SCENARIO 12-10
One Criterion Used to Evaluate Employees in the Assembly

question 130

Short Answer

SCENARIO 12-10
One criterion used to evaluate employees in the assembly section of a large factory is the number of
defective pieces per 1,000 parts produced. The quality control department wants to find out whether
there is a relationship between years of experience and defect rate. Since the job is repetitious, after
the initial training period any improvement due to a learning effect might be offset by a loss of
motivation. A defect rate is calculated for each worker in a yearly evaluation. The results for 100
workers are given in the table below. $$\begin{array} { r r | c c c } & &{ \text { \quad\quad\quad Years Since Training Period } } \\& & < 1 \text { Year } & 1 - 4 \text { Years } & 5 - 9 \text { Years } \\\hline \hline{ \text { Defect Rate: } } & \text { High } & 6 & 9 & 9 \\& \text { Average } & 9 & 19 & 23 \\& \text { Low } & 7 & 8 & 10\end{array}$$
-Referring to Scenario 12-10, find the rejection region necessary for testing at the 0.05 level of significance whether there is a relationship between defect rate and years of experience. a) Reject $H _ { 0 }$ if $\chi ^ { 2 } > 16.919$
b) Reject $H _ { 0 }$ if $\chi ^ { 2 } > 15.507$
c) Reject $H _ { 0 }$ if $\chi ^ { 2 } > 11.143$
d) Reject $H _ { 0 }$ if $\chi ^ { 2 } > 9.488$

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Definitions:

Vasopressin

A hormone also known as antidiuretic hormone (ADH) that regulates water balance in the body and constricts blood vessels, playing a key role in maintaining blood pressure.

Luteinizing Hormone

A hormone produced by the anterior pituitary gland that helps regulate the menstrual cycle and egg production (ovulation) in females, and sperm production in males.

Blood Sugar

The concentration of glucose present in the blood, crucial for maintaining energy levels and physiological functions.

Thyroid Gland

An endocrine gland located in the neck that produces hormones regulating metabolism, energy generation, and the body's sensitivity to other hormones.