Understandable Statistics: Concepts and Methods 9th edition

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Charles Henry Brase and Corinne Pellillo Brase
Publisher: Cengage Learning

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  • Chapter 1: Getting Started
    • 1.1: What Is Statistics (16)
    • 1.2: Random Samples (10)
    • 1.3: Introduction to Experimental Design (7)
    • 1: Chapter Review (8)

  • Chapter 2: Organizing Data
    • 2.1: Frequency Distributions, Histograms, and Related Topics (17)
    • 2.2: Bar Graphs, Circle Graphs, and Time-Series Graphs (10)
    • 2.3: Stem-and-Leaf Displays (10)
    • 2: Chapter Review (10)

  • Chapter 3: Averages and Variation
    • 3.1: Measures of Central Tendency: Mode, Median, and Mean (18)
    • 3.2: Measures of Variation (21)
    • 3.3: Percentiles and Box-and-Whisker Plots (10)
    • 3: Chapter Review (11)

  • Chapter 4: Elementary Probability Theory
    • 4.1: What Is Probability (15)
    • 4.2: Some Probability Rules-Compound Events (28)
    • 4.3: Trees and Counting Techniques (27)
    • 4: Chapter Review (16)

  • Chapter 5: The Binomial Probability Distribution and Related Topics
    • 5.1: Introduction to Random Variables and Probability Distributions (17)
    • 5.2: Binomial Probabilities (24)
    • 5.3: Additional Properties of the Binomial Distribution (24)
    • 5.4: The Geometric and Poisson Probability Distributions (32)
    • 5: Chapter Review (20)

  • Chapter 6: Normal Distributions
    • 6.1: Graphs of Normal Probability Distributions (16)
    • 6.2: Standard Units and Areas Under the Standard Normal Distribution (49)
    • 6.3: Areas Under Any Normal Curve (40)
    • 6.4: Normal Approximation to the Binomial Distribution (14)
    • 6: Chapter Review (25)

  • Chapter 7: Introduction to Sampling Distributions
    • 7.1: Sampling Distributions (9)
    • 7.2: The Central Limit Theorem (21)
    • 7.3: Sampling Distributions for Proportions (13)
    • 7: Chapter Review (9)

  • Chapter 8: Estimation
    • 8.1: Estimating µ When σ Is Known (21)
    • 8.2: Estimating µ When σ Is Unknown (21)
    • 8.3: Estimating p in the Binomial Distribution (21)
    • 8.4: Estimating µ1 - µ2 and p1 - p2 (23)
    • 8: Chapter Review (19)

  • Chapter 9: Hypothesis Testing
    • 9.1: Introduction to Statistical Tests (14)
    • 9.2: Testing the Mean (30)
    • 9.3: Testing a Proportion p (22)
    • 9.4: Tests Involving Paired Differences ( Dependent Samples) (22)
    • 9.5: Testing µ1 - µ2 and p1 - p2 (Independent Samples) (32)
    • 9: Chapter Review (18)

  • Chapter 10: Correlation and Regression
    • 10.1: Scatter Diagrams and Linear Correlation (22)
    • 10.2: Linear Regression and the Coefficient of Determination (25)
    • 10.3: Inferences for Correlation and Regression (14)
    • 10.4: Multiple Regression (7)
    • 10: Chapter Review (10)

  • Chapter 11: Chi-Square and F Distributions
    • 11.1: Chi-Square: Tests of Independence and of Homogeneity (15)
    • 11.2: Chi-Square: Goodness of Fit (18)
    • 11.3: Testing and Estimating a Single Variance or Standard Deviation (11)
    • 11.4: Testing Two Variances (12)
    • 11.5: One-Way ANOVA: Comparing Several Sample Means (9)
    • 11.6: Introduction to Two-Way ANOVA (7)
    • 11: Chapter Review (14)

  • Chapter 12: Nonparametric Statistics
    • 12.1: The Sign Test for Matched Pairs (14)
    • 12.2: Test Rank-Sum Test (12)
    • 12.3: Spearman Rank Correlation (13)
    • 12.4: Runs Test for Randomness (14)
    • 12: Chapter Review (10)

Questions Available within WebAssign

Most questions from this textbook are available in WebAssign. The online questions are identical to the textbook questions except for minor wording changes necessary for Web use. Whenever possible, variables, numbers, or words have been randomized so that each student receives a unique version of the question. This list is updated nightly.

Question Group Key
R - Chapter Review Problems


Question Availability Color Key
BLACK questions are available now
GRAY questions are under development


Group Quantity Questions
Chapter 1: Getting Started
1.R 8 001 002 003 004 005 006 007 009
1.1 16 001 002 003 004 005 006 007.MI 007.MI.SA 008 009.MI 009.MI.SA 010.MI 010.MI.SA 011 012 013
1.2 10 001 002 003 004 005 006 011 012 015 016
1.3 7 001 002 003 004 005 006 007
Chapter 2: Organizing Data
2.R 10 001 002 003 004 005 006 008 009 010 011
2.1 17 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017
2.2 10 001 002 003 005 006.MI 006.MI.SA 008 009 010 012
2.3 10 001 002 003 004 005 006 007 008 009 010
Chapter 3: Averages and Variation
3.R 11 001 002 003 004 005 006 007 008 009 010 011
3.1 18 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018
3.2 21 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021
3.3 10 001 002 003 004 005 006 007 008 009 010
Chapter 4: Elementary Probability Theory
4.R 16 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016
4.1 15 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015
4.2 28 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027 028
4.3 27 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027
Chapter 5: The Binomial Probability Distribution and Related Topics
5.R 20 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020
5.1 17 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017
5.2 24 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024
5.3 24 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024
5.4 32 001 002 003 004 005 006 007.MI 007.MI.SA 008 009 010.MI 010.MI.SA 011 012 013 014 015.MI 015.MI.SA 016 017 018 019 020 021 022 023 024 025 026 027 028 029
Chapter 6: Normal Distributions
6.R 25 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025
6.1 16 001 002 003 004 005 006 007 008 009 010.MI 010.MI.SA 011 012 013 014 015
6.2 49 001 002 003 004 005 006 007.MI 007.MI.SA 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027 028 029 030 031 032 033 034 035 036 037 038 039 040 041 042 043 044 045 046 047 048
6.3 40 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027 028 029 030 031 032 033 034 035 036 037 038 039 040
6.4 14 001 002 003 004 005 006 007 008 009 010 011 012 013 014
Chapter 7: Introduction to Sampling Distributions
7.R 9 001 002 003 004 005 006 007 008 009
7.1 9 001 002 003 004 005 006 007 008 009
7.2 21 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021
7.3 13 001 002 003 004 005 006 007 008 009 010 011 012 013
Chapter 8: Estimation
8.R 19 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019
8.1 21 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021
8.2 21 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021
8.3 21 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021
8.4 23 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023
Chapter 9: Hypothesis Testing
9.R 18 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018
9.1 14 001 002 003 004 005 006 007 008 009 010 011 012 013 014
9.2 30 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027 028 029 030
9.3 22 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022
9.4 22 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022
9.5 32 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027 028 029 030 031 032
Chapter 10: Correlation and Regression
10.R 10 001 002 003 004 005 006 007 008 009 010
10.1 22 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022
10.2 25 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025
10.3 14 001 002 003 004 005 006 007 008 009 010 011 012 013 014
10.4 7 001 002.MI 002.MI.SA 003 004 005 006
Chapter 11: Chi-Square and F Distributions
11.R 14 001 002 003 004 005 006 007 008 009 010 011 012 013 014
11.1 15 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015
11.2 18 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018
11.3 11 001 002 003 004 005 006 007 008 009 010 011
11.4 12 001 002 003 004 005 006 007 008 009 010 011 012
11.5 9 001 002 003 004 005 006 007 008 009
11.6 7 001 002 003 004 005 006 007
Chapter 12: Nonparametric Statistics
12.R 10 001 002 003 004 005 006 007 008 009 010
12.1 14 001 002 003.MI 003.MI.SA 004 005 006.MI 006.MI.SA 007 008 009 010 011 012
12.2 12 001 002 003.MI 003.MI.SA 004 005 006 007 008 009 010 011
12.3 13 001 002 003.MI 003.MI.SA 004 005 006 007.MI 007.MI.SA 008 009 010 011
12.4 14 001 002 003.MI 003.MI.SA 004 005 006 007.MI 007.MI.SA 008 009 010 011 012
Total 1017