Research methods

• What is an aim?

  A general statement of what the researcher intends to investigate
• What is a hypothesis?


  Statement that is made at the start of a study and states the relationship between variables that can be tested
• What is a directional hypothesis?

  Researcher makes clear the sort of difference that is anticipated between two conditions

  - Used when the findings of previous research suggest a particular outcome

  E.G. People who drink caffeine will be have a faster reaction time to the people who don't drink caffeine
• What is a non-directional hypothesis?

  simply states that there is a difference between conditions.

  - Used when there is no previous research or findings from earlier studies are contradictory

  E.G. There will be a difference in the reaction time between people who drink caffeine and people who don't
• What is an independent variable?


  variable that is manipulated
• What is a dependent variable?


  variable that is measured
• What is operationalisation?


  Clearly defining variables in terms of how they can be measured
• What is an extraneous variable?


  Any other variable that might potentially interfere with the IV or DV that should be controlled or removed
• What is a confouding variable?

  Factors other than the IV that may effect your results.
• What are demand characteristics?


  cues in an experiment that tell the participant what behaviour is expected. Leading the "please-U effect or the screw-U effect to occur"
• What is the investigator effect?

  Any unwanted influence of the investigator on the research outcome
• What is randomisation?


  The use of chance in order to control for the effects of bias when designing materials and deciding the order of conditions.
• What is standardisation?


  Using exactly the same formalised procedures and instructions for all participants in a research study.
• What is experimental design?

  The different ways in which the testing of participants can be organised in relation to the experimental conditions
• What is an independent groups design?

  Two separate groups of participants experience two different conditions of the experiment
• Evaluation of an independent groups design

  Strengths

  - Order effects aren't a problem so pp's are less likely to guess the aim (Demand Characteristics)

  Weakness'

  - Participants who occupy the groups are not the same, therefore participant variables may affect the results.

  - Problem dealt with random allocation
• What is a repeated measures design?


  All participants take part in all conditions
• Evaluation of Repeated Measures Design

  Strengths

  - Controlled participant variables

  - Fewer pp's needed

  Weakness'

  - Order effects can effect the result E.G. demand characteristics, fatigue etc Dealt through counterbalancing
• What is counterbalancing?


  An attempt to control for the effects of order in a repeated measures design: half the participants experience the conditions in one order, and the other half in the opposite order. (ABBA)
• What is a matched pairs design?

  Pairs of participants are first matched on some variable(s) that may affect the DV. Then one member of the pair is assigned to Condition A and the other to Condition B.
• Evaluation of Matched Pairs Design

  Strengths

  - Reduces order effects so demand characteristics are less of a problem

  Weakness'

  - Participants can never be matched exactly

  - Matching can be time consuming and expensive especially of a pre test is required.
• What is a lab experiment?

  They are experiments conducted in highly controlled environments.
• Evaluation of a Lab experiment

  Strengths

  - High control over extraneous variables

  - High internal validity

  - Replication is more possible

  
  

  Limitations

  - May lack generalisability

  - Low external validity

  - High chance of demand characteristics

  - Low mundane realism
• What is a field experiment?

  An experiment that takes place in a natural setting within which the researcher manipulates the IV and records the effect on the DV
• Evaluation of field experiments

  Strengths

  - Higher mundane realism

  - High external validity

  
  

  Limitations

  - Low internal validity to lack of control of extraneous variables.
• What is a natural experiment?

  Experiment where the change in IV isn't brought by the researcher and researcher records the effect it has on the DV
• Evaluation of a natural experiment

  Strengths

  - Provide opportunities that may have otherwise not have been done for practical or ethical reasons

  - High external validity

  
  

  Limitations

  - Change in IV occurs rarely so limits generalisations

  - Participants aren't randomly allocated to conditions
• What is a quasi-experimental design?


  IV based on an existing difference between people e.g. age, gender.
• Evaluation of a quasi - experimental design?

  Strengths

  - Often carried out under controlled conditions thus sharing the strengths of a lab experiment

  
  

  Limitations

  - Cannot randomly allocate participants to conditions so there may be confounding variables
• What is the target population?


  Group of individuals that a researcher is interested in studying
• What is a sample?


  Group of people selected from the target population to take part in the study
• What is a sampling technique?

  Method used used to select the sample from the target population
• What is a random sample?

  All members of the target population have an equal chance of being selected

  - list of members of the target population is obtained

  - Members assigned a number

  - sample is generated through a lottery method ( hat or computer based randomiser)
• Evaluation of random sampling

  Strengths

  - Free from researcher bias

  
  

  Limitations

  - Time consuming to conduct

  - There's still a chance you can end up with an unrepresentative sample

  - Selected pp's may refuse to take part so you end up with a sort of volunteer sample
• What is systematic sampling?

  Every nth member of the target population is selected
• Evaluation of systematic sampling

  Strengths

  - avoids researcher bias

  
  

  Limitations

  - Selected pp's may refuse to take part so you end up with a sort of volunteer sample
• What is stratified sampling?


  Dividing the population into strata then selecting a sample from each of these groups, reflects the proportions of people in the target population in the sample
• Evaluation of stratified sampling

  Strengths

  - avoids researcher bias

  - ensures a representative sample

  
  

  Limitations

  - Selected pp's may refuse to take part so you end up with a sort of volunteer sample
• What is opportunity sampling?


  Researchers may simply decide to select anyone who happens to be willing and available
• Evaluation of opportunity sampling

  Strengths

  - convenient

  - saves time and money

  
  

  Limitations

  - Unrepresentative

  - Researcher bias

  - Selected pp's may refuse to take part so you end up with a sort of volunteer sample