research methods: bias in experiments

Question 1

what is experimenter effects?

Answer 1

• the way an experimenter may influence outcome of experiment by their actions or presence
• means that behaviour of experimenter may affect ppt and thus affect dv
• need to be controlled
• experimenter effects come from cues or signals from experimenter that may affect the ppts response
• cues might be the tone of the voice or non-verbal cues

Question 2

what is the Hawthorne effect?

Answer 2

• the presence of the researcher affects performance on a task

Question 3

what are demand characteristics?

Answer 3

• when the effect of the experimenter causes the ppt to alter behaviour to meet the expectations (whether real or imagined) of experimenter.
• ppt is not a passive responder but is actively engaged in trying to work out what is going on and how they should perform

Question 4

why may demand characteristics occur?

Answer 4

• because we are active, thinking human beings
• due to actual conversation during experiment e.g. instructions or any non-verbal communication (experimenter nodding)
• due to what ppt may have already have heard about experiment (e.g. from other ppts)

Question 5

what are the two ways to reduce the effect experimenter may have?

Answer 5

• double-blind technique
• single-blind technique

Question 6

what is the double-blind technique?

Answer 6

• ppts are not aware of which groups they are in and what study is about
• study is also carried out by someone other than person who knows who is doing what
• neither the ppts not person running study knows precisely what is expected

Question 7

what is the single-blind technique?

Answer 7

• ppts not aware of what is expected but person carrying out study is
• stops ppts expectations from affecting results but does not stop experimenter effects

Question 8

what are control issues?

Answer 8

• in experiments using human ppts, many variables can influence outcomes
• important to identify these variables and then put into place controls to **help prevent them having any effect of experiment*(
• various control techniques have been established to deal with control issues

Question 9

what is standardisation?

Answer 9

• making an experiment the same experience for all ppts

Question 10

what are standardised instructions?

Answer 10

• set of instructions given to all ppts that can be used to eliminate experimenter effects because it removed potential for experimenter to give verbal or non-verbal cues to ppts

Question 11

what are standardised procedures?

Answer 11

• stages of experiment, timings, apparatus, etc
• ensures that all ppts are treated same way (other than change in conditions to iv)
• there is no variation in the way they experience research that may affect the way they behave
• standardisation is important as it improved replicability of experiment