Statistics II for Dummies

✍ Scribed by Rumsey, Deborah J

• Publisher: For Dummies
• Year: 2009
• Tongue: English
• Leaves: 413
• Series: For Dummies (Math & Science)
• Category: Library

✦ Synopsis

The ideal supplement and study guide for students preparing for advanced statisticsPacked with fresh and practical examples appropriate for a range of degree-seeking students,Statistics II For Dummieshelps any reader succeed in an upper-level statistics course. It picks up with data analysis whereStatistics For Dummiesleft off, featuring new and updated examples, real-world applications, and test-taking strategies for success. This easy-to-understand guide covers such key topics as sorting and testing models, using regression to make predictions, performing variance analysis (ANOVA), drawing test conclusions with chi-squares, and making comparisons with the Rank Sum Test.

✦ Table of Contents

Title Page......Page 3
Copyright Page......Page 4
Table of Contents......Page 9
About This Book......Page 17
Conventions Used in This Book......Page 18
How This Book Is Organized......Page 19
Part III: Analyzing Variance with ANOVA......Page 20
Icons Used in This Book......Page 21
Where to Go from Here......Page 22
Part I: Tackling Data Analysis and Model-Building Basics......Page 23
Data Analysis: Looking before You Crunch......Page 25
Data snooping isn’t cool......Page 27
No (data) fi shing allowed......Page 28
Population parameter......Page 29
Confidence interval......Page 30
Analysis of variance (ANOVA)......Page 31
Interaction effects......Page 32
Correlation......Page 33
Linear regression......Page 34
Chi-square tests......Page 35
Nonparametrics......Page 36
Chapter 2: Finding the Right Analysis for the Job ......Page 37
Categorical versus Quantitative Variables......Page 38
Estimating a proportion......Page 39
Comparing proportions......Page 40
Looking for relationships between categorical variables......Page 41
Building models to make predictions......Page 42
Making estimates......Page 43
Exploring relationships......Page 44
Predicting y using x......Page 46
Avoiding Bias......Page 47
Measuring Precision with Margin of Error......Page 49
Knowing Your Limitations......Page 50
Chapter 3: Reviewing Confidence Intervals and Hypothesis Tests......Page 53
Getting the basics: The general form of a confi dence interval......Page 54
Finding the confidence interval for a population mean......Page 55
What changes the margin of error?......Page 56
Interpreting a confidence interval......Page 59
What Ho and Ha really represent......Page 60
Determining strength of evidence with a p-value......Page 61
False alarms and missed opportunities: Type I and II errors......Page 62
The power of a hypothesis test......Page 64
Part II: Using Different Types of Regression to Make Predictions......Page 69
Chapter 4: Getting in Line with Simple Linear Regression......Page 71
Exploring Relationships with Scatterplots and Correlations......Page 72
Using scatterplots to explore relationships......Page 73
Collating the information by using the correlation coefficient......Page 74
Finding the best-fitting line to model your data......Page 76
The y-intercept of the regression line......Page 77
The slope of the regression line......Page 78
No Conclusion Left Behind: Tests and Confidence Intervals for Regression......Page 79
Scrutinizing the slope......Page 80
Inspecting the y-intercept......Page 82
Building confidence intervals for the average response......Page 84
Making the band with prediction intervals......Page 85
Defining the conditions......Page 87
Finding and exploring the residuals......Page 89
Using r2 to measure model fit......Page 92
Scoping for outliers......Page 93
Avoiding slipping into cause-and-effect mode......Page 95
Extrapolation: The ultimate no-no......Page 96
Sometimes you need more than one variable......Page 97
Getting to Know the Multiple Regression Model......Page 99
Looking at the general form of the multiple regression model......Page 100
Looking at x’s and y’s......Page 101
Collecting the Data......Page 102
Making scatterplots......Page 104
Correlations: Examining the bond......Page 105
Checking for Multicolinearity......Page 107
Finding the Best-Fitting Model for Two x Variables......Page 108
Getting the multiple regression coefficients......Page 109
Interpreting the coefficients......Page 110
Testing the coefficients......Page 111
Predicting y by Using the x Variables......Page 113
Plotting a plan to check the conditions......Page 114
Checking the three conditions......Page 116
Chapter 6: How Can I Miss You If You Won’t Leave? Regression Model Selection......Page 119
Brainstorming variables and collecting data......Page 120
Examining scatterplots and correlations......Page 122
Just Like Buying Shoes: The Model Looks Nice, But Does It Fit?......Page 125
Assessing the fi t of multiple regression models......Page 126
Model selection procedures......Page 127
Chapter 7: Getting Ahead of the Learning Curve with Nonlinear Regression......Page 131
Anticipating Nonlinear Regression......Page 132
Starting Out with Scatterplots......Page 133
Bringing back polynomials......Page 135
Searching for the best polynomial model......Page 138
Using a second-degree polynomial to pass the quiz......Page 139
Assessing the fit of a polynomial model......Page 142
Making predictions......Page 145
Recollecting exponential models......Page 146
Searching for the best exponential model......Page 147
Spreading secrets at an exponential rate......Page 149
Chapter 8: Yes, No, Maybe So: Making Predictions by Using Logistic Regression......Page 153
How is logistic regression different from other regressions?......Page 154
Using an S-curve to estimate probabilities......Page 155
Interpreting the coefficients of the logistic regression model......Page 156
The logistic regression model in action......Page 157
Running the analysis in Minitab......Page 158
Finding the coefficients and making the model......Page 160
Estimating p......Page 161
Checking the fit of the model......Page 162
Fitting the Movie Model......Page 163
Part III: Analyzing Variance with ANOVA......Page 167
Chapter 9: Testing Lots of Means? Come On Over to ANOVA!......Page 169
Comparing Two Means with a t-Test......Page 170
Spitting seeds: A situation just waiting for ANOVA......Page 171
Walking through the steps of ANOVA......Page 172
Checking the Conditions......Page 173
Looking for what’s normal......Page 174
Taking note of spread......Page 175
Doing the F-Test......Page 178
Running ANOVA in Minitab......Page 179
Breaking down the variance into sums of squares......Page 180
Locating those mean sums of squares......Page 181
Figuring the F-statistic......Page 182
Making conclusions from ANOVA......Page 184
What’s next?......Page 185
Checking the Fit of the ANOVA Model......Page 186
Chapter 10: Sorting Out the Means with Multiple Comparisons......Page 189
Comparing cellphone minutes: An example......Page 190
Setting the stage for multiple comparison procedures......Page 192
Pinpointing Differing Means with Fisher and Tukey......Page 193
Fishing for differences with Fisher’s LSD......Page 194
Using Fisher’s new and improved LSD......Page 195
Separating the turkeys with Tukey’s test......Page 198
Examining the Output to Determine the Analysis......Page 199
So Many Other Procedures, So Little Time!......Page 200
Controlling for baloney with the Bonferroni adjustment......Page 201
Finding out whodunit with Dunnett’s test......Page 202
Duncan’s multiple range test......Page 203
Going nonparametric with the Kruskal-Wallis test......Page 204
Chapter 11: Finding Your Way through Two-Way ANOVA ......Page 207
Determining the treatments......Page 208
Stepping through the sums of squares......Page 209
Understanding Interaction Effects......Page 210
Interacting with interaction plots......Page 211
Testing the Terms in Two-Way ANOVA......Page 214
Running the Two-Way ANOVA Table......Page 215
Interpreting the results: Numbers and graphs......Page 216
Are Whites Whiter in Hot Water? Two-Way ANOVA Investigates......Page 218
Chapter 12: Regression and ANOVA: Surprise Relatives!......Page 223
Spotting variability and fi nding an “x-planation”......Page 224
Getting results with regression......Page 225
Assessing the fit of the regression model......Page 227
Comparing sums of squares......Page 228
Dividing up the degrees of freedom......Page 230
Bringing regression to the ANOVA table......Page 231
Relating the F- and t-statistics: The fi nal frontier......Page 232
Part IV: Building Strong Connections with Chi-Square Tests......Page 235
Chapter 13: Forming Associations with Two-Way Tables......Page 237
Organizing data into a two-way table......Page 238
Filling in the cell counts......Page 239
Making marginal totals......Page 240
Breaking Down the Probabilities......Page 241
Marginal probabilities......Page 242
Joint probabilities......Page 243
Conditional probabilities......Page 244
Checking for independence between two categories......Page 249
Checking for independence between two variables......Page 251
Experiencing Simpson’s Paradox......Page 252
Figuring out why Simpson’s Paradox occurs......Page 255
Keeping one eye open for Simpson’s Paradox......Page 256
Chapter 14: Being Independent Enough for the Chi-Square Test ......Page 257
The Chi-square Test for Independence......Page 258
Collecting and organizing the data......Page 259
Figuring expected cell counts......Page 261
Checking the conditions for the test......Page 262
Calculating the Chi-square test statistic......Page 263
Finding your results on the Chi-square table......Page 265
Drawing your conclusions......Page 269
Putting the Chi-square to the test......Page 271
Getting reacquainted with the Z-test for two population proportions......Page 273
Equating Chi-square tests and Z-tests for a two-by-two table......Page 274
Chapter 15: Using Chi-Square Tests for Goodness-of-Fit (Your Data, Not Your Jeans).......Page 279
What’s observed versus what’s expected......Page 280
Calculating the goodness-of-fit statistic......Page 282
Interpreting the Goodness-of-Fit Statistic Using a Chi-Square......Page 284
The steps of the Chi-square goodness-of-fi t test......Page 286
Part V: Nonparametric Statistics: Rebels without a Distribution......Page 289
Arguing for Nonparametric Statistics......Page 291
No need to fret if conditions aren’t met......Page 292
The median’s in the spotlight for a change......Page 293
So, what’s the catch?......Page 295
Sign......Page 296
Rank......Page 298
Signed rank......Page 299
Rank sum......Page 300
Chapter 17: All Signs Point to the Sign Test and Signed Rank Test......Page 303
Reading the Signs: The Sign Test......Page 304
Testing the median......Page 306
Estimating the median......Page 308
Testing matched pairs......Page 310
A limitation of the sign test......Page 312
Stepping through the signed rank test......Page 313
Losing weight with signed ranks......Page 314
Checking the conditions......Page 319
Stepping through the test......Page 320
Stepping up the sample size......Page 322
Checking the conditions for this test......Page 323
Testing the hypotheses......Page 325
Doing the Kruskal-Wallis Test to Compare More than Two Populations......Page 329
Checking the conditions......Page 331
Conducting the test step by step......Page 333
Pairing off with pairwise comparisons......Page 336
Carrying out comparison tests to see who’s different......Page 337
Examining the medians to see how they’re different......Page 339
Chapter 20: Pointing Out Correlations with Spearman’s Rank......Page 341
Pickin’ On Pearson and His Precious Conditions......Page 342
Scoring with Spearman’s Rank Correlation......Page 343
Figuring Spearman’s rank correlation......Page 344
Watching Spearman at work: Relating aptitude to performance......Page 345
Part VI: The Part of Tens ......Page 349
Chapter 21: Ten Common Errors in Statistical Conclusions......Page 351
Chapter 22: Ten Ways to Get Ahead by Knowing Statistics......Page 363
Chapter 23: Ten Cool Jobs That Use Statistics ......Page 373
Appendix: Reference Tables ......Page 383
Index ......Page 395
EULA_Master.pdf......Page 0
EULA......Page 413

✦ Subjects

Science;Reference;Mathematics;Nonfiction;Business