In looking at the sampling plan of a study, the reviewer knows ...

[kellyjaisingh]

In looking at the sampling plan of a study, the reviewer knows that the sample size needed for a study increases when the:
 
  a. alpha level is increased from 0.01 to 0.05.
  b. number of variables in the study increases.
  c. one-tailed versus two-tailed statistical test is used.
  d. sensitivity of the instruments used is high.

Question 2

Which of the following best describes the following hypothesis: Teenagers who have a high self-concept will be less likely to diet than those with a low self-concept?
 
  a. Associative, complex
  b. Causal, nondirectional
  c. Complex, directional
  d. Simple, directional

[laurnthompson]

Answer to Question 1

ANS: B
As the number of variables under study increases, the sample size needed may increase.
The reverse of this statement is true. As the number of variables under study increases, the sample size needed may increase.
One-tailed tests do not require as large a sample as two-tailed tests. As the number of variables under study increases, the sample size needed may increase.
High sensitivity of the instruments can allow for a smaller sample size. As the number of variables under study increases, the sample size needed may increase.

Answer to Question 2

ANS: D
The hypothesis is simple because there are only two variables, and it is directional since less likely is included.
Causation is not predicted, so it is associative, and there are only two variables, so it is a simple hypothesis.
There is no prediction of causation in the hypothesis, but the hypothesis indicates a direction, less likely, so it is directional.
There are more than two variables involved, so it is a complex hypothesis. The hypothesis indicates a direction, less likely, so it is directional.