David Freedman, Robert Pisani, Roger Purves
ISBN #9780393929720
4th Edition
314 Questions
Homework Questions
Statistics is a comprehensive exploration of statistical methods and concepts, beginning with the design of controlled experiments and observational studies that minimize bias and confounding factors. The book methodically introduces key analytical tools—from graphical representations like histograms and scatter diagrams to measures of central tendency and variability, such as averages and standard deviations. It then builds on these foundations with in-depth discussions on probability, regression analysis, and various tests of significance, applying these techniques to real-world examples like the Salk vaccine trial and Mendel’s genetic experiments. Overall, the text serves as a practical guide for navigating the complexities of data interpretation, prediction, and inference across diverse fields.
Chapter 2
Observational Studies
Chapter 3
The Histogram
Chapter 4
The Average and the Standard Deviation
Chapter 5
The Normal Approximation for Data
Chapter 6
Measurement Error
Chapter 8
Correlation
Chapter 9
More about Correlation
Chapter 10
Regression
Chapter 11
The R.M.S. Error for Regression
Chapter 12
The Regression Line
Chapter 13
What Are the Chances?
Chapter 14
More about Chance
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Chapter 15
The Binomial Formula
Chapter 16
The Law of Averages
Chapter 17
The Expected Value and Standard Error
Chapter 18
The Normal Approximation for Probability Histograms
Chapter 19
Sample Surveys
Chapter 20
Chance Errors in Sampling
Chapter 21
The Accuracy of Percentages
Chapter 22
Measuring Employment and Unemployment
Chapter 23
The Accuracy of Averages
Chapter 24
A Model for Measurement Error
Chapter 25
Chance Models in Genetics
Chapter 26
Tests of Significance
Chapter 27
More Tests for Averages
Chapter 28
The Chi-Square Test
Chapter 29
A Closer Look at Tests of Significance
Problem 1
Four hundred draws will be made at random with replacement from the box $|[1][3][5][7]|$ (a) Estimate the chance that the sum of the draws will be more than $1,500 .$ (b) Estimate the chance that there will be fewer than 90$[3]$ 's.
Wendi Obritz Numerade Educator
Problem 2
The following list of test scores has an average of 50 and an $S D$ of $10 :$ $\begin{array}{lllllllllll}{39} & {41} & {47} & {58} & {65} & {37} & {37} & {49} & {56} & {59} & {62} & {36} & {48} \\ {52} & {64} & {29} & {44} & {47} & {49} & {52} & {53} & {54} & {72} & {50} & {50}\end{array}$ $\begin{array}{l}{\text { (a) Use the normal approximation to estimate the number of scores within }} \\ {1.25 \text { SDs of the average. }} \\ {\text { (b) How many scores really were within } 1.25 \text { SDs of the average? }}\end{array}$
Bryan Luo Numerade Educator
Problem 3
A box contains $10,000$ tickets: $4,000[0]$ 's and $6,000[11$ 's. And $10,000$ draws will be made at random with replacement from this box. Which of the following best describes the situation, and why? (i) The number of 1 's will be $6,000$ exactly. (ii) The number of $1^{\text { 's }}$ is very likely to equal $6,000,$ but there is also some small chance that it will not be equal to $6,000 .$ (iii) The number of $1^{\prime}$ 's is likely to be different from $6,000,$ but the difference is likely to be small compared to $10,000 .$
Problem 4
As part of a study on the selection of grand juries in Alameda county, the ed- ucational level of grand jurors was compared with the county distribution: Could a simple random sample of 62 people from the county show a distribu- tion of educational level so different from the county-wide one? Choose one option and explain. $$ \begin{array}{l}{\text { (i) This is absolutely impossible. }} \\ {\text { (ii) This is possible, but fantastically unlikely. }} \\ {\text { (iv) This is qossible but unlikely-the chance is around } 1 \% \text { or so. }} \\ {\text { (iv) This is quite possible-the chance is around } 10 \% \text { or so. }} \\ {\text { (v) This is nearly certain. }}\end{array} $$
Heena Haldankar Numerade Educator
Problem 5
One hundred draws will be made at random with replacement from the box (a) How small can the sum of the draws be? How large? (b) The sum is between 650 and 750 with a chance of about 1$\% \quad 10 \% \quad 50 \% \quad 90 \% \quad 99 \%$
Problem 6
The age distribution of people in the U.S. in 2004 is shown below. Draw the histogram. (The class intervals include the left endpoint, not the right; for in- stance, on the second line of the table, 14$\%$ of the people were age 5 years or more but had not yet turned $15 .$ The interval for 475 and over" can be ended at $85 .$ Men and women are combined in the data.) Use your histogram to answer the following questions. $$\begin{array}{l}{\text { (a) Are there more children age } 1, \text { or elders age } 71 ?} \\ {\text { (b) Are there more } 21-\text { year-olds, or } 61-\text { year-olds? }} \\ {\text { (c) Are there more people age } 0-4, \text { or } 65-69 \text { ? }} \\ {\text { (d) The percentage of people age } 35 \text { and over is around } 25 \%, 50 \%, \text { or } 75 \% ?}\end{array}$$
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