Question

1. After summarizing data collected to test a null hypothesis (e.g., observing z as a test statistic), a researcher fails to reject the null hypothesis (p > .05). The researcher then concludes that there is no treatment effect (treatment does not affect variation on the DV).

Is this a correct conclusion?
a. yes, it is correct
b. no, it is incorrect; a decision to fail to reject the null hypothesis results in ignorance about a treatment effect

35. Consider z as a test statistic stated in prose:
An observed variation on the DV adjusted by (divided by) Expected variation on the DV What is meant by Expected variation?

a. It is variation due to pure chance. b. It is random variation.
c. It is error variation.
d. It is nonrandom variation.

e. any of the above, except for d

36. A researcher has observed z as a test statistic. To evaluate the single probability of occurrence of observing z with a decision rule set at less than .05, the researcher uses the standard normal distribution (the SND, a normal distribution of z scores) as a test distribution.

How does the researcher know whether to consider one or two tails of the test distribution—that is, do a one-tail or two-tail test?

Tell the researcher to look at the

a. initial hypothesis (H1)

b. null hypothesis (Hø)

Answer 1

1.
b. no, it is incorrect; a decision to fail to reject the null hypothesis results in ignorance about a treatment effect

Fail to reject the null hypothesis suggests that we do do not have enough evidence to reject the null hypothesis. It does not say that the null hypothesis (no treatment effect) is true.

35.

The Expected variation is variation due to pure chance, random or error variation.

e. any of the above, except for d

36.

To decide for a one-tail or two-tail test, look at the initial or alternative hypothesis. If it has unequal operator () , it is non-directional or two-tail test. If it has < or > operator, it is directional or one-tailed test.

Tell the researcher to look at the

a. initial hypothesis (H1)