AN INTRODUCTION TO STATISTICAL ANALYSIS IN RESEARCH

606 Pages·1845·40.38 MB·english

by  WILEY

AnIntroductiontoStatistical
AnalysisinResearch
An Introduction to Statistical
Analysis in Research
WithApplicationsintheBiologicalandLifeSciences
KathleenF.Weaver
VanessaC.Morales
SarahL.Dunn
KanyaGodde
PabloF.Weaver
Thiseditionfirstpublished2018
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LibraryofCongressCataloging-in-PublicationData
Names:Weaver,KathleenF.
Title:Anintroductiontostatisticalanalysisinresearch:with
applicationsinthebiologicalandlifesciences/KathleenF.Weaver[andfourothers].
Description:Hoboken,NJ:JohnWiley&Sons,Inc.,2017.|Includesindex.
Identifiers:LCCN2016042830|ISBN9781119299684(cloth)|ISBN9781119301103(epub)
Subjects:LCSH:Mathematicalstatistics–Dataprocessing.|Multivariate
analysis–Dataprocessing.|Lifesciences–Statisticalmethods.
Classification:LCCQA276.4.I652017|DDC519.5–dc23LCrecordavailable
athttps://lccn.loc.gov/2016042830
Coverimage:Courtesyoftheauthor
CoverdesignbyWiley
Setin11/14ptWarnockProbyAptaraInc.,NewDelhi,India
10 9 8 7 6 5 4 3 2 1
v
Contents
Preface ix
Acknowledgments xi
AbouttheCompanionWebsite xiii
 ExperimentalDesign 1
1.1 ExperimentalDesignBackground 1
1.2 SamplingDesign 2
1.3 SampleAnalysis 7
1.4 Hypotheses 9
1.5 Variables 10
 CentralTendencyandDistribution 13
2.1 CentralTendencyandOtherDescriptiveStatistics 13
2.2 Distribution 18
2.3 DescriptiveStatisticsinExcel 34
2.4 DescriptiveStatisticsinSPSS 48
2.5 DescriptiveStatisticsinNumbers 52
2.6 DescriptiveStatisticsinR 57
 ShowingYourData 61
3.1 BackgroundonTablesandGraphs 61
3.2 Tables 62
3.3 BarGraphs,Histograms,andBoxPlots 63
3.4 LineGraphsandScatterPlots 136
3.5 PieCharts 165
 ParametricversusNonparametricTests 191
4.1 Overview 192
4.2 Two-SampleandThree-SampleTests 194
 t-Test 195
5.1 Student’st-TestBackground 195
vi Contents
5.2 Examplest-Tests 196
5.3 CaseStudy 201
5.4 ExcelTutorial 205
5.5 Pairedt-TestSPSSTutorial 209
5.6 Independentt-TestSPSSTutorial 213
5.7 NumbersTutorial 218
5.8 RIndependent/Paired-Samplest-TestTutorial 223
 ANOVA 227
6.1 ANOVABackground 227
6.2 CaseStudy 236
6.3 One-WayANOVAExcelTutorial 241
6.4 One-WayANOVASPSSTutorial 247
6.5 One-WayRepeatedMeasuresANOVASPSSTutorial 252
6.6 Two-WayRepeatedMeasuresANOVASPSSTutorial 261
6.7 One-WayANOVANumbersTutorial 272
6.8 One-WayRTutorial 288
6.9 Two-WayANOVARTutorial 291
 Mann–WhitneyUandWilcoxonSigned-Rank 297
7.1 Mann–WhitneyUandWilcoxonSigned-RankBackground 297
7.2 Assumptions 298
7.3 CaseStudy–Mann—WhitneyUTest 299
7.4 CaseStudy–WilcoxonSigned-Rank 302
7.5 Mann–WhitneyUExcelTutorial 305
7.6 WilcoxonSigned-RankExcelTutorial 313
7.7 Mann–WhitneyUSPSSTutorial 319
7.8 WilcoxonSigned-RankSPSSTutorial 324
7.9 Mann–WhitneyUNumbersTutorial 328
7.10 WilcoxonSigned-RankNumbersTutorial 337
7.11 Mann–WhitneyU/WilcoxonSigned-RankRTutorial 350
 Kruskal–Wallis 353
8.1 Kruskal–WallisBackground 353
8.2 CaseStudy1 354
8.3 CaseStudy2 358
8.4 Kruskal–WallisExcelTutorial 362
8.5 Kruskal–WallisSPSSTutorial 368
8.6 Kruskal–WallisNumbersTutorial 375
8.7 Kruskal–WallisRTutorial 386
 Chi-SquareTest 393
9.1 Chi-SquareBackground 393
9.2 CaseStudy1 394
Contents vii
9.3 CaseStudy2 401
9.4 Chi-SquareExcelTutorial 405
9.5 Chi-SquareSPSSTutorial 418
9.6 Chi-SquareNumbersTutorial 426
9.7 Chi-SquareRTutorial 429
 Pearson’sandSpearman’sCorrelation 435
10.1 CorrelationBackground 435
10.2 Example 435
10.3 CaseStudy–Pearson’sCorrelation 442
10.4 CaseStudy–Spearman’sCorrelation 445
10.5 Pearson’sCorrelationExcelandNumbersTutorial 448
10.6 Spearman’sCorrelationExcelTutorial 455
10.7 Pearson/Spearman’sCorrelationSPSSTutorial 462
10.8 Pearson/Spearman’sCorrelationRTutorial 467
 LinearRegression 473
11.1 LinearRegressionBackground 473
11.2 CaseStudy 480
11.3 LinearRegressionExcelTutorial 484
11.4 LinearRegressionSPSSTutorial 497
11.5 LinearRegressionNumbersTutorial 508
11.6 LinearRegressionRTutorial 517
 BasicsinExcel 523
12.1 OpeningExcel 524
12.2 InstallingtheDataAnalysisToolPak 525
12.3 CellsandReferencing 529
12.4 CommonCommandsandFormulas 532
12.5 ApplyingCommandstoEntireColumns 534
12.6 InsertingaFunction 536
12.7 FormattingCells 537
 BasicsinSPSS 539
13.1 OpeningSPSS 539
13.2 LabelingVariables 541
13.3 SettingDecimalPlacement 543
13.4 DeterminingtheMeasureofaVariable 544
13.5 SavingSPSSDataFiles 545
13.6 SavingSPSSOutput 547
 BasicsinNumbers 551
14.1 OpeningNumbers 551
14.2 CommonCommands 553
viii Contents
14.3 ApplyingCommands 555
14.4 AddingFunctions 557
 BasicsinR 561
15.1 OpeningR 561
15.2 GettingAcquaintedwiththeConsole 562
15.3 LoadingData 566
15.4 InstallingandLoadingPackages 570
15.5 Troubleshooting 576
 Appendix 579
FlowChart 579
LiteratureCited 581
Glossary 585
Index 591
ix
Preface
This book is designed to be a practical guide to the basics of statis-
tical analysis. The structure of the book was born from a desire to
meet the needs of our own science students, who often felt discon-
nected from the mathematical basis of statistics and who struggled
with the practical application of statistical analysis software in their
research.Thus,thespecificemphasisofthistextisontheconceptual
framework of statistics and the practical application of statistics in
thebiologicalandlifesciences,withexamplesandcasestudiesfrom
biology,kinesiology,andphysicalanthropology.
Inthefirstfewchapters,thebookfocusesonexperimentaldesign,
showing data, and the basics of sampling and populations. Under-
standing biases and knowing how to categorize data, process data,
and show data in a systematic way are important skills for any
researcher. By solidifying the conceptual framework of hypothesis
testingandresearchmethods,aswellasthepracticalinstructionsfor
showing data through graphs and figures, the student will be better
equippedforthestatisticalteststocome.
Subsequent chapters delve into detail to describe many of the
parametric and nonparametric statistical tests commonly used in
research. Each section includes a description of the test, as well as
when and how to use the test appropriately in the context of exam-
plesfrombiologyandthelifesciences.Thechaptersincludein-depth
tutorials for statistical analyses using Microsoft Excel, SPSS, Apple
Numbers, and R, which are the programs used most often on col-
legecampuses,orinthecaseofR,isfreetoaccessontheweb.Each
tutorialincludessampledatasetsthatallowforpracticingandapply-
ingthestatisticaltests,aswellasinstructionsonhowtointerpretthe
x Preface
statistical outputs in the context of hypothesis testing. By building
confidencethroughpracticeandapplication,thestudentshouldgain
the proficiency needed to apply the concepts and statistical tests to
theirownsituations.
The material presented within is appropriate for anyone looking
toapplystatisticalteststodata,whetheritisforthenovicestudent,
forthestudentlookingtorefreshtheirknowledgeofstatistics,orfor
those looking for a practical step-by-step guide for analyzing data
acrossmultipleplatforms.Thisbookisdesignedforundergraduate-
level research methods and biostatistics courses and would also be
usefulasanaccompanyingtexttoanystatisticscourseorcoursethat
requiresstatisticaltestinginitscurriculum.
ExamplesfromtheBook
Thetutorialsinthisbookarebuilttoshowavarietyofapproachesto
using Microsoft Excel, SPSS, Apple Numbers, and R, so the student
can find their own unique style in working with statistical software,
aswellastoenrichthestudentlearningexperiencethroughexposure
tomoreandvariedexamples.Mostofthedatausedinthisbookwere
obtaineddirectlyfrompublishedarticlesorweredrawnfromunpub-
lisheddatasetswithpermissionfromthefacultyattheUniversityof
LaVerne.Insometutorials,dataweregeneratedstrictlyforteaching
purposes;however,datawerebasedonactualtrendsobservedinthe
literature.
xi
Acknowledgments
Thisbookwasmadepossiblebythehelpandsupportofmanyclose
colleagues, students, friends, and family; because of you, the ideas
forthisbookbecameareality.ThankyoutoJeromeGarciaandAnil
Kapoorforincorporatingearlydraftsofthisbookintoyourcourses
and for your constructive feedback that allowed it to grow and
develop. Thank you to Priscilla Escalante for your help in research-
ingtutorialdesign,AliciaGuadarramaandJeremyWagonerforbeing
ourtutorialtesters,andMargaretGoughandJosephCabreraforyour
helpful comments and suggestions; we greatly appreciate it. Finally,
thankyoutotheUniversityofLaVernefacultythatkindlyprovided
their original data to be used as examples and to the students who
inspiredthisworkfromthebeginning.