Chapter 11

used frequently in problem or policy-oriented studies where the researcher is not interested in testing the statistical significance of the findings

• researchers have no clear idea what they may find
• they have no prior info to use for predictions
• search for data indications rather than to attempt to find causality
• gather preliminary data

• asks, "Do we have firm evidence that such-and-such is happening (or has happened)?"
• only different from research questions in that it predicts an outcome

• asserts that the statistical differences or relationships discovered in an analysis are due to chance or random error
• logical alternative to research hypothesis

a predetermined value against which the null hypothesis is tested

if the results of the study indicate a probability level lower than this level, the researcher can _____ the null hypothesis.

if the research outcome has a high probability, the researcher must _____ the null hypothesis.

• predicts that the results will fall in only one direction (either positive or negative)
• used when researchers have knowledge of the area and are able to more accurately predict the outcome of the study

• does not predict a direction
• used when little info is available about the research area

there is no difference in value between a study that finds _______________ results and a study that does not.

• the rejection of a null hypothesis that should be accepted
• under direct control of researcher

• the acceptance of a null hypothesis that should be rejected
• no direct control

• provides an estimate of the minimum number of respondents needed to provide the best chance to discover if something does or does not exist. 
• indicates the probability that a stat test of a null hypothesis will conclude that the phenomenon under study actually exists

• the degree to which the null hypothesis is rejected
• can be stated either generally or exactly
• the larger, the greater the degree to which the phenomenon is present

measures the effects size