Choose the One Alternative That Best Completes the Statement or Answers

question 23

Multiple Choice

Choose the one alternative that best completes the statement or answers the question.
-A random sample of 40 part-time workers has a mean annual earnings of $\$ 3120$ and a population standard deviation of $\$ 677$ . Compute the $95 \%$ confidence interval for $\mu$ .

• A) \(( \$ 2910 , \$ 3330 )\)
• B) \(( \$ 210 , \$ 110 )\)
• C) \(( \$ 4812 , \$ 5342 )\)
• D) \(( \$ 1987 , \$ 2346 )\)

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Definitions:

External Validity

The extent to which the results of a study can be generalized or applied to other situations or to other people.

Internal Validity

The extent to which an experimental design accurately demonstrates a causal relationship between variables, without influence from external factors.

Causal Relationship

A causal relationship indicates a connection between two variables where changes in the value of one variable are known to cause changes in the value of another variable.

Demand Characteristics

Environmental cues in experiments that might influence participants' behavior or responses, potentially biasing the results.