methods: experimental variables

Question 1

what are extraneous variables in an experiment?

Answer 1

• factors that may have an unwanted effect on the dependent variable
• they can potentially influence the DV but are not the focus of the experiment

Question 2

what is a confounding variable?

Answer 2

• an extraneous variable that influences the DV
• makes it look like the effect is caused by the IV, when it could be due to the confounding variable
• confounds the results, making it unclear whether the effect is from the IV

Question 3

why is it important to control for extraneous variables in an experiment?

Answer 3

• to ensure that the effect measured is truly caused by the IV
• to avoid confounding the results with other variables

Question 4

how can the extraneous and confounding variables by divided?

Answer 4

• extraneous and confounding variables can be divided into two types: situational variables and participant variables

Question 5

what are situational variables in an experiment?

Answer 5

• extraneous variables that affect the environment in which the study is conducted
• include factors such as lighting, noise, temperature, disturbances, and time of day

Question 6

how can situational variables affect the results of a study?

Answer 6

• they can influence the outcome of the experiment, making it seem as though the independent variable had an effect when it was actually due to the situational variable

Question 7

how can situational variables be controlled in a study?

Answer 7

• by holding the variable constant for all ppts
• this ensures the variable affects everyone equally

Question 8

how can situational variables be eliminated in a study?

Answer 8

• by removing the possibility of the variable affecting the study in the first place
• ensuring that the extraneous variable doesn’t occur during the experiment

Question 9

what are participant variables in an experiment?

Answer 9

• characteristics of ppts that could affect results of study
• include factors eg motivation, personality, intelligence, experience, age, and skills

Question 10

how can participant variables affect the results of a study?

Answer 10

• can influence the dv, leading to changes that are not due to the iv

Question 11

how can participant variables be controlled in an experiment?

Answer 11

• some ppt variables, like age and gender, are easier to control
• more complex variables, like motivation and experience, may require more thoughtful control measures

Question 12

is it necessary to control all situational and participant variables in an experiment?

Answer 12

• no, it would be time-consuming and unnecessary
• only variables that could have an unwanted impact on the dv need to be controlled

Question 13

when is it necessary to control situational variables like room temperature?

Answer 13

• only when variable could impact performance or results of exp
• eg, if testing memory and temperature affects concentration, it should be controlled

Question 14

what are experimenter or researcher effects?

Answer 14

• way an experimenter may influence the outcome of exp
• can be due to actions or mere presence of the researcher
• may include subtle cues that influence how ppts respond

Question 15

what is an example of an obvious experimenter effect?

Answer 15

• a female researcher asking a male ppt about his attitudes towards gender equality
• a young researcher asking an older ppt about youth culture

Question 16

what is the Hawthorne Effect?

Answer 16

• phenomenon where the mere presence of researcher affects ppts’ performance
• named after a study where workers’ productivity increased simply because they were being observed

Question 17

what are demand characteristics?

Answer 17

• when the experimenter’s influence causes ppts to change their behaviour
• ppts may alter behaviour to meet the experimenter’s expectations

Question 18

what did Rosenthal’s expectancy effect research demonstrate?

Answer 18

• psychology graduates were told one set of rats was “brighter”
• the “bright” rats learned faster than the “dull” rats, despite no real difference

Question 19

what was Rosenthal’s conclusion from his research on expectancy effects?

Answer 19

• students may treat subjects differently based on their expectations
• this can lead to unintended actions, like altering the timing or reporting false results

Question 20

how can experimenter effects explain failures to replicate results?

Answer 20

• experimenter effects can lead to unintentional biases
• this may cause researcher to find results that others fail to replicate