Instruction 15-5
a Computer Used by a 24-Hour Banking Service

question 13

Multiple Choice

Instruction 15-5
A computer used by a 24-hour banking service is supposed to randomly assign each transaction to one of five memory locations. A check at the end of a day's transactions gave the counts shown in the table to each of the five memory locations, along with the number of reported errors.
$$\begin{array} { | l | l | l | l | l | l | } \hline \text { Memory Location } & 1 & 2 & 3 & 4 & 5 \\\hline \text { Number of Transactions } & 82 & 100 & 74 & 92 & 102 \\\hline \text { Number of Reported Errors } & 11 & 12 & 6 & 9 & 10 \\\hline\end{array}$$ The bank manager wanted to test whether the proportion of errors in transactions assigned to each of the five memory locations differ.
-Referring to Instruction 15-5,which test would you use to properly analyse the data in this experiment?

• A) (?)² test for difference between two proportions
• B) ( ?)² test for difference among more than two proportions
• C) (?)² test of independence
• D) None of the above

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Definitions:

Positive Feedback

Put simply, success breeds success, failure breeds failure; the effect is seen with goods that are subject to network externalities.

Marginal Social Benefits

The additional benefits to society as a whole from producing one more unit of a good or service.

Socially Optimal Level

The level of output or activity where the benefits to society are maximized, taking into account both private and external costs and benefits.

Marginal Private Benefits

The additional satisfaction or utility gained by a consumer or firm from consuming or producing one more unit of a good.