method involving the researcher sitting down and having a think about what they felt and thought about what was going on in their head. Thankfully psychology has moved on a lot since then and has now adopted the scientific method.

The scientific method requires theories to be objectively tested. The requirement for objectivity is based on the philosophical doctrine of empiricism. In order to be seen as objective, research must be rational and conducted and presented in such a way as to make it replicable.

Define the underlined terms above in your own words in order to make them clear to someone who knows nothing about science or psychology:

Empiricism

Rational

Replicable

Objectivity

Science or Non-Science?

Science is defined as being objective, replicable and rational. Often items are reported in the news as science but they lack the key features of scientific knowledge. Bordens and Abbott (2008) suggested that there are three ways of explaining human behaviour that we need to be careful not to confuse with scientific explanations.

Complete this table with a definition of each concept, an explanation of why it is not scientific and an example of something that is often explained in this way.

Common senseDescription:

Not scientific because:

Example:

Belief-basedDescription:

Not scientific because:

Example:

PseudoscienceDescription:

Not scientific because:

Example:

The scientific process:

Define the following key terms:

Complete the scientific process diagram:

Karl Popper (1935) believed that a deductive method was the best one to take because this involves proposing a theory and then seeking evidence to either support or contradict the theory. Popper argued that this allows researchers to seek falsification which will allow them to show that the theory has been tested properly. In short, researchers should actively search for ways to disprove their theory – if it is easy to disprove then the theory is altered and retested. If the theory is difficult to disprove…it’s a good theory!

Sir Karl Popper (1902-1994)

Induction:

Deduction:

Popper’s hypothetico-deductive method puts forward an idealized view of what he believed the scientific process should look like. Read about him on P508 and fill in the diagram below.

Kuhn (1996) criticized Popper for possessing such an idealized view of science and argued – that in the real world – science progresses rather differently. Kuhn argued that even when a theory is falsified, science still

clings to it. This is known as a paradigm. Only when enough refutable evidence or alternative theories have been put forward will this change – resulting in a paradigm shift and the moving forward of science.

A Paradigm Shift?

Outline the assumptions of the behaviourist and psychodynamic approaches to psychology:

Would you describe the approaches as having similar or different assumptions?

Do the two approaches represent one paradigm or two? Justify your conclusion.

Validating New Knowledge

Do a quick internet search and list 3 journals of Psychology

In your own words, describe what is meant by the term ‘peer review’:

Define the term ‘paradigm’:

What is a ‘paradigm shift?’

Why do you think the peer review system is important?

Evaluating Peer Review

Define or explain the following disadvantages of peer review. Don’t forget your PEAs! (Point, Explain, Apply)

Consistency with previous knowledge

Values in science

Bias in peer review

File drawer phenomenon

End of section assessment questions:

1. What is science? (2 marks)

2. Outline the scientific process (hypothetico-deductive method) (4 marks)

3. Explain the principle of falsifiability (2 marks)

4. Outline Kuhn’s description of paradigms (2 marks)

5. List 2 criticisms of the scientific approach (4 marks)

6. Choose two psychological approaches and explain, with examples, why they are scientific (3+3 marks)

7. Why may the scientific nature of research be reduced because it is being carried out on human beings? (4 marks)

8. What is meant by the term peer review (3 marks)

Designing Psychological Investigations

Designing Psychological Investigations

Selecting and Applying Research Methods:

Experiments try to establish cause and effect relationships. There are three main types - lab, field and natural (or quasi) experiments. The best experiments are ones which manipulate the IV and measure the effect this has on the DV. A causal relationship can only be established if all other extraneous variables are controlled. For this reason, the majority of experiments are conducted in lab environments.

Complete the below table to identify a definition, strengths and weaknesses of each experimental method:

Definition Strengths WeaknessesLab Experiment:

Field Experiment:

Natural Experiment:

Experimental Design

Once the researcher has chosen the experimental method which best suits the nature of the study, they then have to choose what type of design it will have. The choices are repeated measures, independent groups and matched pairs.

Task: Cut out paper men to identify repeated measures, independent groups and matched pairs design!

Now fill in the table below:

Experimental Strengths Weaknesses

Design:Repeated measures:The same PPs are used in both conditions.

Independent Groups:PPs are randomly allocated to different groups which represent the different conditions.

Matched Pairs:Pairs of PPs are closely matched and are then randomly allocated to one of the experimental conditions.

Observational Methods

Correlations are designed to investigate the strength of a relationship between two variables. The strength of this correlation is expressed by the correlation coefficient. The correlation coefficient is always between +1 and -1 where +1 represents a perfect positive correlation and -1 represents a perfect negative correlation. A correlation coefficient of 0 means that there is no correlation between the two variables.

There are two main types of observation - controlled and naturalistic. Controlled observations allow the experimenter to control any variables which may influence behaviour (e.g. noise). Naturalistic observations do not control any variables as they are purely observational. Observations can also be participant or non-participant based. Read about these on P516 now.

Task: identify which observational method is being evaluated below.

The advantage of this method is that it is high in ecological validity but has little control over confounding variables (variables which get confused with the IV).

Answer: _____________________

There is more control over confounding variables but this lowers ecological validity. The observed behaviour may not be a true reflection of what occurs and may be down to demand characteristics.

Answer: _____________________Notes on this type of observation are usually done retrospectively, affecting the reliability of results. It is however, easier to understand the context of the situation and therefore the behaviour which is occurring.

Answer: _____________________

Observations can be made as they occur, improving the reliability of the observation. However, the context of the situation may be ignored which does not give the researcher a true insight into the behaviour.

Answer: _____________________

Additional Methods

In addition to experimental, correlational and observational research methods, a psychologist may choose to use one of the following:

Surveys Interviews Case Study

Task: Read about them on P517 now and fill in the arrows below.

Which Research Method do I use?

Task: complete the chart using P518 of your textbooks.

Reliability, Validity and Sampling

Once a research method has been chosen the researcher needs to consider how useful the data is going to be. The main considerations are whether it will be reliable, valid and free from any sampling biases.

Quick Recap from AS:

Careful, this bit is new. Reliability can also be broken down into Internal and External.

Internal Reliability: The consistency of a measure within a test (i.e. all items need to be measuring the same thing).

External Reliability: The ability to replicate the results of a study and get the same or highly similar results.

Validity: the study measures what it is meant to measure.

Two types – Internal and External.

Internal Validity: The controlling of ALL variables, except the one being deliberately manipulated by the researcher.

External Validity: The extent to which the findings of the study can be generalised to others.

Reliability: If repeated, the same or highly similar results will be found.

Assessing and Improving Reliability and Validity:

Assessing Reliability: Assessing Validity:Internal: Assessed using the split-half method. This is when one half of the test is compared with the other in order to check whether the scores are consistent.

Internal: Running a pilot study allows researcher to identify whether there are any issues with the study (e.g. confusing items on the questionnaire). The researcher would also operationalise all variables.

External: Assessed using the test-retest method. The test is carried out on the same of similar PPs several times and the similarity of results is recorded. Alternatively, a correlation coefficient can be worked out between two sets of scores. The higher the correlation coefficient, the higher the reliability!

External: The researcher could test the findings from one study in a number of different settings and with different PPs. This would allow the researcher to see whether or not their results can be applied to the entire population or to what extent they are limited.

Improving Reliability:

Read page 520-21 and make a note of the four ways in which reliability can be improved.

Sampling

1)

2)

3)

4)

You’ll recall from your AS studies that there are three main types of sampling technique which an experimenter can choose from. These are:

Random samplingo Every member of the target population has an equal chance of

being selected, e.g. selected by computer from the electoral roll.

Opportunity samplingo Use whoever is immediately available e.g. go out and accost

passers-by.

Volunteer samplingo Use whoever puts themselves forward e.g. advertise in the

paper.

What are some of the issues that researchers face when looking to choose an appropriate sample? (e.g. generalising, bias etc - P524)

Ethical Issues

Why are ethical guidelines important to follow when conducting psychological research?

The main six ethical issues put forward by the BPS are:

Researchers should also consider following the following three (if applicable):

End of section assessment questions:

1. Name the three types of experiments and give an advantage and a disadvantage for each one (6 marks).

2. What are the three types of experimental design? (3 marks).

3. Explain two advantages of using observational methods in psychological research. (4 marks).

4. Why would researchers decide to use a case study rather than an interview to gather data? (4 marks).

5. What is the difference between internal and external reliability? (2 marks).

6. How can internal and external reliability be improved? (4 marks).

7. What is the difference between opportunity and random sampling? (2 marks).

8. Explain why it is important for researchers to control for any ethical issues that might arise. (6 marks).

Data Analysis and Reporting on Investigations

Summarising Quantitative Data (in graphical form)

Graphs are a useful way of summarising data which enable psychologists to easily see trends or patterns in data.

Three graphs which are commonly used to display quantitative data are:

Histograms

Bar Charts

Notes:

This graph is likely to be used when:

Scattergrams

Task: Fill in the gaps below!

1) The bars on a ____________ are joined together and are all of an identical ______________.

2) A histogram is commonly used to show __________ (e.g. IQ or test)

3) Bar charts are a useful way of showing ___________ statistics (e.g. percentages or ratios)

4) Bars on a bar chart are not ___________ together because the scale is not _______________.

5) Scattergrams are used to show the ____________ and _____________ of correlations.

Notes:

This graph is likely to be used when:

Notes:

This graph is likely to be used when:

6) Correlations can either be ______________, negative or have no correlation.

Probability and Significance:

Probability, or p, is expressed as a number between 0 and 1. 0 means an event will not happen, 1 means that an event will definitely happen. The P value will always be found to be between 0 and 1 due to the way in which it is calculated. To calculate the probability that a particular outcome will occur, it has to be divided by the number of possible outcomes.

One way to work out the probability of something occurring is to use this formula:

Probability = number of particular outcomes

number of possible outcomes

Sometimes it is a little more complicated to work out the probability of something. For example, there may be a probability that one in nine of the entire population will develop cancer at some point in our lives. However, the probability of us doing so is greatly increased by other factors such as lifestyle choices (e.g. diet and smoking). In this case, the researcher would need to break down the sample into groups according to these other factors. This enables the psychologist to work out conditional probability – the probability of something happening if something else occurs.

Define the term Probability:

……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………...

Probability and Significance continued….

Researchers use statistical tests to work out how probable it is that something might occur. For example, research has found a link between aggression and playing video games in children but we cannot accurately say that there is a high probability of this occurring across all children in the country without running a statistical test.

Research studies should have an experimental hypothesis and a null hypothesis which are being tested. Carrying out a statistical test allows us to either accept or reject these hypotheses (depending on the result).

Experimental hypotheses can either be:

D____________, or

N________________

A significant result is one where there is a low probability that chance factors were responsible for any observed difference, correlation or association in the variables tested.

The question is how large an effect (difference or relationship) is required for psychologists to conclude that a result is significant (i.e. not due to chance)? Psychologists have concluded that for most purposes, the 5% level of significance will be used (p=0.05)

Why O.O5?

………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

Which errors would a researcher be making if their significance level was:

a) Too lenient?b) Too strict?

Choosing a Statistical Test:

Statistical tests are used to calculate the probability that the results of a study are due to chance. The lower the probability, the more significant the result.

Before you can pick a statistical test you need to rank the data – i.e. allocating a number to each score. Data is usually ranked from the lowest to the highest. For example if there are 10 scores, the lowest score would receive a rank of 1, the highest a rank of 10. There will be the same number of ranks as scores…otherwise you’ve counted wrongly!

Task: Rank the participant scores in the below table.

Once you have ranked your data, follow these three steps to identify which statistical test is best to use.

1) Which level of measurement is the data? (nominal, interval, ordinal/ration)

2) What is the experimental design? (repeated measures, independent groups or matched pairs)

3) Am I looking for differences or relationships in the data?

The below diagram shows a simple way of selecting the right test:

Nominal Data? Chi-square (X²)

No

Participant Number:

Score: Rank:

1 122 193 44 165 176 137 158 119 1010 18

Task: Now fill in the gaps to identify your knowledge!

Spearman’s Rho is used when:

Testing for a c_________. The data is ordinal,

interval or ratio There are no or very few

tied ranks

Mann-Whitney is used when:

Testing for a difference There is an independent

groups design The data is _______,

________ or ________.Wilcoxon is used when:

Testing for a difference There is a r___________

m__________ design. The data is ordinal,

interval or ratio.

Chi-Squared is used when:

The data is N_________. No other test would be

suitable!

Correlation?

Independent Groups?

Spearman’s Rho

Mann-Whitney

Wilcoxon (T-test)

No

No

Using the Critical Values table:

After following the correct path and running your chosen statistical test you will be left with a number which tells you whether your data is significant or not.

The only problem is that you don’t know if the number is significant until you’ve compared it to a table of critical values. In essence, these critical values tell you whether or not you can accept your hypothesis. If your result fits into the P<0.05 level of significance shown on column…you can accept your hypothesis. If not…reject!

Using the Wilcoxon critical values table on P568 of your textbooks and the following results, work out whether the hypotheses for scenarios a-d can be accepted or rejected.

a) Participants will perform better in a memory test in the

afternoon than in the morning. Participants: 29 students.

Observed value: 153 (participants scored higher in the afternoon).

b) There will be a difference between a participant’s ability to

recite a poem before and after they have had a nap.

Participants: 14 children. Observed value: 20 (Participants scored

higher after a nap)

c) Participants will be more willing to help a stranger after

receiving first aid training. Participants: 26 teachers. Observed

value: 117 (Participants showed more helping behaviour after

training).

d) Participants will achieve a different score on a self esteem test

after eating a packet of Hob Nobs. Participants: 9 women.

Observed value: 4 (Participant’s self esteem was lower).

Analysing and Interpreting Qualitative Data:

Due to its richness, qualitative data cannot be analysed using statistical means. There are two stages in which qualitative data is analysed:

1) Organise the data.

2) Analyse the data through the use of the most appropriate mean.

For example, qualitative data is often gathered through the process of an interview. The researcher would have to transcribe the data (organise) and then analyse it using content analysis.

There are three main types of content analysis. Outline these in the post-it notes below:

The main problem with any form of content analysis is that it can be interpreted differently by different researchers. Taking the original data out of context may lead to it being misinterpreted or a different slant being taken. The only way to control for this is through the use of an external party who analyse, interpret and justify every decision they make during the process.

Reporting Psychological Investigations:

The reporting of psychological investigations is done in a way which ensures that it is both professional and well communicated. Using P455-6, identify the main elements of each section shown in the diagram below.

Interpretive Phenomenological Analysis:

Grounded Theory:

Discourse Analysis:

Title

Abstract

Intro

Method

Results

Discussion

References

Appendices

End of section assessment questions:

1) Outline the three main ways of representing quantitative data graphically.

2) What does the term probability mean?

3) In terms of probability, what is a significant result?

4) Identify the three steps a researcher will need to follow in order to decide which statistical test is best to use.

5) Spearman’s Rho is used when testing for a _________________ whereas Mann-Whitney is used when testing for a __________________.

6) What is a critical values table?

7) How is qualitative data analysed and interpreted?

8) Name the 8 sections found in the report of a psychological investigation.

Section C – Practice Exam Questions:

January 2010 Exam Paper:

June 2010 Exam Paper: