Research methods in psychology worksheet with answers

A researcher places an advert asking for people to take part in a study. Which sampling method is this?

1. AOpportunity sampling
2. BStratified sampling
3. CSystematic sampling
4. DVolunteer (self-selected) sampling

Test-retest reliability is assessed by:

1. AHaving two observers code the same behaviour
2. BChecking whether the items appear, on the surface, to measure what the test claims to
3. CGiving the same test to the same people on two occasions and correlating the scores
4. DComparing a new test with an established one

The median of the scores 3, 7, 8, 12, 20 is:

1. A7
2. B8
3. C10
4. D12

In a field experiment, the researcher:

1. AManipulates the IV in a laboratory
2. BManipulates the IV in a real-world setting
3. CAnalyses data collected by others
4. DOnly observes without manipulating anything

A Type I error occurs when a researcher:

1. ACollects too much data
2. BUses the wrong statistical test
3. CRejects a null hypothesis that is actually true
4. DFails to reject a null hypothesis that is false

A new depression questionnaire predicts which students will seek treatment over the next year. This supports which type of validity?

1. AContent validity
2. BConcurrent validity
3. CPredictive validity
4. DFace validity

Exercise reduces depression, and the effect occurs because exercise improves sleep, which in turn lowers depression. Sleep is best described as a:

1. AMediator
2. BModerator
3. CExtraneous variable
4. DControl variable

Increasing the sample size in a study most directly:

1. ARemoves all bias from the sample
2. BGuarantees a statistically significant result if any effect exists
3. CIncreases the effect size
4. DIncreases statistical power to detect a real effect