Research Issues

Question 1

Extraneous variables

Answer 1

Any other variable that might potentially interfere with the IV (or DV). These additional, unwanted variables are called extraneous variables. Should be identified at the start of the study, researcher minimises them.

Many extraneous variables are straightforward to control like the age of participants or lighting in lab. These are described as ‘nuisance variables’. They don’t confound the results of the study.

Question 2

Confounding variables

Answer 2

DO change systematically with the IV. For example our energy drink group may be exited because they just saw Ronaldo. Therefore we have a second unintended IV-being exited or not.

Question 3

Demand characteristics

Answer 3

Participants are not passive within experiments and are likely to be spending much of their time trying to make sense of the new situation. As such, participant reactivity is a significant extraneous variable which is difficult to control.

In the research situation, participants will try to work out what is going on. Certain clues may help them interpret what is going on. These clues (or cues) are the demand characteristics of the experimental situation. Participants may also look for clues telling them how they should behave. Not natural behaviour-extraneous variable.

Question 4

Investigator effects

Answer 4

Unwanted influence of the investigator on the research outcome. For example smiling more at the people who drank energy drinks because we expect them to talk more. Also relates to actions of researcher in study of design.

Question 5

Randomisation

Answer 5

Minimises effects of extraneous/confounding variables. Use of chance methods to reduce the researchers unconscious biases when designing an investigation. Attempt to control investigator effects.

For example a memory experiment may involve participants recalling words from a list. The order of the list should be randomly generated so that the position of each word is not decided by the researcher.

Question 6

Standardisation

Answer 6

As far as possible, all participants should be subject to the same environment, information and experience. To ensure this all procedures are standardised, in other words there is a list of exactly what will be done in the study. This includes standardised instructions that are read to each participant. Such standardisation means that non-standardised changes in procedure do not act as extraneous variables.