If the Mean of the Distribution of Differences Were to Equal

question 117

Multiple Choice

If the mean of the distribution of differences were to equal -6.00, this would indicate that

• A) the standard deviation of the distribution is a function of the range
• B) the samples probably represent different populations
• C) the samples were probably selected from a single population
• D) none of these, since the mean can never be negative

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Definitions:

Placebo Effect

A phenomenon where an individual experiences a perceived or actual improvement in a medical condition after receiving a placebo or inactive treatment.

Double-blind Experiment

A double-blind experiment is a research design in which both the participants and the experimenters are unaware of who is receiving the treatment or control, to prevent bias.

Statistically Significant

A determination that an observed effect is unlikely to have occurred by chance, based on a predetermined significance level.

Dependent Variable

The variable that is the subject’s response to, and dependent on, the level of the manipulated independent variable.