TABLE 12-13
According to an Article in Marketing News, Fewer

question 136

Short Answer

TABLE 12-13
According to an article in Marketing News, fewer checks are being written at grocery store checkout stands than in the past. To determine whether there is a difference in the proportion of shoppers who pay by check among three consecutive years at a 0.05 level of significance, the results of a survey of 500 shoppers in three consecutive years are obtained and presented below.
$$\begin{array}{l}\text {\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad Year }\\\begin{array} { c | c | c | c } \text { Check Written } & \text { Year 1 } & \text { Year 2 } & \text { par 3 } \\\hline \text { Yes } & 225 & 175 & 125 \\\text { No } & 275 & 325 & 375\end{array}\end{array}$$
-Referring to Table 12-13, what are the degrees of freedom of the test statistic?

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Definitions:

First-Order Autocorrelation

The correlation between values in a time series and the values immediately preceding them.

Durbin-Watson Statistic

A measure used to detect the presence of autocorrelation in the residuals from a regression analysis.

Hypotheses Testing

A method in statistics that applies data from a subset to assess assumptions about a broader population's characteristic.

Durbin-Watson Test

A statistical procedure aimed at discovering the presence of autocorrelation at the first lag within the residuals of a regression analysis.