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Introduction | |

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Why Study Statistics? | |

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What Is Statistics? | |

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More About Inferential Statistics | |

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Three Types of Data | |

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Levels of Measurement | |

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Types of Variables | |

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How to Use This Book | |

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Summary | |

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Important Terms | |

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Review Questions | |

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Descriptive Statistics | |

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Describing Data with Tables and Graphs | |

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Tables Frequency Distributions | |

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Frequency Distributions for Quantitative Data | |

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Guidelines | |

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Outliers | |

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Relative Frequency Distributions | |

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Cumulative Frequency Distributions | |

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Frequency Distributions for Qualitative (Nominal) Data | |

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Interpreting Distributions Constructed by Others | |

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Graphs | |

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Graphs for Quantitative Data | |

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Typical Shapes | |

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A Graph for Qualitative (Nominal) Data | |

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Misleading Graphs | |

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Doing It Yourself | |

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Summary | |

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Important Terms | |

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Review Questions | |

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Describing Data with Averages | |

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Mode | |

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Median | |

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Mean | |

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Which Average? | |

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Averages for Qualitative and Ranked Data | |

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Summary. Important Terms | |

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Key Equation | |

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Review Questions | |

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Describing Variability | |

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Intuitive Approach | |

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Range | |

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Variance | |

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Standard Deviation | |

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DETAILS: Standard Deviation | |

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Degrees of Freedom (df | |

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Interquartile Range (IQR | |

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Measures of Variability for Qualitative and Ranked Data | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Normal Distributions and Standard Scores (z) | |

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The Normal Curve | |

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z Scores | |

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Standard Normal Curve | |

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Solving Normal Curve Problems | |

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Finding Proportions | |

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Finding Scores | |

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More about z Scores | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Describing Relationships: Correlation | |

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An Intuitive Approach | |

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Scatterplots | |

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A Correlation Coefficient for Quantitative Data: r | |

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DETAILS: z Score Formula for r | |

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DETAILS: Computation Formula for r | |

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Outliers Again | |

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Other Types of Correlation Coefficients | |

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Computer Output | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Regression | |

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Two Rough Predictions | |

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A Regression Line | |

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Least Squares Regression Line | |

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Standard Error of Estimate, S<sub>yï¿½x</sub> | |

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Assumptions | |

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Multiple Regression Equations | |

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Regression Toward The Mean | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Inferential Statistics | |

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Populations, Samples, and Probability | |

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Populations and Samples | |

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Populations | |

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Samples | |

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Random Sampling | |

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Tables of Random Numbers | |

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Random Assignment of Subjects | |

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Surveys or Experiments? | |

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Probability | |

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Definition | |

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Addition Rule | |

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Multiplication Rule | |

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Probability and Statistics | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Sampling Distribution of the Mean | |

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What is a Sampling Distribution? | |

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Creating a Sampling Distribution from Scratch | |

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Some Important Symbols | |

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Mean of All Sample Means | |

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Standard Error of the Means | |

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Shape of the Sampling Distribution | |

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Other Sampling Distributions | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Introduction to Hypothesis Testing: the z Test | |

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Testing a Hypothesis about SAT Scores | |

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z Test for a Population Mean | |

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Step-by-Step Procedure | |

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Statement of the Research Problem | |

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Null Hypothesis (H<sub>0</sub> | |

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Alternative Hypothesis (H<sub>1</sub> | |

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Decision Rule | |

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Calculations | |

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Decision | |

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Interpretation | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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More about Hypothesis Testing | |

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Why Hypothesis Tests? | |

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Strong or Weak Decisions | |

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One-Tailed and Two-Tailed Tests | |

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Choosing a Level of Significance (a) | |

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Testing a Hypothesis about Vitamin C | |

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Four Possible Outcomes | |

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If H<sub>0</sub> Really Is True | |

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If H<sub>0</sub> Really Is False Because of a Large Effect | |

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If H<sub>0</sub> Really Is False Because of a Small Effect | |

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Influence of Sample Size | |

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Power and Sample Size | |

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Summary | |

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Important Terms | |

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Review Questions | |

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Estimation Confidence Intervals | |

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Point Estimate for m | |

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Confidence Interval (CI) for m | |

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Interpretation of a Confidence Interval | |

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Level of Confidence | |

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Effect of Sample Size | |

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Hypothesis Tests or Confidence Intervals? | |

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Confidence Interval for Population Percent | |

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Summary | |

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Important Terms | |

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Key Equation | |

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Review Questions | |

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tTest for One Sample | |

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Gas Mileage Investigation | |

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Sampling Distribution of t | |

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t Test | |

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Common Theme of Hypothesis Tests | |

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Reminder about Degrees of Freedom | |

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Details: Estimating the Standard Error | |

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Details: Calculations for t Test | |

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Confidence Intervals for m Based on t | |

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Assumptions | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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t Test for Two Independent Samples | |

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EPO Experiment | |

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Statistical Hypotheses | |

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Sampling Distribution | |

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t Test | |

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DETAILS: Calculations for t Test | |

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p-Values | |

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Statistically Significant Results | |

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Estimating Effect Size: Point Estimates and Confidence Intervals | |

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Estimating Effect Size: Cohen's d | |

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Reports in the Literature | |

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Assumptions | |

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Computer Output | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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t Test for Two Related Samples Repeated Measures | |

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EPO Experiment with Repeated Measures | |

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Statistical Hypotheses | |

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Sampling Distribution | |

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t Test | |

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DETAILS: Calculations for t Test | |

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Estimating Effect Size | |

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Assumptions | |

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Overview: Three t Tests for Population Means | |

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t Test for the Population Correlation Coefficient, | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Analysis of Variance One Factor | |

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Testing a Hypothesis about Aggression and Sleep Deprivation | |

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Two Sources of Variability | |

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F Test | |

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Details: Variance Estimates | |

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Details: Mean Squares (MS) and the F Ratio | |

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Table for F Distribution | |

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ANOVA Summary Tables | |

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F Test Is Nondirectional | |

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Estimating Effect Size | |

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Multiple Comparisons | |

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Overview: Flow Chart for ANOVA | |

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Reports in the Literature | |

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Assumptions | |

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Computer Output | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Analysis of Variance Repeated Measures | |

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Sleep Deprivation Experiment with Repeated Measures | |

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F Test | |

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Two Complications | |

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Details: Variance Estimates | |

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Details: Mean Square (MS) and the F Ratio | |

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Table for F Distribution | |

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ANOVA Summary Tables | |

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Estimating Effect Size | |

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Multiple Comparisons | |

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Reports in the Literature | |

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Assumptions | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Analysis of Variance Two Factors | |

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A Two-Factor Experiment: Responsibility in Crowds | |

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Three F Tests | |

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Interaction | |

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DETAILS: Variance Estimates | |

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DETAILS: Mean Squares (MS) and F Ratios | |

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Table for F Distribution | |

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Estimating Effect Size | |

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Multiple Comparisons | |

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Simple Effects | |

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Overview: Flow Chart for Two-Factor ANOVA | |

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Reports in the Literature | |

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Assumptions | |

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Other Types of ANOVA | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Chi-Square (cï¿½) Test for Qualitative (Nominal) Data | |

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One-variable cï¿½ Test | |

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Survey of Blood Types | |

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Statistical Hypotheses | |

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DETAILS: Calculation of cï¿½ | |

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Table for cï¿½ Distribution | |

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cï¿½ Test | |

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Two-variable cï¿½ Test | |

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Lost Letter Study | |

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Statistical Hypotheses | |

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Details: Calculation ofcï¿½ | |

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Table for cï¿½ Distribution | |

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cï¿½ Test | |

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Estimating Effect Size | |

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Odds Ratios | |

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Reports in the Literature | |

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Some Precautions | |

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Computer Output | |

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Summary | |

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Important Terms | |

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Key Equations | |

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Review Questions | |

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Tests for Ranked (Ordinal) Data | |

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Use Only When Appropriate | |

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A Note on Terminology | |

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Mann-Whitney U Test | |

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Wilcoxon T Test Two Related Samples | |

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Kruskal-Wallis H Test Three or More Independent Samples | |

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General Comment: Ties | |

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Summary | |

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Important Terms | |

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Review Questions | |

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Postscript: Which Test? | |

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Descriptive or Inferential Statistics? | |

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Hypothesis Tests or Confidence Intervals? | |

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Quantitative or Qualitative Data? | |

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Distinguishing between the Two Types of Data | |

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One, Two, or More Groups? | |

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Concluding Comments | |

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Review Questions | |

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Appendices | |

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Math Review | |

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Answers to Selected Questions | |

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Tables | |

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Glossary | |

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Index | |