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
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
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
blu49076_ch07.qxd
5/20/2003
3:15 PM
Page 325
c h a p t e r
7
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
Statistics 1040
Dr. McGahagan
Spring 2011 -12
Biddle 124, MWF 11-11:50
Office: 122B Biddle Hall
E-mail: mgahagan@pitt.edu
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
Types of Variables
Binary variable
Obsevations (i.e., dependent variables) that occur in one of two possible states, often labelled zero and one. E.g., "improved/not improved" and "completed task/failed to complete task." Usually an independent or predict
Spread of the Reformation
- October 31, 1517 Ninety-five theses
- Martin Luther the powerful intensively religious man.
- He trigged the start of reformation
- Wrote statements that were needed to be proven
- His statements were printed and spread around
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
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
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 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
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 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
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 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
John E. Freund s Mathematical Statistics with Applications
by Irwin Miller, Marylees Miller
Chapter: 5 Problem:20E
Copyright, 2010 Cramster, Inc.All Rights Reserved
www.Cramster.com
1
John E. Freund s Mathematical Statistics with Applications
by Irwin Mil
John E. Freund s Mathematical Statistics with Applications
by Irwin Miller, Marylees Miller
Chapter: 4 Problem:32E
Copyright, 2010 Cramster, Inc.All Rights Reserved
www.Cramster.com
1
Lecture 20
Nancy Pfenning Stats 1000
Standardized Statistics
Recall: If the underlying population variable X is normal with mean , standard deviation , then for a random sample of size n, the random variable X is normal with mean , standard deviation n .
Lecture 18
Nancy Pfenning Stats 1000
Chapter 9: Means and Proportions as Random Variables
Recall: in Section 1.3, we stated that the normal curve is idealized: its curve depicts an idealized histogram from a population with infinite possible values, all f
Lecture 17
Nancy Pfenning Stats 1000 In general, if we want to know the probability that any normal variable X falls in a given interval, we rewrite this as a problem about the standardized normal variable Z = X- , then use Table A.1, which gives the prob
Lecture 14
Nancy Pfenning Stats 1000
Chapter 7: Probability
Last time we established some basic definitions and rules of probability:
Rule 1:
P (AC ) = 1 - P (A).
Rule 2:
In general, the probability of one event or another occurring is P (A or B) = P (A)
Lecture 11
Nancy Pfenning Stats 1000
Chapter 6: Relationships Between Categorical Variables
Some variables are categorical by nature (eg. sex, race, major, political party); others are created by grouping quantitative variables into classes (eg. age as ch