Research Methods Flashcards
What is an aim?
It’s a general statement which describes what a psychologist intends
to investigate.it states the purpose of the study.
What are examples of an aim?
- to see whether a person’s confidence level has an effect on the likelihood of them obeying.
- to find out if a collector’s appearance would affect the donations to charity
- to investigate the effect of group size on conformity
What is a hypothesis?
It’s a clear, precise, testable statement that states the relationship between the variables to be investigated. It predicts what the results of a piece of research will be.
What is a Directional Hypothesis (one tailed)?
States the direction of the predicted difference between the two groups. Predicts the direction in which the results are expected to go.
Example. people who eat fish will score significantly more on an
intelligence test than those who do not eat fish.
What is a Non-Directional Hypothesis (two tailed)?
It predicts simply that there is a difference between two conditions or two groups of participants, without stating the direction of difference.
Example There will be a difference in scores on an intelligence test
between people who eat fish and those who do not.
What is a variable?
A variable is anything that can vary or change within an investigation.
They are generally used in experiments to determine if changes in
one thing result in changes in another.
What is an Independent Variable (IV)?
Is the variable which the researcher/experimenter manipulates to see what effect it has on the dependent variable.
An IV has two conditions- experimental condition and the control condition.
What is a Dependent Variable (DV)?
Is the variable which is affected by the changes in the independent variable and is what is measured by the researcher/experimenter.
What are Operationalising Variables?
Operationalisation refers to the process of making variables physically measurable or testable.
This is done to make the hypothesis clear, testable, objective and replicable.
This can be done by recording some aspect of observable behaviour
that is assumed to be indicative of that variable.
What is an Alternative/Research Hypotheses
It predicts that there will be significant difference or relationship between two conditions you are investigating.
What is an Experimental Hypothesis?
A hypothesis used only in experiments which predicts the changes in the IV will cause an effect on the DV.
Example :There will be a significant difference in the number of words recalled by 16-19 year old students from a list on a Monday morning than on a Friday afternoon.
It predicts differences and not relationships between groups.
What is a Correctional Hypothesis?
- Used in correlational research
- It predicts there will be a relationship or association between two variables.
Example: There will be a relationship between the amount of studying a student does and their mark in the exam.
What is a Null Hypothesis?
States that results are due to chance and are not significant in terms of supporting the idea being investigated.
Remember it predicts that nothing is going on, there is no difference or relationship between variables you are investigating and any link which your results show is just a ‘blip’ due to chance.
What is an Experimental Design?
The way participants are distributed between different conditions in an experiment
What is an ‘Independent Group’?
- Involves using different participants in each condition of the experiment.
- The performance of the two groups is then compared.
- This is usually random
Example: To study the effect of noise on performance in a memory test- one group are given a memory test in no noise condition and the other group is given the same memory test in a noise condition
What are ‘Repeated Measures’?
- Involves using the same participants in each condition of
the experiment - The two sets of data from each condition would then be
compared.
What are ‘Matched Pairs’?
- Involves using different but similar participants in each condition of the experiment
- Participants are matched on some variable that may affect the DV other than the IV e.g. age, sex, intelligence, ability
- Then one member of the pair is assigned to condition A and one to condition B.
- The performance of the two groups would then be compared.
- E.g. Twins
What is an Advantage of Independent Groups?
- different participants so they aren’t similar, results are diverse
What is a Disadvantage of Independent Groups?
- time consuming
- less economic (expensive)
What is an Advantage of Repeated Measures?
- more controlled + compare results
- fewer people, less expensive
What is a Disadvantage of Repeated Measures?
- participants might not come back
- participants weren’t chosen at random, researcher bias
- they might change their behaviour
- angry, agitated, tired
What is an Advantage of Matched Pairs?
- order effect isn’t a problem
- no demand characteristics
What is a Disadvantage of Matched Pairs?
- hard to find similar participants
- time consuming
- they might not be the same
What is attrition?
When participants drop out of the study – more
problematic when same participants in both conditions
since you lose data for both conditions as well as
matched pairs as pairing is difficult.
When PPs drop out of a study (attrition) data are lost so fewer data = less powerful study. This can be a problem with matched PPs (and repeated measures if there is a gap between conditions)
Loss of a PP in these designs means losing their data from both conditions