Homework 7 (20 points)
STAT 301
Name(s) _____SOLUTION_________
Due: Thursday, April 11th @ 11:59pm
1. Thilothammal et al (Archives of Disease in Childhood, 1996) designed a study to determine the
efficacy of BCG (bacillus Calmette-Guerin) vaccine in preventing tuberculous meningitis. Among
the data collected on each subject was a measure of nutritional status (actual weight expressed
as a percentage of expected weight for actual height). The data can be found in the file
nutrition.jmp on the course website. You must paste or provided a detailed sketch of the JMP
output used to answer each question. (2 points each)
a. Find the average measure of nutritional status for the subjects. Be sure to use the
appropriate statistical notation in your answer.
x = 75.39
b. Find the range for the measure of nutritional status for the subjects. Be sure to show
how you computed this value.
Range = 130 – 45.6 = 84.4
c. Between what two values does the middle 99% of the values for the measure of
nutritional status fall?
Between 45.6 and 130 (i.e. the 0.5th and 99.5th percentiles)
d. Find the variance of the values for the measure of nutritional status for the subjects. Be
sure to use the appropriate statistical notation in your answer.
S2 = (13.64)2 = 186.05
e. Using JMP, create a histogram for the measure of nutritional status for the subjects.
Provide a detailed sketch of or paste your JMP output below.
1
f.
Looking at the histogram created in part e, describe the shape/distribution for the
measure of nutritional status.
Skewed Right
g. Using JMP, create a boxplot for the measure of nutritional status for the subjects.
Provide a detailed sketch of or paste your JMP output below.
h. Looking at the boxplot created in part g, are there any potential outliers? Explain.
Yes, because there are dots in the plot
2. Wright et al. (National Center for Health Statistics. Advanced Data from Vital and Health
Statistics, No. 334 2003) used the 1999 – 2000 National Health and Nutrition Examination
Survey (NHANES) to estimate dietary intake of 10 key nutrients. One of those nutrients was
calcium (mg). The calcium levels in men and women 60 years or older are summarized in the
following table:
Mean
Standard Deviation
Men
797
482
Women
660
414
Would it be more unusual to observe a male or a female with a calcium level of 315mg? Explain
your reasoning. (4 points)
z men =
315 - 797
= -1
482
z women =
315 - 660
-0.83
414
It would be more extreme to observe a male with a calcium level of 315 because it is further
from the mean than a woman with a calcium level of 315.
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