A Researcher Wants to Conduct a Before/after Study on 11

question 12

Multiple Choice

A researcher wants to conduct a before/after study on 11 subjects to determine if a treatment results in any difference in scores.The null hypothesis is that the average difference is zero while the alternative hypothesis is that the average difference is not zero.Scores are obtained on the subjects both before and after the treatment.After subtracting the after scores from the before scores, the average difference is computed to be -2.40 with a sample standard deviation of 1.21.Assume that the differences are normally distributed in the population.The degrees of freedom for this test are ___.

• A)11
• B)10
• C)9
• D)20
• E)2

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Definitions:

Recreational Drugs

Substances taken for pleasure or leisure purposes, rather than for medical reasons, which can include alcohol, tobacco, and illegal drugs.

STIs

Short for Sexually Transmitted Infections, diseases that are primarily spread through sexual contact, including chlamydia, gonorrhea, and HIV.

Eating Disorders

Mental disorders characterized by abnormal eating habits that negatively affect a person's physical or mental health.

Self-esteem

An individual's subjective evaluation of their own worth, encompassing beliefs and emotions about oneself.