## Description

Refer to the file “homework04data01.csv”, which can be found in the homework section of

Canvas, to answer Questions 1–4. This data set consists of antler-length data gathered

by zoologists. They are interested in seeing if we can use antler length (in inches) to

classify four species (a, b, c, or d for ease of notation).

1. Produce box plots, and based on those box plots, tell whether the four species’

antler lengths are different or not.

2. Use analysis of variance to test if there is a difference in mean antler length based

on species. Use α = 0.05.

3. From the Analysis of Variance results, identify and report SSE, SSTr, MSE, MSTr.

4. Construct 95% confidence intervals for each pair of species by using Tukey multiple

comparisons of means. Do any of the pairings imply a difference in average antler

length between species?

Refer to the file “homework04Hospital.csv”, which can be found in the homework section

of Canvas, to answer Questions 5–9. This data set presents data concerning the need for

labor in 17 hospitals. The main objective of the regression analysis is to evaluate the

performance of the hospitals in terms of how many labor hours are used relative to how

many labor hours are needed.

Here:

y: monthly labor hours required

x1: monthly X-ray exposures

x2: monthly occupied bed days

x3: average length of patients’ stays (in days).

5. Construct and solve a multiple linear regression model using this dataset. Identify

and report each coefficient (β estimate).

6. Interpret each coefficient.

7. Conduct a hypothesis test using α = 0.05 to see whether or not the predictor

BedDays is statistically significant. State the null and alternative hypotheses, the

test statistic, critical t-value, and your conclusion.

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8. Identify the p-value for testing the predictor Xray. By using the p-value and α =

0.05, state whether or not Xray is statistically significant. Would your answer be

different if α were 0.01?

9. Identify the p-value for testing the predictor Length. By using the p-value and α

= 0.05, state whether or not Length is statistically significant. Would your answer

be different if α were 0.10?