CourseKata - 4.15 Chapter 4 Review Questions 2

4.15 Chapter 4 Review Questions 2

NutritionStudy contains data for 315 patients at a hospital who had a noncancerous growth removed through surgery. It includes the following variables:

ID ID number for each subject in this sample
Age Subject's age (in years)
Vitamin Vitamin use: 1=Regular, 2=Occasional, or 3=No
Calories Number of calories consumed per day
Fat Grams of fat consumed per day
Fiber Grams of fiber consumed per day
Alcohol Number of alcoholic drinks consumed per week
Cholesterol Cholesterol consumed per day, in mg
Gender Coded as Female or Male
EverSmoke Smoking status: Never, Former, or Current

Here's the result from running head(NutritionStudy):

Data frame output
row	Age	Vitamin	Calories	Fat	Fiber	Alcohol	Cholesterol	Gender	EverSmoke
1	64	1	1298.8	57.0	6.3	0.0	170.3	Female	Former
2	76	1	1032.5	50.1	15.8	0.0	75.8	Female	Never
3	38	2	2372.3	83.6	19.1	14.1	257.9	Female	Former
4	40	3	2449.5	97.5	26.5	0.5	332.6	Female	Former
5	72	1	1952.1	82.6	16.2	0.0	170.8	Female	Never
6	40	3	1366.9	56.0	9.6	1.3	154.6	Female	Former

require(coursekata)

# run your code here

require(coursekata)

# run your code here

require(coursekata)

# run your code here

Now let's look at some data from the SleepStudy data frame. Here's the head() of the data frame, and then a description of the variables.

Data frame output
row	Gender	LarkOwl	NumEarlyClass	GPA	ClassesMissed	CognitionZscore	PoorSleepQuality	DepressionScore	Stress	Happiness
1	0	Neither	0	3.60	0	-0.26	4	4	normal	28
2	0	Neither	2	3.24	0	1.39	6	1	normal	25
3	0	Owl	0	2.97	12	0.38	18	18	normal	17
4	0	Lark	5	3.76	0	1.39	9	1	normal	32
5	0	Owl	0	3.20	4	1.22	9	7	normal	15
6	1	Neither	0	3.50	0	-0.04	6	14	high	22

Gender 1=male, 0=female
LarkOwl Early riser or night owl? Lark, Owl, or Neither
NumEarlyClass Number of classes per week before 9am
GPA Grade point average (0-4 scale)
ClassesMissed Number of classes missed in a semester
CognitionZscore z-score on a test of cognitive skills
PoorSleepQuality Measure of sleep quality (higher values are poorer sleep)
DepressionScore Measure of degree of depression
Stress Coded stress score: normal or high
Happiness Measure of degree of happiness (higher values are happier)
AllNighter Had an all-nighter this semester? 0 or 1

require(coursekata)

# run your code here

require(coursekata)

# run your code here

require(coursekata)

# run your code here

require(coursekata)

# run your code here

require(coursekata)

# run your code here

require(coursekata)

# run your code here

4.14 Chapter 4 Review Questions Part II: Modeling Variation