Which of the Following Formulas Will Compute the Variance of a Discrete

question 43

Multiple Choice

Which of the following formulas will compute the variance of a discrete random variable X?

• A)\(\sum_{j=1}^{n}\left(x_{j}-E[X]^{2}\right)\)
• B)\(\sum_{j=1}^{\infty} \mathrm{E}[X]^{2} f\left(x_{j}\right)\)
• C)\(\sum_{j=1}^{\infty}\left(x_{j}-E[X]\right)^{2} f\left(x_{j}\right)\)
• D)\(\sum_{j=1}^{\infty}\left(x_{j}\right) 2 f\left(x_{j}\right)\)

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Definitions:

Social Validity

The degree to which the goals, procedures, and outcomes of an intervention are acceptable and relevant to the participants and their community.

Non-disturbed Samples

Samples collected from natural or unchanged settings or populations, maintaining their original conditions without human-induced alteration or manipulation.

Face Validity

The extent to which a test appears to measure what it's supposed to measure, based on subjective judgment.

Content Validity

When the content of a test includes a representative sample of behaviours thought to be related to the construct (that is, the concept or entity) the test is designed to measure.