Department Store
a Large Department Store Records the Number of Returns

question 90

Essay

Department store
A large department store records the number of returns per day in women's dresses for reasons such as wrong size; husband didn't like it,color,etc.The manager of the women's dresses department recalls from her statistics class in college that the Poisson distribution might describe such events.A random sample of 150 days is taken.The number of returns per day in the sample as well as the observed frequencies are shown below: $$\begin{array} { | c | c | } \hline \begin{array} { c } \text { Number of } \\\text { Returns Per Day }\end{array} & \begin{array} { c } \text { Observed } \\\text { Frequency }\end{array} \\\hline 0 & 21 \\1 & 37 \\2 & 44 \\3 & 30 \\4 & 14 \\> 4 & 4 \\\hline\end{array}$$
-She tests the hypothesis that returns per day are Poisson distributed with a population mean equal to 1.90.Her significance level is 0.05.Calculate the expected frequencies.

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Definitions:

Free Actions

Actions performed voluntarily without external coercion or determination, reflecting the agent's own choice or free will.

Freedom

The power or right to act, speak, or think as one wants without hindrance or restraint.

Intrinsic

Referring to something that is inherent or essential to the nature of something else, often used to describe values or properties that are an integral part of an object or concept.

Extrinsic

Not inherent or essential, coming from the outside, or external to something.