Jake Snyder
Regression Analysis
6/14/12
Project 3
1. The weight has a mean of 141.67 with a standard deviation of 27.94 and a median of
138. It is normally distributed (as the tests for normality show) with a coefficient variation
of 19.72. The age has a
JakeSnyder
Project2
6/5/12
1.
4
4
4
3
3
3
g
p
g
p
2
a
g
p
2
a
1
1
2
4
6
8
1
10
4
6
hs m
4
g
p
2
2
a
1
1
400
600
800
sat m
(mean,standarddeviation,minimum,maximum)
GPA:2.64,0.78,0.12,4.00
HSM:8.32,1.642.00,10.00
HSS:8.09,1.70,3.00,10.00
HSE:8.09,1.51,3.00,
JakeSnyder
Project2
6/5/12
1.
4
4
4
3
3
3
g
p
g
p
2
a
g
p
2
a
1
1
2
4
6
8
1
10
4
6
hs m
4
g
p
2
2
a
1
1
400
600
800
sat m
(mean,standarddeviation,minimum,maximum)
GPA:2.64,0.78,0.12,4.00
HSM:8.32,1.642.00,10.00
HSS:8.09,1.70,3.00,10.00
HSE:8.09,1.51,3.00,
Stat 2118 Homework 4
The following table presents data on tar, nicotine, weight (in grams) and carbon monoxide
contents (in milligrams) for a sample of 25 (filter) brands of cigarettes tested in a recent year.
Tar (x1)
14.1
.
.
12.0
Nicotine (x2)
0.86
.
.
Quick Guide: Using SAS to Compute Matrices
Hiya, folks!
So the concept of matrices can get a little confusing for some, and in the real world, calculating
large data sets are just downright rough. That is why we try to incorporate some of the SAS
material
Final Practice Problems
Question 1
A company is interested in investigating the effect that its advertising expenditure has on its sales
revenue. Below is data giving the sales revenue (in tens of thousands of dollars) for a sample of
18 months, as well a
Final Practice Problems
Question 1
A company is interested in investigating the effect that its advertising expenditure has on its sales
revenue. Below is data giving the sales revenue (in tens of thousands of dollars) for a sample of
18 months, as well a
STAT 118 - Final
December 20, 2010
Name:
Student ID #:
This is an open book, open notes exam; you may use a calculator. You can use a sheet with the
formulas you may need. Show your work to receive full credit. All questions carry the same
points (4 pts).
Identifying Outliers
Twenty healthy female subjects take part in a study to relate the fraction of body fat (Y) to tricep
thickness (X1), thigh circumference (X2), and midarm circumference (X3).
PROC REG DATA=bodyfat;
MODEL fat = tricep thigh / INFLUENCE
THE GEORGE WASHINGTON UNIVERSITY
Department of Statistics
STAT 2118: Regression Analysis, Fall 2016
SYLLABUS
Course and Contact Information
Course: STAT 2118-10 Regression Analysis
Semester: Fall 2016
Lecture: Monday and Wednesday, 11:10am 12:25pm
Locatio
Multiple Linear Regression: Stepwise Methods
For the cigarette data, use the subset method to determine the best first order model.
PROC REG DATA=cigarette;
MODEL carbon = tar nicotine weight / SELECTION=CP;
RUN;
Number
in
Model
C(p)
R- Variables in Model
One Sample Hypothesis Test Example
A school is interested in this years test scores. In previous years the mean test score has
been 20 (out of 25) and so the schools administrators would like to see if the mean test
score has changed. They take a sample o
Matrix notes:
1. Transpose Matrix
A new matrix that obtained by using rows from the first matrix as the columns in the
second matrix
A
Dimension has reversed
2. Vectors
One column or one row
Column vectors and row vectors
a ( column vector), a (row
Sparks STA 2118
Optional: Calculator Tricks
When performing simple linear regression estimates by hand, it can get super long and tedious. However,
calculating things like sums of squares can be simplified a little bit through a little bit of algebra. Thi
T-Tests in SAS
1. One-sample T-Test
2. Matched Pairs T-Test
3. Two-sample T-Test
Introduction
Suppose you want to answer the following
questions:
Does a new headache medicine provide the
typical time to relief of 100 minutes, or is it
different?
Does a
STAT 2118: Important Formulas and Notes
1. Simple Linear Regression means using one explanatory variable to predict an independent
variable. Mathematically, it takes the form
= 0 + 1 + ,
for = 1, ,
2. In practice, we observe all of the and but we do not
Practice Problems: Simple Linear Regression
Researchers interested in determining if there is a relationship between death anxiety
and religiosity conducted the following study. Subjects completed a death anxiety
scale (high score = high anxiety) and also
Homework 1 Modified Questions:
1. What is the t-statistic in Q1(a)? (2 decimal places)
2. What is the t-critical value in Q1(a)? (2 decimal places)
3. What is the p-value in Q1(b)? (3 decimal places)
4. What is the upper bound in Q1(c)? (2 decimal places)
Stat 2118 Homework 2
Question 1vf
In a study, the protein absorption (Y) for seven concentration levels (X) of that protein
were measured:
Conc. Level (Xi)
6
8
10
12
14
16
18
Absorption (Yi)
10
15
18
18
24
22
26
a) Find the least squares estimate for the
Stat 2118 Homework 8
For this homework use the data set senic.xlsx, which is on blackboard. This data set consists of a
random sample of 113 hospitals. The objective is to study the infection risk and what factors
influence it. The variables from the data
Multiple Linear Regression: Multicollinearity Example
The following table presents data on tar, nicotine, weight (in grams) and carbon
monoxide contents (in milligrams) for a sample of 25 (filter) brands of cigarettes tested in
a recent year.
Tar (X1)
14.
Stat 2118 Homework 7
An economist is investigating the relationship between the size of an insurance firm and
the speed at which they implement new insurance innovations. He believes that the type
of firm may affect this relationship and suspects that the
proc reg data=children;
model weight = age / xpx i covb;
run;
Model Crossproducts X'X X'Y Y'Y
Variable
Intercep
t
age
weight
Intercep
t
19
253
1900.5
253
3409
25760
1900.5
2576
0
199435.7
5
age
weight
X'X Inverse, Parameter Estimates, and SSE
Variable
Int
Multiple Linear Regression: First Order Example
A collector of antique grandfather clocks knows that the price received for the clocks
increases linearly with the age of the clocks. Moreover, the collector hypothesizes that the
auction price of the clocks
Stat 2118 Midterm Examination II .Name: Theme 6
April 8, 2015 ID#: &M>&, 0?
Please show your work to receive full credit. Specify the null and alternative hypotheses
for all tests you perform.
.4 v1 1
l. The following table gives the salarie; and gender f
Stat 2118 Midterm Examination II .Name: Theme 6
April 8, 2015 ID#: &M>&, 0?
Please show your work to receive full credit. Specify the null and alternative hypotheses
for all tests you perform.
.4 v1 1
l. The following table gives the salarie; and gender f
STAT 2118: Important Formulas and Notes
1. Simple Linear Regression means using one explanatory variable to predict an independent
variable. Mathematically, it takes the form
= 0 + 1 + ,
for = 1, ,
2. In practice, we observe all of the and but we do not