When Testing the Difference Between Two Population Means Under Independent

question 30

Multiple Choice

When testing the difference between two population means under independent sampling, we use the z distribution if ________.

• A) the population variances are known
• B) the population variances are unknown, but assumed to be equal
• C) the population variances are unknown and cannot be assumed equal
• D) Both the population variances are known and the population variances are unknown, but assumed to be equal

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Definitions:

Participant Modeling

Technique in which a model demonstrates the desired behavior in a step-by-step, gradual process while the client is encouraged to imitate the model.

Systematic Desensitization

is a behavioral therapy technique used to reduce fear or anxiety by gradually exposing the patient to the fear object or context.

Extinction

In psychology, the gradual weakening and eventual disappearance of a conditioned response when the conditioned stimulus is no longer paired with the unconditioned stimulus.

Eye-Movement Desensitization

a component of EMDR therapy focusing on alleviating the distress associated with traumatic memories through guided rapid, rhythmic eye movements.