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Preface | |

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Why the Criminal Justice Researcher Uses Statistics | |

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The Nature of Criminal Justice Research | |

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The Experiment | |

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The Quasi-Experiment | |

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The Survey | |

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Meta-Analysis | |

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Other Methods | |

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Major Data Sources in Criminology and Criminal Justice | |

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Surveys | |

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Police Reports | |

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Why Test Hypotheses? | |

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The Stages of Criminal Justice Research | |

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Using Series of Numbers to Do Criminal Justice Research | |

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The Nominal Level | |

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The Ordinal Level | |

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The Interval (and Ratio) Level | |

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Treating Ordinal Data as Interval | |

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Further Measurement Issues | |

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Functions of Statistics | |

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Description | |

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Decision Making | |

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An Important Note about Rounding | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Looking at the Larger Picture: A Student Survey | |

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Description | |

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Organizing the Data | |

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Frequency Distributions of Nominal Data | |

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Comparing Distributions | |

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Proportions and Percentages | |

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Rates | |

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Simple Frequency Distributions of Ordinal and Interval Data | |

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Grouped Frequency Distributions of Interval Data | |

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The Midpoint | |

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Guidelines for Constructing Class Intervals | |

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Cumulative Distributions | |

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Dealing with Decimal Data | |

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Flexible Class Intervals | |

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Cross-Tabulations | |

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Graphic Presentations | |

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Pie Charts | |

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Bar Graphs and Histograms | |

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Frequency Polygons | |

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The Shape of a Frequency Distribution | |

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Line Chart | |

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Maps | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Measures of Central Tendency | |

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The Mode | |

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The Median | |

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The Mean | |

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Taking One Step at a Time | |

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Obtaining the Mode, Median, and Mean from a Simple Frequency Distribution | |

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Comparing the Mode, Median, and Mean | |

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Level of Measurement | |

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Shape of the Distribution | |

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Research Objective | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Measures of Variability | |

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The Range | |

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The Variance and the Standard Deviation | |

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The Raw-Score Formula for Variance and Standard Deviation | |

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Obtaining the Variance and Standard Deviation from a Simple Frequency Distribution | |

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Coefficient of Variation | |

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The Meaning of the Standard Deviation | |

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Comparing Measures of Variability | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Looking at the Larger Picture: Describing Data | |

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From Description to Decision Making | |

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Probability and the Normal Curve | |

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Rules of Probability | |

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Probability Distributions | |

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The Difference between Probability Distributions and Frequency Distributions | |

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Mean and Standard Deviation of a Probability Distribution | |

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The Normal Curve as a Probability Distribution | |

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Characteristics of the Normal Curve | |

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The Model and the Reality of the Normal Curve | |

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The Area under the Normal Curve | |

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Clarifying the Standard Deviation | |

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Using Table A | |

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Standard Scores and the Normal Curve | |

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Finding Probability under the Normal Curve | |

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Finding Scores from Probability Based on the Normal Curve | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Samples and Populations | |

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Errors in the Conduct of Research | |

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Sampling Methods | |

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Sampling Error | |

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Sampling Distribution of Means | |

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Characteristics of a Sampling Distribution of Means | |

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The Sampling Distribution of Means as a Normal Curve | |

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Standard Error of the Mean | |

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Confidence Intervals | |

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The t Distribution | |

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Estimating Proportions | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Looking at the Larger Picture: Generalizing from Samples to Populations | |

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Decision Making | |

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Testing Differences Between Means | |

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Testing the Difference between Sample and Population Means | |

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Testing the Difference between Two Sample Means | |

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The Null Hypothesis: No Difference between Means | |

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The Research Hypothesis: A Difference between Means | |

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Sampling Distribution of Differences between Means | |

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Testing Hypotheses with the Distribution of Differences between Means | |

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Levels of Significance | |

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Choosing a Level of Significance | |

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What Is the Difference between P and ï¿½? | |

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Standard Error of the Difference between Means | |

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Testing the Difference between Means | |

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Comparing Dependent Samples | |

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Two Sample Test of Proportions | |

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One-Tailed Tests | |

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Requirements for Testing the Difference between Means | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Analysis of Variance | |

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The Logic of Analysis of Variance | |

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The Sum of Squares | |

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A Research illustration | |

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Computing Sums of Squares | |

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Mean Square | |

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The F Ratio | |

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A Multiple Comparison of Means | |

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Requirements for Using the F Ratio | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Nonparametric Tests of Significance | |

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One-Way Chi-Square Test | |

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Two-Way Chi-Square Test | |

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Finding the Expected Frequencies | |

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Comparing Several Groups | |

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Correcting for Small Expected Frequencies | |

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Requirements for the Use of Two-Way Chi-Square | |

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The Median Test | |

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Requirements for the Use of the Median Test | |

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Mann-Whitney U Test | |

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Requirements for the Use of the Mann-Whitney U Test | |

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Kruskal-Wallis Test | |

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Requirements for the Use of the Kruskal-Wallis Test | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Looking at the Larger Picture: Testing for Differences | |

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From Decision Making to Association | |

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Correlation | |

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Strength of Correlation | |

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Direction of Correlation | |

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Curvilinear Correlation | |

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The Correlation Coefficient | |

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Pearson's Correlation Coefficient | |

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A Computational Formula for Pearson's r | |

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Testing the Significance of Pearson's r | |

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A Simplified Method for Testing the Significance of r | |

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Requirements for the Use of Pearson's Correlation Coefficient | |

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The Importance of Scatter Plots | |

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Partial Correlation | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Regression Analysis | |

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The Regression Model | |

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Requirements for Regression | |

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Interpreting the Regression Line | |

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Prediction Errors | |

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The Least Squares Criterion | |

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Regression and Pearson's Correlation | |

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Regression and Analysis of Variance | |

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Multiple Regression* | |

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Dummy Variables | |

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Interaction Terms | |

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Multicollinearity | |

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Logistic Regression | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Nonparametric Measures of Correlation | |

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Spearman's Rank-Order Correlation Coefficient | |

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Dealing with Tied Ranks | |

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Testing the Significance of the Rank-Order Correlation Coefficient | |

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Requirements for Using the Rank-Order Correlation Coefficient | |

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Goodman's and Kruskal's Gamma | |

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Testing the Significance of Gamma | |

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Requirements for Using Gamma | |

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Correlation Coefficient for Nominal Data Arranged in a 2 ï¿½ 2 Table | |

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Testing the Significance of Phi | |

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Requirements for Using the Phi Coefficient | |

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Correlation Coefficients for Nominal Data in Larger than 2 ï¿½ 2 Tables | |

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Testing the Significance of the Contingency Coefficient | |

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Requirements for Using the Contingency Coefficient | |

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An Alternative to the Contingency Coefficient | |

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Summary | |

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Questions and Problems | |

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Computer Exercises | |

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Looking at the Larger Picture: Measuring Association | |

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Applying Statistics | |

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Applying Statistical Procedures to Research Problems | |

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Research Situations | |

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Research Solutions | |

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Using SPSS and the General Social Survey | |

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StatCrunch™ Data Analysis on the Web | |

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Tables | |

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A Review of Some Fundamentals of Mathematics | |

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List of Formulas | |

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Glossary | |

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Solutions to Problems | |

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Index | |