A Statistic Professor Finds She Averages Five E-Mail Messages Per

question 63

Multiple Choice

A statistic professor finds she averages five e-mail messages per day from students. Assume the number of messages approximates a Poisson distribution. What is the probability that on a randomly selected day she will have two messages?

• A) 0.0067
• B) 0.0014
• C) 0.420
• D) 0.084
• E) 0.5

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Definitions:

Standard Deviation

A measure of the amount of variation or dispersion in a set of values, indicating how much the values differ from the mean.

Error Variable

A variable that quantifies the difference between observed and predicted values in a model or experiment.

Independent Variables

Variables in an experiment or statistical analysis that are manipulated or categorized to determine their effect on dependent variables.

Dependent Variable

The dependent variable is the variable in an experiment or model that is expected to change in response to changes in the independent variable.