When individual differences such as intelligence and height are ...

[Lisaclaire]

When individual differences such as intelligence and height are examined in experiments, they are called
 
  a. control variables.
  b. cohort effects.
  c. regression artifacts.
  d. subject variables.

Question 2

Outline the major advantages and disadvantages of administering a survey by mail.
 
  What will be an ideal response?

[zhanghao]

Answer to Question 1

D

Answer to Question 2

Administering a survey by mail is convenient for the participants. They can respond at any time they choose and they can be assured of confidentiality. However, the researcher cannot be sure exactly who completed the survey. Also, the response rate to mail surveys is very low which can make the process expensive and can contribute to nonresponse bias. Nonresponse bias means that the people who choose to respond usually have strong opinions and therefore are often not representative of the rest of the population.

[Lisaclaire]

Thank you

[zhanghao]

No problem