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Statistics 110
Homework 1
You are allowed to discuss problems with other students, but the nal answers must be
your own work.
For all problems that require calculation, Y
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FIRST NAME (Please Print):
HONOR PLEDGE (Please Sign):
Statistics 111
Midterm 3
This is a closed book exam.
You may use your calculator and a single page of notes.
The room is crowded. Please be careful to look only at you
LAST NAME (Please Print): KEY
FIRST NAME (Please Print):
HONOR PLEDGE (Please Sign):
Statistics 111
Midterm 1
This is a closed book exam.
You may use your calculator and a single page of notes.
The room is crowded. Please be careful to look only at you
LAST NAME (Please Print):
FIRST NAME (Please Print): KEY
HONOR PLEDGE (Please Sign):
Statistics 111
Homework 3
You are allowed to discuss problems with other students, but the nal answers must be
your own work.
For all problems that require calculation, Y
LAST NAME (Please Print): KEY
FIRST NAME (Please Print):
HONOR PLEDGE (Please Sign):
Statistics 111
Midterm 3
This is a closed book exam.
You may use your calculator and a single page of notes.
The room is crowded. Please be careful to look only at you
LAST NAME (Please Print):
FIRST NAME (Please Print):
HONOR PLEDGE (Please Sign):
Statistics 111
Midterm 1
This is a closed book exam.
You may use your calculator and a single page of notes.
The room is crowded. Please be careful to look only at your ow
LAST NAME (Please Print): KEY
FIRST NAME (Please Print):
HONOR PLEDGE (Please Sign):
Statistics 111
Homework 2
You are allowed to discuss problems with other students, but the nal answers must be
your own work.
For all problems that require calculation, Y
LAST NAME (Print): KEY
Statistics 111
Quiz 13
1. Let X1 , . . . , Xn be a random sample from a distribution that is uniform between 0 and for > 0.
Let Y denote the maximum of the sample.
1/Y What is the maximum likelihood estimate of 1/?
From our maximum
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Statistics 111
Quiz 11
1. Let X1 , . . . , Xn be a random sample with density f (x) = c x(+1) for x > c with c > 0 and > 0.
Find the MLE of .
The likelihood function is
f (x1 , . . . , xn ; ) =
n
Y
c xi
(+1)
= n cn
i=1
n
Y
xi
(+1)
i
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FIRST NAME (Please Print):
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Statistics 111
Midterm 1
This is a closed book exam.
You may use your calculator and a single page of notes.
The room is crowded. Please be careful to look only at you
Professor David Banks
Stats-111 Lab - 8:30AM Friday
10 April 2015
1. A normal curve does not describe the distribution of per capita GNI well as through graphing
the data as a scatterplot, an obvious skew towards the left is observed.
2. Life Expectancy f
Professor David Banks
Stats-111 Lab - 8:30AM Friday
27 March 2015
1. Do juries appear to be randomly selected with respect to the distribution of age?
Sample and population percentages in each age group
Age
Sample % *
Population %
21-40
7.58
42
41-50
13.6
Typing pwd into the command line well tell you the current directory and can be used to
verify that you are in the right place
Type do example.do in the command line to open up do.le
Type the variable names after the sort command in the desired order. Alt
Professor David Banks
Stats-111 Lab - 8:30AM Friday
3 April 2015
1. The distribution of long-term interest rates is skewed right, with most values located at the
left of the distribution. There appears to be no clear outliers. The mean is 5.33 with a
stan
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Statistics 111
Quiz 15
1. Pea pod ination and color are Mendelian traits. Yellow (Y) is dominant to green (g); wrinkled
(W) is dominant to unwrinkled (u). Mendel crosses YYWW with gguu; all ospring are yellow
and wrinkled. He crosse
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Statistics 111
Quiz 14
1. You want to show that average starting salary of Duke graduates is more than $60K. A random sample
of 81 recent graduates has mean starting salary $63K with a standard deviation of $10K. In words,
what is y
NAME (Please Print): KEY
Statistics 111
Quiz 16
1. You do a regression analysis. The response variable is the average lifespan in a county, and the
explanatory variable is the average annual income in the county. The JMP output says the estimated
intercep
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HONOR PLEDGE (Sign):
Statistics 111
Quiz 6
1. The proportion of people who will vote for Donald Trump has the density f (x) = cx2 (1 x) (so it
takes a random value between 0 and 1).
12 What is the value of c?
1=c
R1
0
x2 (1 x) dx =
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Statistics 111
Quiz 7
1. Suppose f (x, y) = c for all (x, y) such that x2 + y 2 3. The following questions (except the last) can
be answered with minimal calculation, just geometry.
1/(3) What is the value of c?
The area of the circ
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Statistics 111
FIRST:
Quiz 8
1. Suppose f (x, y) =
4
x
81
for all (x, y) such that 0 < x < 3, 0 < y < 9, and y < 9 x2 .
2/81 What is the probability that both X and Y are between 0 and 1?
This is simple, since the region is a rectangle
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statistics 111
Quiz 5
0.75 1. In order to graduate, Aguinaldo must pass final exams in two of three classes. His probability of
passing the econ exam is 0.9; his probability of passing the statistics exam is 0.5; his probability of
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Statistics 111
Quiz 4
1. A spinner can land on red, yellow, blue or green. The probability of red is 1/3, the probability of
yellow is 1/6, and the probability of blue is 1/4.
0.25 What is the probability of green?
1 - 1/3 - 1/6 - 1
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Statistics 111
Quiz 1: This is practice, and will not be graded.
All answers must be correct to two decimal places.
1. Each assignment receives a letter grade. An A+ counts as 12, an A as 11, and so forth down to an F,
which counts
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Statistics 111
Quiz 2
Answers must round to two correct decimals.
1. A study found that people who drank white wine, rather than red wine, had better heart health.
Yes Was this an observational study?
What confounding variable might
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FIRST NAME (Please Print):
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Statistics 111
Homework 1
You are allowed to discuss problems with other students, but the final answers must be
your own work.
For all problems that require calculation,
FIRST NAME (Please Print): KEY
LAST NAME (Please Print):
HONOR PLEDGE (Please Sign):
Statistics 111
Homework 9
You are allowed to discuss problems with other students, but the nal answers must be
your own work.
For all problems that require calculation, Y
LAST NAME (Please Print): KEY
FIRST NAME (Please Print):
HONOR PLEDGE (Please Sign):
Statistics 111
Homework 8
You are allowed to discuss problems with other students, but the nal answers must be
your own work.
For all problems that require calculation, Y
LAST NAME (Print): KEY
Statistics 111
Quiz 20
1. You want to show that statistics majors have better starting salaries that econ majors. It is known
that starting salaries have a standard deviation of $10K and that econ majors have an average starting
sal
LAST NAME (Print): KEY
Statistics 111
Quiz 18
1. You fail statistics, unk out of Duke, and take a job as a carnie, guessing peoples weights. Their trick
is to have a pole or a tree behind the mark, with notches to show the marks height; they also have a
h
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Statistics 111
Quiz 17
1. Multiple regression on 18 students predicts nal grade (FG) from the hours spent studying the night
before the nal (NB), the hours spent studying the week before the nal (WB), and the number of
courses being
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FIRST NAME (Please Print):
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Statistics 111
Midterm 4
This is a closed book exam.
You may use your calculator and a single page of notes.
The room is crowded. Please be careful to look only at your ow
15.0 More Hypothesis Testing
1
Answer Questions
Type I and Type II Error
Power Calculation
Bayesian Hypothesis Testing
15.1 Type I and Type II Error
In the philosophy of hypothesis testing, the null hypothesis is innocent until
proven guilty. You requ
14.0 Hypothesis Testing
1
Answer Questions
Hypothesis Tests
Examples
14.1 Hypothesis Tests
A hypothesis test (significance test) is a way to decide whether the data
strongly support one point of view or another.
There are many kinds of significance tes
LAST NAME (Print):
Statistics 111
FIRST:
Quiz 11
1. Let X1 , . . . , Xn be a random sample with density f (x) = x1 for 0 x 1 with > 0. Find the
MLE of .
2. Let X1 , X2 , X3 be independent and suppose Xi is normally distributed with mean i and standard
dev
1
16. Contingency Tables & Goodness-of-Fit
2
Answer Questions
Tests of Independence
Goodness-of-Fit Tests
16.1 Tests of Independence
Often one has a sample of cases; each case can be categorized according to two
different criteria:
each person got the