In an Effort to Decide If There Is an Association

question 132

Essay

In an effort to decide if there is an association between the year of a postal increase and the new postal rate for first class mail, the data were gathered from the United States Postal Service. In 1981, the United States Postal Service changed their rates on March 22 and November 1. This information is shown in the table below.

$\begin{array}{|c|c|}\hline \text {Year} &\text { Rate} \\\hline 1971 & 0.08 \\\hline 1974 & 0.10 \\\hline 1975 & 0.13 \\\hline 1978 & 0.15 \\\hline 1981 & 0.18 \\\hline 1981 & 0.20 \\\hline 1985 & 0.22 \\\hline 1988 & 0.25 \\\hline 1991 & 0.29 \\\hline 1995 & 0.32 \\\hline\end{array}$

-Would it be better for customers for a year to have a negative residual or a positive residual from this model? Explain.

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Definitions:

Workplace Violence

Any act or threat of physical violence, harassment, intimidation, or other threatening disruptive behavior that occurs at the work site.

Cash Register

A machine used in businesses to calculate and record sales transactions, and to store money.

Immigrants

People who have moved to a country from one or more other countries, usually for permanent residence.

Delivery Firm

A business specialized in transporting documents, packages, or goods from one location to another.