Page 21 - Intermediate Statistics for Dummies

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Intermediate Statistics For Dummies
Chapter 20: Pointing Out Correlations with Spearman’s Rank . . . . .307
Pickin’ On Pearson and His Precious Conditions ....................................308
Scoring with Spearman’s Rank Correlation ..............................................309
Figuring Spearman’s rank correlation..............................................310
Watching Spearman at work: Relating aptitude to
performance ....................................................................................311
Part VI: The Part of Tens............................................315
Chapter 21: Ten Errors in Statistical Conclusions . . . . . . . . . . . . . . . .317
These Statistics Prove . . . ...........................................................................317
It’s Not Technically Statistically Significant, But . . .................................318
This Means X Causes Y ...............................................................................318
I Assumed the Data Was Normal . . ...........................................................319
I’m Only Reporting “Important” Results ...................................................320
A Bigger Sample Is Always Better .............................................................321
It’s Not Technically Random, But . . ..........................................................322
1,000 Responses Is 1,000 Responses .........................................................323
Of Course These Results Apply to the General Population!...................324
I Just Decided to Leave It Out.....................................................................325
Chapter 22: Ten Practice Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . .327
Comparing Means with One-Way ANOVA..................................................327
Doing Multiple Comparisons ......................................................................328
Looking at Two Factors with Two-Way ANOVA........................................330
Predicting a Quantitative Variable by Using Regression.........................331
Predicting a Probability with Logistic Regression...................................332
Using Nonlinear Regression for Curved Data...........................................333
Using Chi-Square to Test for Independence .............................................335
Checking Specific Models with the Goodness-of-Fit Test .......................336
Estimating the Median with the Signed Rank Test...................................336
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Checking Model Fit by Using R ..................................................................337
Appendix: Tables for Your Reference . . . . . . . . . . . . . . . . . . . . . . . . . .339
t-Table............................................................................................................339
Binomial Table..............................................................................................341
Chi-Square Table ..........................................................................................346
Rank Sum Table ............................................................................................348
F-Table ...........................................................................................................349
Index........................................................................351