STAT 110 ~ Homework #2 (Due Sunday, September 4th) (58 points)
1. Hodgkin’s Disease and Response to Treatment
In this study, 538 individuals diagnosed with some form of Hodgkin’s Disease were randomly chosen. For each patient the histological type of Hodgkin’s they had was determined (LP = lymphocyte predominant, LD = lymphocyte depletion, NS = nodular schlerosis, and MC = mixed cellularity). Also, their ultimate response to treatment was observed (none = no response to treatment, partial = some positive results but not complete remission, positive = complete remission).
These data are contained in the file: Hodgkins.JMP
a) Construct an appropriate display of the histological types of these patients. What type of Hodgkin’s Disease is most prevalent and what percentage of Hodgkin’s patients do we estimate would have this type? What is the least common form? (2 pts.)
b) Construct an appropriate display of the response to treatment for these patients. What is the common outcome of treatment and what percentage of Hodgkin’s patients have this response to treatment? What response is least common? (2 pts.)
c) Are histological type and response to treatment related? To answer this question construct comparative bar graphs using Distribution along with the By option or by constructing a mosaic plot using the Fit Y by X option. Summarize your findings on the relationship between histological type and response to treatment based on these bar graphs in the form of a well-written paragraph. (4 pts.)
2. North Carolina Birth Data
This study focuses on North Carolina births for 2006. It includes data on the age, education level and marital status of the parents; sex and race of the child; prenatal medical care received; county and hospital of birth; information on the mother's reproductive history including number of previous pregnancies and live births; as well as statistics on the newborn. The data contained in this file represent a random sample of
n = 1000 live births in North Carolina. (Data File: NC Birth)
The variables in this data file are as follows:
· Month of birth 1 = January, …, 12 = December
· Gender Gender of infant (M or F)
· Race of child W = white, B = black, O = other
· Age of father if years (if known)
· Age of mother if years
· Education of father in years (if known)
· Education of mother in years
· Total number of pregnancies # of pregnancies, including this one
· Number of terminations # of previous abortion or fetal deaths
· Gestational age gestational age of infant at birth (months)
· Month of pregnancy prenatal 1 = first month, 2 = second month, etc.
care began
· Total number of prenatal visits number of doctor visits prior to delivery
· Marital status Married or Single
· Birth weight (g) Birth weight of infant in grams
· Low birth weight Birth weight < 2500 grams (Y or N)
· Smoking status Smoking status of mother during pregnancy
· Pounds gained during pregnancy Mother’s weight gain during pregnancy
(lbs.)
· Induced Labor Mother had labor induced (Y or N)
· Vaginal Delivery Infant was delivered vaginally (Y or N)
· Gestational age Gestational age on birth certificate
· APGAR score (1 min) APGAR score one minute after delivery
(7 or above is considered good health)
· APGAR score (5 min) APGAR score five minutes after delivery
(7 or above is considered good health)
· Kotelchuck Index Another prenatal care score
0 = no prenatal care
1 = inadequate care
2 = intermediate care
3 = adequate care
4 = adequate plus
Questions and Tasks for Problem 2
a) What percentage of infants sampled were delivered via a C-section? (1 pt.)
b) Use these data to estimate the percentage of infants born in North Carolina that are classified as having a low birth weight, i.e. a birth weight less than 2,500 grams? (1 pt.)
c) What percentage of infants were born to mothers who smoked during pregnancy? (1 pt.)
d) Compare the percentage of infants born with low birth weights to women who smoked during pregnancy to those born to women who did not smoke during pregnancy. What do you conclude from this? (3 pts.)
e) What percentage of infants were born to women who are not married? (1 pt.)
f) What percentage of women had a previously terminated pregnancy? (2 pts.)
g) What percentage of women had prenatal care that began during the first trimester of their pregnancy, i.e. in the first three months? (2 pts.)
h) What percentage of women had at least adequate prenatal care according to the Kotelchuck Index? (2 pts.)
i) One would expect that births would be uniformly distributed throughout the year. Looking at the Month of birth variable does this appear to be the case? Explain. (2 pts.)
j) One would expect that 50% of infants born would be female and 50% would be male. Does this appear to be the case? Explain. (2 pts.)
k) Construct a display to compare the percentage of infants born with low birth weights to smokers vs. non-smokers. Discuss any apparent differences. (3 pts.)
l) Construct a display to compare the percentage of infants born with low birth weight across race. Discuss any apparent differences. (3 pts.)
m) How would you characterize the distribution of birth weight? What would be a typical birth weight? Were there outliers and if so were most of them on the low or high end? (3 pts.)
n) How would you characterize the distribution of the number of pregnancies? What would be a typical number of prior pregnancies? (2 pts.)
o) How would you characterize the distribution of the number of prenatal visits? What would be a typical number of prenatal visits? (2 pts.)
p) Construct a plot and obtain summary statistics that can be used to compare the birth weights of infants born to mothers who smoked during pregnancy to infants born to mothers who did not smoke during pregnancy. Summarize the important results from your analysis in a well-written paragraph. Be sure to include supporting statistics in your discussion. (10 pts.)
q) Using JMP obtain summary statistics to complete the table below using birth weight in grams as the response of interest. Summarize any notable differences in birth weight across the levels of these demographics. (10 pts.)
Demographic / Sample size(n) / Sample mean
/ Sample SD
(s)
Race of infant
Black
Other
White
Gender of infant
Female
Male
Marital status
Married
Single
1