Statistics Essentials For Dummies

• Introduction
  
• About This Book
  
• Conventions Used in This Book
  
• Foolish Assumptions
  
• Icons Used in This Book
  
• Chapter 1: Statistics in a Nutshell
  
• Designing Studies
  
• Surveys
  
• Experiments
  
• Collecting Data
  
• Selecting a good sample
  
• Avoiding bias in your data
  
• Describing Data
  
• Descriptive statistics
  
• Charts and graphs
  
• Analyzing Data
  
• Making Conclusions
  
• Chapter 2: Descriptive Statistics
  
• Types of Data
  
• Counts and Percents
  
• Measures of Center
  
• Measures of Variability
  
• Percentiles
  
• Finding a percentile
  
• Interpreting percentiles
  
• The Five-Number Summary
  
• Chapter 3: Charts and Graphs
  
• Pie Charts
  
• Bar Graphs
  
• Time Charts
  
• Histograms
  
• Making a histogram
  
• Interpreting a histogram
  
• Evaluating a histogram
  
• Boxplots
  
• Making a boxplot
  
• Interpreting a boxplot
  
• Chapter 4: The Binomial Distribution
  
• Characteristics of a Binomial
  
• Checking the binomial conditions step by step
  
• Non-binomial examples
  
• Finding Binomial Probabilities Using the Formula
  
• Finding Probabilities Using the Binomial Table
  
• Finding probabilities when p 0.50
  
• Finding probabilities when p > 0.50
  
• Finding probabilities for X greater-than, less-than, or between two values
  
• The Expected Value and Variance of the Binomial
  
• Chapter 5: The Normal Distribution
  
• Basics of the Normal Distribution
  
• The Standard Normal (Z) Distribution
  
• Finding Probabilities for X
  
• Finding X for a Given Probability
  
• Normal Approximation to the Binomial
  
• Chapter 6: Sampling Distributions and the Central Limit Theorem
  
• Sampling Distributions
  
• The mean of a sampling distribution
  
• Standard error of a sampling distribution
  
• Sample size and standard error
  
• Population standard deviation and standard error
  
• The shape
  
• Finding Probabilities for
  
• The Sampling Distribution of the Sample Proportion
  
• What proportion of students need math help?
  
• Finding Probabilities for
  
• Chapter 7: Confidence Intervals
  
• Making Your Best Guesstimate
  
• The Goal: Small Margin of Error
  
• Choosing a Confidence Level
  
• Factoring In the Sample Size
  
• Counting On Population Variability
  
• Confidence Interval for a Population Mean
  
• Confidence Interval for a Population Proportion
  
• Confidence Interval for the Difference of Two Means
  
• Confidence Interval for the Difference of Two Proportions
  
• Interpreting Confidence Intervals
  
• Spotting Misleading Confidence Intervals
  
• Chapter 8: Hypothesis Tests
  
• Doing a Hypothesis Test
  
• Identifying what you're testing
  
• Setting up the hypotheses
  
• Finding sample statistics
  
• Standardizing the evidence: the test statistic
  
• Weighing the evidence and making decisions: p-values
  
• General steps for a hypothesis test
  
• Testing One Population Mean
  
• Testing One Population Proportion
  
• Comparing Two Population Means
  
• Testing the Mean Difference: Paired Data
  
• Testing Two Population Proportions
  
• You Could Be Wrong: Errors in Hypothesis Testing
  
• A false alarm: Type-1 error
  
• A missed detection: Type-2 error
  
• Chapter 9: The t-distribution
  
• Basics of the t-Distribution
  
• Understanding the t-Table
  
• t-distributions and Hypothesis Tests
  
• Finding critical values
  
• Finding p-values
  
• t-distributions and Confidence Intervals
  
• Chapter 10: Correlation and Regression
  
• Picturing the Relationship with a Scatterplot
  
• Making a scatterplot
  
• Interpreting a scatterplot
  
• Measuring Relationships Using the Correlation
  
• Calculating the correlation
  
• Interpreting the correlation
  
• Properties of the correlation
  
• Finding the Regression Line
  
• Which is X and which is Y?
  
• Checking the conditions
  
• Understanding the equation
  
• Finding the slope
  
• Finding the y-intercept
  
• Interpreting the slope and y-intercept
  
• Making Predictions
  
• Avoid Extrapolation!
  
• Correlation Doesn't Necessarily Mean Cause-and-Effect
  
• Chapter 11: Two-Way Tables
  
• Organizing and Interpreting a Two-way Table
  
• Defining the outcomes
  
• Setting up the rows and columns
  
• Inserting the numbers
  
• Finding the row, column, and grand totals
  
• Finding Probabilities within a Two-Way Table
  
• Figuring joint probabilities
  
• Calculating marginal probabilities
  
• Finding conditional probabilities
  
• Checking for Independence
  
• Chapter 12: A Checklist for Samples and Surveys
  
• The Target Population Is Well Defined
  
• The Sample Matches the Target Population
  
• The Sample Is Randomly Selected
  
• The Sample Size Is Large Enough
  
• Nonresponse Is Minimized
  
• The importance of following up
  
• Anonymity versus confidentiality
  
• The Survey Is of the Right Type
  
• Questions Are Well Worded
  
• The Timing Is Appropriate
  
• Personnel Are Well Trained
  
• Proper Conclusions Are Made
  
• Chapter 13: A Checklist for Judging Experiments
  
• Experiments versus Observational Studies
  
• Criteria for a Good Experiment
  
• Inspect the Sample Size
  
• Small samples — small conclusions
  
• Original versus final sample size
  
• Examine the Subjects
  
• Check for Random Assignments
  
• Gauge the Placebo Effect
  
• Identify Confounding Variables
  
• Assess Data Quality
  
• Check Out the Analysis
  
• Scrutinize the Conclusions
  
• Overstated results
  
• Ad-hoc explanations
  
• Generalizing beyond the scope
  
• Chapter 14: Ten Common Statistical Mistakes
  
• Misleading Graphs
  
• Pie charts
  
• Bar graphs
  
• Time charts
  
• Histograms
  
• Biased Data
  
• No Margin of Error
  
• Nonrandom Samples
  
• Missing Sample Sizes
  
• Misinterpreted Correlations
  
• Confounding Variables
  
• Botched Numbers
  
• Selectively Reporting Results
  
• The Almighty Anecdote
  
• Appendix: Tables for Reference
  

Statistics Essentials For Dummies
^®

by Deborah Rumsey, PhD

Statistics Essentials For Dummies
^®

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