experimental design and internal validity

Question 1

A strength of independent groups:order effects are completely controlled

Answer 1

E:participants in this group only take part in one condition meaning they never repeat experimental tasks.this helps strengthen internal validity

Question 1

a limitation or independent groups:vulnerability to participant extraneous variables

Answer 1

E:the participants are different in the two conditions.this means that participant evs such as gender and age can influence the DV and could become confounding.

Question 2

strength of repeated measures:controls for participant EVs

Answer 2

E:participants take part in both conditions meaning there is no risk of participant EVs. this helps strengthen the study internal validity as it prevents participant evs becoming confounding.

Question 3

limitation of repeated measures: vulnerability to order effects.

Answer 3

E:Participants take part and both conditions. This means that they will always complete one of the conditions first and the other second. It’s possible that the order in which they complete the conditions could influence the dependent variable. For example, they may become bored the second time.This undermines internal validity.

Question 4

strength of matched pairs:ability to control for participant extraneous variables

Answer 4

E:participants in each condition are carefully matched on variables like age and intelligence.This matching helps reduce differences between the conditions, making participant extraneous variables becoming confounding less likely.This strengthens the internal validity.

Question 5

limitation of matched pairs:it doesn’t offer a perfect control for participant extraneous variables

Answer 5

E:matched variables doesn’t mean identical in every way. this means there can be some unmatched (e.g.IQ). as a result, it’s possible for participant EVs becoming confounding and undermining the study’s internal validity.