A health magazine recently reported a study in which researchers ...

[lracut11]

A health magazine recently reported a study in which researchers claimed that iron supplements increased memory and problem-solving abilities in a random sample of college women. All of the women took memory and problem-solving tests at the beginning of the study, then took iron supplements, and then took the same tests again at the end of the study. What is wrong with this design? What confounds could be leading to the results of improved memory and problem-solving skills?
 
  What will be an ideal response?

Question 2

The most commonly used sampling methods in psychology are nonprobability sampling methods.
 
  a. True
  b. False
  Indicate whether the statement is true or false

[briseldagonzales]

Answer to Question 1

This is a single-group pretest/posttest design. In other words, there is no control group, and there should be a control group. The problem is that the subjects could have done any number of things between the pretest and posttest (in addition to taking iron supplements) that could have also led to this improvement. Thus, there could be a practice effect or a maturation effect.

Answer to Question 2

True

[lracut11]

Thanks for the timely response, appreciate it

[juliaf]

Excellent