STAT 2215 CHAPTER 6
LINEAR COMBINATIONS AND MULTIPLE
COMPARISONS OF MEANS
Chapter 6 -
OVERVIEW
In the last chapter we discussed how to test the
equality of several group means. While these
tests are quite useful, they do not inform us
which groups have si
STAT 2215
Homework 1
Chapter 2 Problems 12, 13, 14, 15
Problem 12] Marijuana Use During Pregnancy. For the birth weights of babies
in two groups, one born of mothers who used marijuana during pregnancy and the
other born of mothers who did not (See Exerci
STAT 2215
Homework 6
Chapter 8 - Problem 23, Chapter 9 Problem 12, 14
Chapter 8
Problem 23] Wine Consumption and Heart Disease. The data in Display 8.21 are the
average wine consumption rates (in liters per person) and number of ischemic heart disease
dea
STAT 2215
HOMEWORK 3
Chapter 4 Problems 20, 21, 32
Zhidi zhang
Problem 20] Trauma and Metabolic Expenditure. For the data in Exercise 18 in Chapter 3:
Determine the rank transformations for the data.
(a) Calculate the rank-sum statistic by hand (taking th
STAT 2215
Homework 5
Chapter 7 Problems 12, 13, 15, 28
Problem 12] Suppose that the fit to the simple linear regression of Y on X from 6 observation
produces the following residuals: -3.2, 2.1, -4.0, -1.5, 5.1, 1.6.
(a) What is the estimate of 2?
15.3675
STAT 2215
Homework 4
Chapter 5 Problems 16, 17, 24
Problem 16] Spock Trial. Use a statistical computer package to obtain the analysis of variance
table in Display 5.10. Copy and Paste minitab outputs here.
Variable Judge N N* Mean SE Mean StDev Minimum Q1
STAT 2215Q
Homework #4
24. 1: the mean annual income in 2005 for 1st Quartile of IQ test taken in 1981
2: the mean annual income in 2005 for 2nd Quartile of IQ test taken in 1981
3: the mean annual income in 2005 for 3rd Quartile of IQ test taken in 1981
STAT 2215Q
Homework #2
12. (a) 95% CI: (188.5464, 371.4536)
Confidence interval conclusion: We are 95% confident that 2-1 lies in the interval (188.5464, 371.4536).
(b) 90% CI: (203.4776, 356.5224)
Confidence interval conclusion: We are 90% confident that
STAT 2215Q
Homework #1
16. (a)
This boxplot shows the gross domestic product per capita in 228 countries.
(b) Descriptive Statistics: PerCapitaGDP
Variable
PerCapitaGDP
N
228
N*
0
Mean
16018
SE Mean
1362
StDev
20567
Minimum
300
Q1
2825
Median
9300
Q3
2275
Chapter 2 - 1
STAT 2215 CHAPTER 2
T-TOOLS
Chapter 2 - 2
Inference Using t-distributions
This chapter focuses on t-tools
These tools are often used in statistics, to make
inferences about your data
An inference is the act of using a sample data
set to m
Chapter 7 - 1
STAT 2215 CHAPTER 7
SIMPLE LINEAR REGRESSION
Chapter 7 - 2
Recap from Previous Chapters
Chapters 1-5 covered methods for investigating the
relationship between a categorical (group) variable and a
numeric variable
One-Sample t-tools
Two-s
STAT 2215 CHAPTER 3
A CLOSER LOOK AT ASSUMPTIONS
Chapter 3 - 2
Recap
We previously covered some t-tools for
looking at the mean of a single group, or
comparing two groups.
One-Sample t-test, One-Sample t-interval
Matched Pairs t-test
Two-Sample t-test
Chapter 4 - 1
STAT 2215 CHAPTER 4
ALTERNATIVES TO THE T-TOOLS
Chapter 4 - 2
Chapter 4 Goals
Introduce some alternatives to the t-Tools
Four distribution-free methods
Permutation test and Rank-sum test
Two independent samples
Sign Test and Signed-Rank
Chapter 1 - 1
STAT 2215 CHAPTER 1
DRAWING STATISTICAL CONCLUSIONS
Chapter 1 - 2
The purpose of statistics is to examine data
to answer questions of interest.
Well focus on ways to make statistically
valid conclusions from data sets.
Statistical inferenc
STAT 2215 CHAPTER 5
COMPARISONS AMONG SEVERAL SAMPLES
Chapter 5 - 2
OVERVIEW
The previous tools weve seen are useful for
making inference about a single mean, or
comparing the means of two different groups.
But what if we have more than two groups?
Such a
STAT 2215
Homework 2
Chapter 3 Problems 20, 22, 24, 32
Problem 20]
Use a calculator to solve all questions in this problem. You may refer to page 8 of Chapter 3
Classnote. However, those results are not complete, you need to show your own work.
(a) Mean(i