experiment design Flashcards
independent group design?
participants places into separate groups, each group does 1 level of IV.
group 1 - completes homework with TV on.
group 2 - completes homework with TV off
researcher will then compare the performance of the 2 groups
weakness of independent group design?
researcher cannot control the effects of the participant variables (IQ, abilities, characteristics) and these could act as confounding variables.
example = someone in group 1 may have a learning difficulty and cannot answer the homework questions and nobody in group 2 has it. this impacts the results.
- 2 groups require more participants
how to solve the problems of independent group design?
randomly allocating participants to conditions to distribute variables evenly.
matched pair design?
2 groups of participants however they are based on the key characteristics relevant to the study
same IQ level for participant A in group 1 and participant A in group B. data then compared by the researcher
weakness of matched pair design?
very time consuming and fiddicult to match participants on key variables. Researcher cannot control all the variables as some maybe unknown.
how to deal with the problems on matched pair design ?
limiting the number of variables you are matching to make it easier. Conduct a pilot study to consider key variables that may be important when matching
repeated measures?
all participants receive all levels of IV
each participant does homework task with TV on, week later they do it with the TV off.
researcher then compares the performance of the DV for each participant on the 2 tests.
weakness for repeated measures?
the order you do the conditions could effect performance. Students may do better on the second homework task as they’ve done it before. However if they do worse it could be cause they are bored of doing it again. Participants may also guess the aim of the experiment when doing the second contain therefore change their behaviour.
how to steal with problems of repeated measures/
using 2 different tests and using them in both conditions. In order to stop/ prevent the participant guessing the aim of the study could be to create a cover story or use red-herrings.
