STAT 1124
Solution to Project 2
Marks Distribution
Question# 1 2 3 4 5 6 7 8 9 10 11 Total
Marks
4 3 2 1 3 4 4 3 4
4 4
/36
Relating Alcohol Consumption to Blood Alcohol Content
Two universities conducted experiments to investigate the relationship between
Stats 1124
Solution to HW2
You may do this HW in pairs. If you do so, please hand in only one paper with both your names on it.
As part of a study on transportation safety, the U.S. Department of Transportation collected data on
the number of fatal accide
STAT 1124
Midterm 1 Solution
Question #
1
2 3 4 5 Total
Marks
11 10 6 7 7
/41
1. Viewers of youtube videos who have signed up for an account may vote for each video they watch
(like or dislike). The data are then compiled to rate the videos.
a. Describe t
STAT 1124
HW 1 Solution
Total no. of marks: 25
Babies born with a low birth weight have higher rates of infant mortality and birth defects. This study
looks at factors that may influence birth weight. The data (birthweight.sgd) and its full description
(b
Stats 1124
HW2
Instructions:
Write your answer clearly and legibly, or type it, on your answer sheets.
Hand in your HW on the due date in class, in hard copies.
You may do this HW in pairs. If you do so, please hand in only one paper with both your nam
STAT 1124
Quiz 5 Solution
1. Data on the consumption of ice cream in a certain city over a thirty-month period are summarized
below.
Y = consumption per capita in litre/month
X = average monthly temperature in 0C.
Summary Statistics
Y
X
Count
30
30
Averag
STAT 1124
Quiz 4 Solution
1. Does exposure to classical music (through lessons or concert attendance) improve childrens
scholastic performance? In a study, researchers measured the amount of exposure to classical music,
along with their scores on academic
STAT 1124
HW 1
Instructions:
You may do this HW in pairs. If you do so, please hand in only one HW with both your names
on it.
Please hand in a typed hard copy with StatGraphics output integrated with your answer. That is,
do not put all the StatGraphics
STAT 1124
Quiz 1 Solution
Refer to the following situation to answer questions 1 5:
A yoga studio provides survey forms on which patrons can give feedback. One of the
questions on the survey form is "Are you a member?" (Patrons are made up of members and
STAT 1124
Quiz 2 Solution
1. A marketing class designs two advertising videos for a luxury sport car, video A and video
B. They test the videos by asking their fellow students to watch one of the two videos, chosen
at random, and then ask them to rate the
STAT 1124
Quiz 3 Solution
Data on alcohol consumption (recorded as litres per year per person over the age of 15) from all the
190 countries of the world, collected by WHO are summarized below.
Count
Average
Median
Standard deviation
Minimum
Maximum
Lower
STAT 1124
QUIZ 6 Solution
1. A truckload of apples arrive at a packing plant. A sample of 200 apples are selected for inspection. If
more than 6% of the ones in the sample have bruises, discolouration, or other defects, the whole
truckload will be rejecte
Inference About Two Means
Chien-Hsun Chang
1
Inference About Two Means
Inference About Two Means Using z
Procedure
Inference About Two Means Using t
Procedure
2
Inference About Two Means Using z
Procedure
Confidence Interval About Two Means with 1
and
Nonparametric Tests
Chien-Hsun Chang
1
Parametric Tests vs. Nonparametric
Tests
Parametric tests are statistical tests such as z, t,
and F tests that have requirements about the
shape of the populations involved (i.e., populations
are normally distributed
Inference for Mean
Chien-Hsun Chang
1
Inference for Mean
Inference for Mean Using z procedure
Inference for Mean Using t procedure
2
Inference for Mean Using z
Procedure
Confidence Interval for Mean
Hypothesis Testing for Mean
3
Requirements for z Procedu
Simple Linear Regression
Chien-Hsun Chang
1
Simple Linear Regression vs.
Multiple Linear Regression
In a simple linear regression, there is only one
independent variable (also called an explanatory
variable) that is used to predict the dependent
variable
EXAMPLE 1.1
a) The best point estimate of the population mean is the sample mean. So X 16.6
hours.
b)
the average number of hours per week that the ninth-grade students play
online games
1 0.95 0.05
z 2
n
1.96
z0.05 2 z0.025 1.96
2.8
0.928
35
16.6 0
One-Way ANOVA
Chien-Hsun Chang
1
Introduction
The F test, which is used to compare two
population variances, can also be used to
compare three or more population means.
The F test can only show whether a difference
exists among the means being compared.
Table 1: Area on Selling Price
Independent variable: Area
Coefficients
Least Squares
Parameter Estimate
Intercept 133936.
Slope
101.408
Standard
Error
26485.9
12.2707
Analysis of Variance
Source
Sum of Squares
Model
1.7361E11
Residual
9.65948E10
Total (Co
Multiple Linear Regression
Chien-Hsun Chang
1
Multiple Linear Regression
In simple linear regression, the regression
equation contains one independent variable x
and one dependent variable y. The equation is
y b0 b1 x
In multiple linear regression, ther
EX 10.1 Height of Daughter
Multiple Regression - Daughter
Dependent variable: Daughter
Independent variables:
Mother
Father
Number of observations: 20
Parameter
CONSTANT
Mother
Father
Estimate
7.4543
0.707206
0.163629
Standard
Error
10.8804
0.128858
0.126
EXAMPLE 2.1
a)
p the proportion of students who pay their education by student loans
b)
n 1404 30
c)
p
323
0.2301
1404
1 0.9 0.1
z 2
n1 p 1081 5
np 323 5
z0.05 1.645
p 1 p
1.645
n
0.23011 0.2301 0.0185
1404
0.2301 0.0185 p 0.2301 0.0185
0.212 p 0.249
Inference About Two
Proportions
Chien-Hsun Chang
1
The Sampling Distribution of p 1 p 2
For independent samples of size n1 and n2 from
two populations, the sampling distribution of the
difference between the two sample proportions is
approximately normall
EX 8.1 Weight Gains of Athletes
Box-and-Whisker Plot
Diet A
Diet B
Diet C
0
3
6
9
Weight Gain of Athletes (lb)
12
15
Normal Probability Plot
99.9
n:4
Median:5.0
Sigma:2.22222
99
percentage
95
80
50
20
5
1
0.1
3
4
5
Diet A
6
7
1
Normal Probability Plot
99.
Inference for Proportion
Chien-Hsun Chang
1
Inference for Proportion
Confidence Interval for Proportion
Hypothesis Testing for Proportion
2
Population Proportion vs. Sample
Proportion
Consider a population in which each member
either has or does not hav
EXAMPLE 0.1
a) The sampling distribution of the mean IQ of 4 people is a normal distribution with
X 100 and X
n
16
8.
4
b) The sampling distribution of the mean IQ of 16 people is a normal distribution with
X 100 and X
c)
16
4.
n
16
X the average IQ
Sampling Distributions and
Central Limit Theorem
Chien-Hsun Chang
1
Question: Suppose IQs are normally distributed
with a mean of 100 and a standard deviation of 16.
Draw a random sample of 4 IQs and compute the
sample mean. Repeat this process indefinite
Inference for Two-Way Tables
Chien-Hsun Chang
1
Inference for Two-Way Tables
Chi-Square Test for Comparing Two
Proportions
Chi-Square Test for Comparing More
Than Two Proportions
2
Two-Way Tables
A frequency distribution for bivariate data is called
a t
EX 9.1 Test Score vs Hours Studied
Simple Regression - Score vs. Hours
Dependent variable: Score
Independent variable: Hours
Linear model: Y = a + b*X
Coefficients
Least Squares
Parameter Estimate
Intercept
94.867
Slope
-0.845606
Standard
Error
4.30409
0.