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# Homework 2

##### Due on canvas Oct 16

This homework uses the same data as Lab 2, except I’ve taken a subsample of 1000 people. To get the data and store it in cdc, add this to the start of your script:

(This code is reading a comma delimited file from my website, you’ll need to be connected to the internet for it to work.)

# 1 Summary statistics

a. Calculate a new column, called wt_diff, for the difference between the subjects weight (weight) and their desired weight (wtdesire) using the following code.

b. Report summary statistics (average, standard deviation and sample size) of weight and desired weight for males and females separately.

c. Construct a histogram of wt_diff for females only, and describe it in context of the data.

d. Construct a plot with separate histograms of weight for males and females. Don’t forget to play with binwidth, but only include one plot your report.

# 2 Paired t-test

Conduct a paired t-test comparing the weight (weight) and the desired weight (wtdesire) for females only. Report your results in a statistical summary, the summary should include a sentence describing the result of the test, a sentence interpreting the point estimate, and a sentence interpreting the confidence interval.