Why do social scientists want to find the middle of a distribution in order to describe their data?

A. typically the extremes have higher frequencies of numbers than the middle

B. typically the middle has a higher frequency of scores than the extremes

C. it is easier to find the middle of a distribution than the extremes

D. because data in psychology is often not normally distributed

A researcher wants to know whether children who were breastfed during infancy perform differently on intelligence tests compared to children who were bottle-fed. What is the independent variable?

A. the bottle-fed group

B. different types of intelligence scores

C. intelligence tests

D. different types of feeding behavior

In the above question, what is the dependent variable?

A. depression scores

B. different types of feeding behavior

C. bottle-fed group

D. intelligence tests

Although researchers should always try and use random assignment to groups when conducting research, sometimes it is not practical, or ethical. Which of the following was mentioned in the online overview chapter as a widely used alternative?

A. single-subject design B. repeated-measures design

C. matched-group design

D. between-subjects design