Psychology Investigations A handy guide to module 2542 Nicola Santamaria January 2001

Research Aim Try to complete this statement:- “The aim of my research is to find out more about ….” Some suggested phrases include..  …why some people…  …whether some people…  …how people…  …if people…

Hypotheses When you have decided your research aim then you need to formulate two hypotheses:- The Null Hypothesis The Alternative Hypothesis The Null Hypothesis says ‘there will be no difference...’ The Alternative Hypothesis says ‘there will be a difference…’

Variables There are two important variables to consider:- The Independent Variable (IV) The Dependent Variable (DV) The IV is the one you manipulate The DV is the one you measure You also try to control as many extraneous variables as you can so that they do not interfere with the action of the IV on the DV.

Sample Decide who your target population are and how you will make a sample from them. Consider how to minimise the bias in your sample. Do not say you will take a random sample unless you are certain this is possible (it seldom is). Aim to have a sample which is representative of all the people in the target population.

Materials What equipment will you need to conduct your investigation? Examples might include: Pencil and paper A tally chart A stop-watch Questions to ask your participants

Data collection How will you collect your data? What are you measuring? (refer back to the DV) How accurately do you need to measure the DV? How many sets of data do you need from each participant? How many participants do you need to test or observe? What will you do with the data, once collected? (refer to next slide)

Data presentation How will you illustrate your results? Suggestions include:- Tables, such as frequency tables Graphs, such as bar charts and frequency polygons Pie charts Summary tables (see next slide)

Results summary How will you summarise the results? Suggestions include: Measures of central tendency (mean, median & mode) Measure of dispersion (standard deviation & range)

Results analysis Sometimes Inferential Statistical tests are required. These include Chi-squared test Mann-Whitney U Wilcoxon Sign test (Binomial) Spearmans (correlation)

Conclusion After an inferential test you must make a statement about the significance of your results. An example might be: “The results were significant at 5%, so we can reject the Null Hypothesis”. Or “Because the results were not significant at 5% we are unable to reject the Null Hypothesis”.

Ethical issues You should always consider whether your research is ethical, before you start. You will have to seek your teachers approval for your work before you start. Afterwards be prepared to consider improvements to make your research more ethical. Be aware of the limitations which ethical practice place on your investigation.

Reliability & Validity How reliable were your measures? Would another researcher have recorded the same data? Would you have got the same results another time? How valid were your measures? Were you really measuring what you set out to measure?

Alternative measures How else could you have measured the DV? Could your measurements have been more accurate? Could your measurements have been more reliable? Could your measurements have been more valid?

Overcoming weaknesses What are the weaknesses of your design? How could you overcome these weaknesses? Could the sample have been more representative? Could the measurement have been more accurate? Could your instructions have been more detailed?

Advantages and disadvantages List the advantages and disadvantages of each kind of design. The various designs include: Questionnaires Observations Experiments Correlation studies