Lecture Notes for Stat 1000 by Dr. Nancy Pfenning
Note: Survey/article exercises must be handed in to me in lecture along with the textbook homework problems by the due date. They must be your own individual work. Each is worth a maximum of 2 points. For
Practice Quiz 11
Statistics 1000
Dr. Nancy Pfenning
1. (5 pts.) Some shoppers were observed in supermarket bakery departments that provided tongs and others were observed in departments that provided tissues. A researcher recorded how many people used the
Practice Quiz 5
Statistics 1000
Dr. Nancy Pfenning
1. (2 pts.) A survey in 2001-2002 found the following probability distribution for Americans number X of visits to the emergency room in the preceding year:
X
Probability
0
1
2
.78 .14 .04
3
4
5
.02 .01 .
Practice Quiz 4
Statistics 1000
Dr. Nancy Pfenning
1. (2 pts.) A large group of drivers participated in an online survey about their driving
habits. This table shows the probability of the respondents driving various types of
cars.
Type
Probability
Econom
Practice Quiz 3
Statistics 1000
Dr. Nancy Pfenning
1. (6 pts.) A used-car buyer compared prices of three-year-old Mercedes Benz and BMW
automobiles. These are displayed in a back-to-back stemplot, where leaves represent
thousands of dollars.
Mercedes
86 |
Practice Quiz 2
Statistics 1000
Dr. Nancy Pfenning
1. (7 pts.) This boxplot shows prices for adult weekend ski lift tickets in various resorts
in the Middle Atlantic States for the winter of 2004.
LiftTicketPrice
60
50
40
30
20
10
(a) The shape is (i) not
Practice Quiz 1
Statistics 1000
Dr. Nancy Pfenning
1. (5 pts.) An article entitled Moderate walking helps the mind stay sharper reports that
elderly people who walked at least ninety minutes a week were less likely to suer from
mental impairment than thos
Some Simple Analytics of Slave Redemption
Dean S. Karlan and Alan B. Krueger
Princeton University
The idea of purchasing the freedom of slaves is not new. Alexander Hamilton, for
example, helped found the Society for Promoting the Manumission of Slaves in
Supplement 10Chapter 4
A simple Bayes Rule problem, solved and explained
The Beardstown Bearcats baseball team plays 60 percent of its games at night and 40 percent in the daytime. It wins 55
percent of its night games but only 35 percent of its day games
Chapter 3: Describing Bivariate Data
Illustration: Gender vs Housework Study
Suppose a sociologist is interested in investigating the relationship between gender and amount
of time spent on housework for married couples. Assuming she has a sample of subje
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Outline
71 72 73 74 75
Confidence Intervals and Sample Size
Objectives
After completing this chapter, you should be able to 1. Find the confidence interval for the mean when s is known or n 30.
Correlation and Covariance
James H. Steiger
Goals for Today
Introduce the statistical concepts of
Covariance
Correlation
Investigate invariance properties
Develop computational formulas
Covariance
So far, we have been analyzing summary
statistics that de
_
Correlation
_
_
Greg C Elvers
_
1
_
What Is Correlation?
Correlation is a descriptive statistic that
tells you if two variables are related to each
other
_
E.g. Is your GPA related to how much you
study?
_
When two variables are correlated, knowing
the
Practice Quiz 8
Statistics 1000
Dr. Nancy Pfenning
1. (10 pts.) Number of calves sired by a sample of 10 captive Beluga whales had mean
1.5, standard deviation 1.4.
(a) Use the fact that the t multiplier for 9 degrees of freedom is 2.26 to set up a 95%
co
Practice Quiz 6
Statistics 1000
Dr. Nancy Pfenning
1. (5 pts.) The proportion of all assaults on U.S. law enforcement ocers that are made
with dangerous weapons (rearms, knives, etc. instead of hands, feet, sts, etc.) is
.20.
(a) What proportion should li
Practice Quiz 7
Statistics 1000
Dr. Nancy Pfenning
1. (5 pts.) In an Allegheny County Health Department survey, the proportion of respondents aged 18 to 29 who were sexually abstinent in 2002 was .06. Approximately 600
people in this age group were survey
Assignment 2 STAT 1000
1. A sample was taken of 20 salaries of employees in a large company. The following are the
annual salaries (in thousands of dollars. For convenience the data have been ordered.
28
31
34
35
37
41
42
42
42
47
49
51
52
52
60
61
67
72
Assignment 1 STAT 1000
1. Tell who or what individuals are being studied, identify the variable of interest, and tell whether
it is categorical or quantitative.
a. Adults were surveyed as to whether they were married, single, or divorced.
b. The New York
Assignment 4 STAT 1000
1. Lieutenant Edgar Beaver believes that officers who take masters-level courses receive higher
officer efficiency ratings (OERs). Using a sample of 100 Beaver regresses OERs (Y it ranges
from 0 to 100) on the number of courses each
Assignment 7 STAT 1000
1. For Stat 1000, the distribution of the midterm forms a normal population with = 80 and = 20.
a. What is the probability of selecting a student with a test score higher than 90?
b. What is the probability of obtaining a sample of
Assignment 6 STAT 1000
1. Spell-checking software catches nonword errors which result in a string of letters that is not a
word, as when the is typed as the. When undergraduates are asked to write a 250-word
essay (without spell-checking), the number X of
Assignment 3 STAT 1000
1. There are two major tests of readiness for college, the ACT and the SAT. ACT scores are
reported on a scale from 1 to 36. The distribution of ACT scores are approximately normal with
mean =21.5 and a standard deviation = 5.4. SAT
Assignment 5 STAT 1000
1. David Morgan, the city manager of Yukon, Oklahoma, must negotiate new contracts with both
the firefighters and the police officers. He plans to offer both groups a 7% wage increase and
hold firm. Mr. Morgan feels that there is on
Homework 5
Due: March 4, 2015
Name _
Class Time
10:00 AM
2:00 PM
3:00 PM
Recitation Day and Time _
Score _ /50
Problem 1 (7 points)
The Environmental Protection Agency (EPA) is concerned that the residue being dumped into a river by a
manufacturing compan
Practice Quiz 10
Statistics 1000
Dr. Nancy Pfenning
1. (10 pts.) Is there a signicant dierence in mean ages of students who identify themselves as vegetarians, non-vegetarians, or sometimes-vegetarians? Analysis of variance
was carried out on survey data
Practice Quiz 9
Statistics 1000
Dr. Nancy Pfenning
1. (5 pts.) Domestic goats follow gaze direction and use social cues in an object choice
task, published online in Animal Behavior in January of 2005, included information on
goats performance in a bucket
Statistics 1040
Dr. McGahagan
Spring 2011 -12
Biddle 124, MWF 11-11:50
Office: 122B Biddle Hall
E-mail: [email protected]
Web: www.pitt.edu/~upjecon
Office hours: MWF 9-10; TH 12-12:50
Statistics for Business and Economics
Prerequisites: Students are expe
Test of Hypothesis Examples Error Type I and Type II
Example 1: The Alpha-Fetoprotein (AFP) Test has both Type I and Type II error possibilities. This test
screens the mothers blood during pregnancy for AFP and determines risk. Abnormally high or low leve
Lecture 26
Nancy Pfenning Stats 1000
Chapter 12: More About Confidence Intervals
Recall: Setting up a confidence interval is one way to perform statistical inference: we use a statistic measured from the sample to construct an interval estimate for the un