Use the Data Given Below to Answer the Following Questions)

question 25

Essay

Use the data given below to answer the following questions).
The following extract from a manufacturer's database shows a sample of 10 suppliers, their transportation charges, and the estimated and actual total costs of supplying materials. Note: Assume a significance level of 0.05 wherever necessary.) $$\begin{array} { | l | c | c | c | } \hline \text { Supplier } & \begin{array} { c } \text { Transportation } \\\text { Charges }\end{array} & \begin{array} { c } \text { Estirnated Total } \\\text { Cost }\end{array} & \text { Actual Total Cost } \\\hline \text { Peter } & 340 & 4,500 & 4,680 \\\hline \text { Jdhry } & 560 & 4,500 & 4,790 \\\hline \text { Martin } & 480 & 4,500 & 5,110 \\\hline \text { Philip } & 290 & 4,500 & 4,780 \\\hline \text { Mark } & 370 & 4,500 & 4,810 \\\hline \text { Thomas } & 520 & 4,500 & 4,770 \\\hline \text { Jaison } & 350 & 4,500 & 5,250 \\\hline \text { David } & 430 & 4,500 & 4,930 \\\hline \text { Carter } & 510 & 4,500 & 5,010 \\\hline \text { Leonard } & 270 & 4,500 & 4,810 \\\hline\end{array}$$
-On studying the database, the manufacturer found out that the average difference between the estimated and actual total costs was $394. Based on the sample data, can the manufacturer conclude that the average difference between the estimated and actual total costs is different from zero?

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Definitions:

Hindsight Bias

The tendency to believe, after learning an outcome, that one would have foreseen it, also known as the "knew-it-all-along" effect.

Timing Bias

A form of cognitive bias where an individual's decisions or perceptions are influenced by the timing of information or events.

Base Rate Neglect

The tendency to ignore information about general principles in favor of very specific but vivid information.

Bonferroni Inequalities

Statistical safeguards used to reduce the chances of making incorrect inferences when multiple hypothesis tests are being performed simultaneously.