Statistics

Drawing upon over 40 years of experience, the authors of Statistics, 10th Edition provide business professionals with a clear and methodical approach to essential statistical procedures. The text clearly explains the basic concepts and procedures of descriptive and inferential statistical analysis. It features an emphasis on expressions involving sums of squares and degrees of freedom as well as a strong stress on the importance of variability. This accessible approach will help business professionals tackle such perennially mystifying topics as the standard deviation, variance interpretation of the correlation coefficient, hypothesis tests, degrees of freedom, p–values, and estimates of effect size.

Table of Contents:
Preface V Acknowledgments VII 1 Introduction 3 1.1 Why Study Statistics? 4 1.2 What Is Statistics? 4 1.3 More About Inferential Statistics 6 1.4 Three Types Of Data 9 1.5 Levels Of Measurement 10 1.6 Types Of Variables 14 1.7 How To Use This Book 19 Summary20 Important Terms 21 Review Questions 21 Part 1 Descriptive Statistics: Organizing And Summarizing Data 25 2 Describing Data With Tables And Graphs 27 Tables (Frequency Distributions) 28 2.1 Frequency Distributions For Quantitative Data 28 2.2 Guidelines 29 2.3 Outliers 34 2.4 Relative Frequency Distributions 35 2.5 Cumulative Frequency Distributions 36 2.6 Frequency Distributions For Qualitative (Nominal) Data 38 2.7 Interpreting Distributions Constructed By Others 39 Graphs 40 2.8 Graphs For Quantitative Data 40 2.9 Typical Shapes 45 2.10 A Graph For Qualitative (Nominal) Data 47 2.11 Misleading Graphs 48 2.12 Doing It Yourself 50 Summary 50 Important Terms 52 Review Questions 53 3 Describing Data With Averages 57 3.1 Mode 58 3.2 Median 59 3.3 Mean 61 3.4 Which Average? 63 3.5 Averages For Qualitative And Ranked Data 66 Summary 68 Important Terms 68 Key Equation 69 Review Questions 69 4 Describing Variability 73 4.1 Intuitive Approach 74 4.2 Range 76 4.3 Variance 76 4.4 Standard Deviation 77 4.5 Details: Standard Deviation 82 4.6 Degrees Of Freedom(Df) 90 4.7 Interquartile Range (Iqr) 92 4.8 Measures Of Variability For Qualitative And Ranked Data 93 Summary 93 Important Terms 94 Key Equations 95 Review Questions 95 5 Normal Distributions And Standard (Z) Scores 99 5.1 The Normal Curve 101 5.2 Z Scores 103 5.3 Standard Normal Curve 104 5.4 Solving Normal Curve Problems 107 5.5 Finding Proportions 108 5.6 Finding Scores 114 5.7 More About Z Scores 119 Summary 122 Important Terms 123 Key Equations 123 Review Questions 123 6 Describing Relationships: Correlation 127 6.1 An Intuitive Approach 128 6.2 Scatterplots 130 6.3 A Correlation Coefficient For Quantitative Data: R 133 6.4 Details: Computation Formula For R 141 6.5 Outliers Again 143 6.6 Other Types Of Correlation Coefficients 144 6.7 Computer Output 144 Summary 148 Important Terms 149 Key Equations 149 Review Questions 149 7 Regression 153 7.1 Two Rough Predictions 154 7.2 A Regression Line 155 7.3 Least Squares Regression Line 157 7.4 Standard Error Of Estimate, Sy|X 161 7.5 Assumptions 164 7.6 Interpretation Of 7.7 Multiple Regression Equations 164 7.8 Regression Toward The Mean 165 Summary 167 Important Terms 168 Key Equations 168 Review Questions 168 Part 2 Inferential Statistics: Generalizing Beyond Data 171 8 Populations, Samples, And Probability 173 Populations And Samples 174 8.1 Populations 174 8.2 Samples 175 8.3 Random Sampling 176 8.4 Tables Of Random Numbers 177 8.5 Random Assignment Of Subjects 179 8.6 Surveys Or Experiments? 180 Probability 181 8.7 Definition 181 8.8 Addition Rule 182 8.9 Multiplication Rule 183 8.10 Probability And Statistics 186 Summary 188 Important Terms 188 Key Equations 189 Review Questions 189 9 Sampling Distribution Of The Mean 193 9.1 What Is A Sampling Distribution? 194 9.2 Creating A Sampling Distribution From Scratch 195 9.3 Some Important Symbols 197 9.4 Mean Of All Sample Means () 199 9.5 Standard Error Of The Mean () 200 9.6 Shape Of The Sampling Distribution 202 9.7 Other Sampling Distributions 204 Summary 205 Important Terms 205 Key Equations 205 Review Questions 206 10 Introduction To Hypothesis Testing: The Z Test 209 10.1 Testing A Hypothesis About Sat Scores 210 10.2 Z Test For A Population Mean 212 10.3 Step–By–Step Procedure 214 10.4 Statement Of The Research Problem 214 10.5 Null Hypothesis (H0) 215 10.6 Alternative Hypothesis (H1) 216 10.7 Decision Rule 217 10.8 Calculations 218 10.9 Decision 218 10.10 Interpretation 219 Summary 220 Important Terms 221 Key Equations 221 Review Questions 221 11 More About Hypothesis Testing 225 11.1 Why Hypothesis Tests? 226 11.2 Strong Or Weak Decisions 228 11.3 One–Tailed And Two–Tailed Tests 229 11.4 Choosing A Level Of Significance (a) 233 11.5 Testing A Hypothesis About Vitamin C 235 11.6 Four Possible Outcomes 235 11.7 If H0 Really Is True 238 11.8 If H0 Really Is False Because Of A Large Effect 239 11.9 If H0 Really Is False Because Of A Small Effect 242 11.10 Influence Of Sample Size 243 11.11 Power And Sample Size 246 Summary 249 Important Terms 251 Review Questions 251 12 Estimation (Confidence Intervals) 255 12.1 Point Estimate For m 256 12.2 Confidence Interval (Ci) For m 256 12.3 Interpretation Of A Confidence Interval 260 12.4 Level Of Confidence 261 12.5 Effect Of Sample Size 262 12.6 Hypothesis Tests Or Confidence Intervals? 263 12.7 Confidence Interval For Population Percent 263 Summary 265 Important Terms 266 Key Equation 266 Review Questions 266 13 T Test For One Sample 269 13.1 Gas Mileage Investigation 270 13.2 Sampling Distribution Of T 270 13.3 T Test 274 13.4 Common Theme Of Hypothesis Tests 275 13.5 Reminder About Degrees Of Freedom 275 13.6 Details: Estimating The Standard Error 275 13.7 Details: Calculations For The T Test 276 13.8 Confidence Intervals For M Based On T 278 13.9 Assumptions 279 Summary 280 Important Terms 280 Key Equations 280 Review Questions 280 14 T Test For Two Independent Samples 285 14.1 Epo Experiment 286 14.2 Statistical Hypotheses 287 14.3 Sampling Distribution Of 289 14.4 T Test 91 14.5 Details: Calculations For The T Test 292 14.6 P–Values 296 14.7 Statistically Significant Results 299 14.8 Estimating Effect Size: Point Estimates And Confidence Intervals 300 14.9 Estimating Effect Size: Cohen s D 303 14.10 Meta–Analysis 14.11 Reports In The Literature 306 14.12 Assumptions 308 14.13 Computer Output 308 Summary 309 Important Terms 310 Key Equations 310 Review Questions 311 15 T Test For Two Related Samples (Repeated Measures) 315 15.1 Epo Experiment With Repeated Measures 316 15.2 Statistical Hypotheses 319 15.3 Sampling Distribution Of 320 15.4 T Test 320 15.5 Details: Calculations For The T Test 321 15.6 Estimating Effect Size 324 15.7 Assumptions 326 15.8 Overview: Three T Tests For Population Means 326 15.9 T Test For The Population Correlation Coefficient, r 329 Summary 331 Important Terms 332 Key Equations 332 Review Questions 333 16 Analysis Of Variance (One Factor) 337 16.1 Testing A Hypothesis About Sleep Deprivation And Aggression 338 16.2 Two Sources Of Variability 340 16.3 F Test 342 16.4 Details: Variance Estimates 344 16.5 Details: Mean Squares (Ms) And The F Ratio 350 16.6 Table For The F Distribution 352 16.7 Anova Summary Tables 353 16.8 F Test Is Nondirectional 355 16.9 Estimating Effect Size 355 16.10 Multiple Comparisons 358 16.11 Overview: Flow Chart For Anova 362 16.12 Reports In The Literature 362 16.13 Assumptions 364 16.14 Computer Output 364 Summary 364 Important Terms 366 Key Equations 366 Review Questions 366 17 Analysis Of Variance (Repeated Measures) 371 17.1 Sleep Deprivation Experiment With Repeated Measures 372 17.2 F Test 373 17.3 Two Complications 375 17.4 Details: Variance Estimates 375 17.5 Details: Mean Square (Ms) And The F Ratio 379 17.6 Table For The F Distribution 381 17.7 Anova Summary Tables 381 17.8 Estimating Effect Size 383 17.9 Multiple Comparisons 384 17.10 Reports In The Literature 386 17.11 Assumptions 387 Summary 387 Important Terms 388 Key Equations 388 Review Questions 388 18 Analysis Of Variance (Two Factors) 393 18.1 A Two–Factor Experiment: Responsibility In Crowds 394 18.2 Three F Tests 397 18.3 Interaction 398 18.4 Details: Variance Estimates 402 18.5 Details: Mean Squares (Ms) And F Ratios 406 18.6 Table For The F Distribution 408 18.7 Estimating Effect Size 408 18.8 Multiple Comparisons 409 18.9 Simple Effects 410 18.10 Overview: Flow Chart For Two–Factor Anova 414 18.11 Reports In The Literature 415 18.12 Assumptions 416 18.13 Other Types Of Anova 416 Summary 417 Important Terms 417 Key Equations 417 Review Questions 418 19 Chi–Square (c2) Test For Qualitative (Nominal) Data 423 One–Variable c2 Test 424 19.1 Survey Of Blood Types 424 19.2 Statistical Hypotheses 424 19.3 Details: Calculating c2 425 19.4 Table For The c 2 Distribution 428 19.5 c2 Test 428 Two–Variable c2 Test 431 19.6 Lost Letter Study 431 19.7 Statistical Hypotheses 432 19.8 Details: Calculating c2 433 19.9 Table For The c2 Distribution 434 19.10 c2 Test 436 19.11 Estimating Effect Size 437 19.12 Odds Ratios 438 19.13 Reports In The Literature 440 19.14 Some Precautions 441 19.15 Computer Output 442 Summary 443 Important Terms 443 Key Equations 443 Review Questions 444 20 Tests For Ranked (Ordinal) Data 449 20.1 Use Only When Appropriate 450 20.2 A Note On Terminology 450 20.3 Mann–Whitney U Test (Two Independent Samples) 451 20.4 Wilcoxon T Test (Two Related Samples) 456 20.5 Kruskal–Wallis H Test (Three Or More Independent Samples) 460 20.6 General Comment: Ties 464 Summary 464 Important Terms 465 Review Questions 465 21 Postscript: Which Test? 469 21.1 Descriptive Or Inferential Statistics? 470 21.2 Hypothesis Tests Or Confidence Intervals? 470 21.3 Quantitative Or Qualitative Data? 472 21.4 Distinguishing Between The Two Types Of Data 472 21.5 One, Two, Or More Groups? 473 21.6 Concluding Comments 474 Review Questions 474 Appendices 479 A Math Review 479 B Answers To Selected Questions 487 C Tables 529 D Glossary 543 Photo Credits 550 Index 551