To Construct an Interval Estimate for the Difference Between the Means

question 91

Multiple Choice

To construct an interval estimate for the difference between the means of two populations when the standard deviations of the two populations are unknown and it can be assumed the two populations have equal variances, we must use a t distribution with let n1 be the size of sample 1 and n2 the size of sample 2)

• A) n1 + n2) degrees of freedom
• B) n1 + n2 - 1) degrees of freedom
• C) n1 + n2 - 2) degrees of freedom
• D) n1 - n2 + 2

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Definitions:

Antidrug Norms

Societal standards and beliefs that oppose the use of illegal drugs and support behaviors that resist drug use.

Drug Problems

Issues arising from the abuse or dependency on illegal drugs or the misuse of prescription medications, leading to personal, social, or health consequences.

Internalizing Problems

Refers to psychological struggles that manifest internally, such as anxiety, depression, and excessive worry, often leading to withdrawn or inhibited behavior.

Cognitive-behavioral Therapy

A form of psychotherapy that focuses on changing negative thought patterns and behaviors that contribute to psychological distress.