1. Chi-Square Tests (25 points)
A local manufacturing company is investigating the relationship between worker experience
level (Novice, Intermediate, Advanced) and the number of defects produced per shift. They
have collected data from a random sample of 150 workers for one week, categorized as
shown in the table below.
Worker Experience Number of Defects (0-2) Number of Defects (3+)
Novice 60 40
Intermediate 50 30
Advanced 40 30
a. Enter the data from the scenario into an Excel spreadsheet. Assign appropriate labels
for rows and columns.
b. State the null and alternative hypotheses for this scenario.
c. Calculate Chi-Square Statistic for the association between worker experience and the
number of defects (You may use the CHISQ.TEST function in Excel).
d. Set a significance level (alpha) of 0.05. Based on the calculated Chi-Square statistic,
can you reject the null hypothesis? Explain your answer in the context of the scenario.
e. Write a brief conclusion summarizing your findings. Does worker experience seem to
be related to the number of defects produced?
