Applied Statistics in Occupational Safety and Health / Edition 3

by Christopher A. Janicak CSP, CEA, ARM

Overview

Created for those who have little experience with statistics, or for those who need to keep a concise reference book on hand, this newly updated handbook provides an introductory guide to basic statistics and data analysis.

Using step-by-step methods and both examples and applications common to safety professionals, including loss control consultants and occupational health nurses, this new edition makes understanding the "math" side of the job easier. Readers will learn how to apply appropriate statistical procedures to commonly encountered situations, how to perform each statistical test, how to executive inferential statistics for parametric and non-parametric procedures, and how to use descriptive statistical concepts to summarize data.

The author ends each chapter with a chapter summary and review exercises. He also includes extensive illustrations, easy-to-read charts and tables, a glossary of statistical terms, a comprehensive index, solutions to sample problems, and five appendices containing statistical tables with their appropriate uses. This third edition provides new examples and numerous updates.

Product Details

ISBN-13:	9781598888881
Publisher:	Bernan Press
Publication date:	01/09/2017
Edition description:	Third Edition
Pages:	188
Sales rank:	1,116,914
Product dimensions:	6.90(w) x 9.90(h) x 0.60(d)
Age Range:	18 Years

About the Author

Christopher A. Janicak, Ph.D., CSP, ARM, is a Professor of Safety and Graduate Program Coordinator at Indiana University of Pennsylvania, Department of Safety Sciences. Dr. Janicak has over 20 years of professional experience in safety as a loss control consultant, safety manager, and university professor. He has presented at many national and international conferences, and has published books, book chapters, and journal articles in the field of occupational safety.

Table of Contents

List of Figures and Tables xiii

1 Fundamentals of Statistics 1

Statistics and Their Use in Safety 1

Statistics Defined 2

Common Terms and Notations 2

Quantitative Data and Qualitative Data 2

Statistical Notations 3

Research Questions and Hypotheses 3

Types of Studies 4

Retrospective Studies 4

Prospective Studies 4

Experiments 4

Statistical Samples versus Statistical Populations 5

Bias 5

Probability Sample Selection Procedures 6

Sampling Techniques 6

Random Samples 6

Simple Random Samples 6

Using a Random Numbers Table 7

Random Numbers Table Example 7

Cluster Samples 8

Stratified Random Samples 8

Nonprobabihty Sample Selection Procedures 8

Chunk Sampling 9

Volunteer Samples 9

Variables 9

Dependent and Independent Variables 9

Summary 9

Review Exercises 10

2 Probability and Chance 13

Probability 13

Marginal Probabilities 13

Joint Probabilities 14

Union Probabilities 14

Conditional Probabilities 16

Factorials, Permutations, Ordered Combinations, and Combinations 17

Factorials 17

Permutations 17

Combinations 18

Binomial Probabilities 19

Poisson Probability 20

Summary 21

Review Exercises 22

3 Distributions 23

Statistical Distributions and Populations 23

Frequencies 23

Histograms 24

Frequency Polygons 25

Percentages, Cumulative Percentages, and Percentiles 26

Normal Distribution 26

Binomial Distribution 27

T Distribution 29

Chi-Square Distribution 30

F Distribution 31

Summary 31

Review Exercises 32

4 Descriptive Statistics 33

Data Formats 33

Categorical Data 33

Ordinal Data 33

Interval Data 34

Ratio Data 34

Strength of the Data Formats 34

Measures of Central Tendency 34

Mean 35

Median 35

Mode 35

Measures of Variability 36

Range 36

Variance 36

Variance Calculation 37

Standard Deviation 37

Interquartile Range 38

z-Scores 38

z-Scores and Percentages of the Population 39

Confidence Intervals for Means 41

95% Confidence Intervals 42

99% Confidence Intervals 42

Interpreting Confidence Intervals 43

Summary 43

Review Exercises 43

5 Statistical Tests 45

Statistical Hypotheses 45

Inferential Statistical Testing 46

Type I and Type II Errors 46

Alpha Levels 47

Statistical Power of a Test 47

Inferential Statistics Test Procedure 48

Developing a Statistical Hypothesis 48

Choosing the Appropriate Statistical Test or Procedure 48

Determining the Statistical Distribution 48

Determining Significance Levels 48

Formulating a Decision Rule 49

Running the Test 49

Formulating a Conclusion and Making a Decision 49

Summary 49

Review Exercises 50

6 Inferential Statistics for Means 51

Z-Test Comparing a Sample Mean to a Known Population Mean 51

Test Assumptions 51

Hypothesis Construction 51

Determine Significance Levels 52

Using a z-Table 52

Formulate a Decision Rule 53

Z-Test Formula 53

Conclusions 53

Example z-Test Problem 53

Independent Samples z-Test 54

Test Assumptions 54

Independent Samples z-Test Formula 55

Example Independent Samples c-Test Problem 55

Hypothesis Construction 56

Conclusions 56

T-Test for a Single Mean 56

Test Assumptions 56

Hypothesis Construction 57

Determine Significance Levels 57

Formulate a Decision Rule 57

T-Test Formula for a Single Mean 58

Conclusions 58

Example f-Test Problem 58

T-Test for Independent Samples 59

Paired Samples f-Tests 60

Test Assumptions 60

Hypothesis Construction 60

Determine Significance Levels 60

Formulate a Decision Rule 60

Test Formula 61

Conclusions 61

Example Paired Sample t-Test Problem 61

Calculate t 62

One-Way Analysis of Variance 62

Procedure Assumptions 63

Hypothesis Construction 63

Procedure Formulas 63

Hypothesis Construction 66

Formulate a Decision Rule 67

Calculate F Ratio 67

Conclusions 67

Post Hoc Procedures 67

Tukey's HSD 67

Calculate Tukey's HSD 68

Formulate a Decision Rule 68

Example ANOVA Problem 69

Formulate a Decision Rule 71

Calculate F Ratio 71

Conclusions 71

Run Post Hoc Tests 71

Summary 72

Review Exercises 72

7 Correlation and Regression 75

Correlation 75

Pearson Correlation Coefficient 77

Assumptions 77

Pearson Correlation Coefficient Formula 77

Sample Problem 77

Significance Testing for Correlation Coefficients 78

Test Hypotheses 78

Test Formula 78

Sample Problem 79

Spearman Rank-Order Correlation Coefficient 79

Assumptions 79

Spearman Rank-Order Correlation Coefficient Formula 80

Sample Problem 80

Phi Coefficient 81

Assumptions 81

Phi Coefficient Formula 81

Sample Problem 81

Point Biserial Correlation 82

Assumptions 82

Point Biserial Correlation Formula 82

Sample Problem 82

Linear Regression 83

Procedure Assumptions 84

Linear Regression Formulas 84

Sample Problem 84

Summary 86

Review Exercises 86

8 Nonparametric Statistics 89

Underlying Assumptions Concerning Nonparametric Statistics 89

Chi-Square Test for Goodness of Fit 89

Degrees of Freedom 89

Test Assumptions 90

Hypothesis Construction 90

Test Formula 90

Determining the Critical Value 90

Sample Problem 90

X² Test of independence 92

Degrees of Freedom 92

Expected Number of Cases 92

Test Assumptions 92

Hypothesis Construction 92

Test Formula 92

Sample Problem 93

Cochran's Q Test 94

Test Assumptions 94

Hypothesis Construction 94

Cochran's Q Test Formula 94

Sample Problem 95

Summary 96

Review Exercises 97

9 Survey Research 99

Types of Survey Studies 99

Collecting and Maintaining Survey Data 99

Outline for Planning a Survey 100

Constructing the Instrument 101

Types of Survey Items 102

Forms of Questions 102

Unstructured Questions 102

Structured Questions 103

Rating Scales 104

Likert Scales 104

Semantic Differential Scales 104

Formatting Questionnaires for the Mail 105

Sound Survey Research Procedures 105

Measurable Objective 105

Representative Population 106

Match the Hypothesis to the Statistical Tests 106

Conduct Background Research 106

Instrument Validity and Reliability 106

Cover Letters and Instructions 107

Sampling for Surveys 107

Calculating Sample Sizes 107

Survey Research Limitations 108

Pilot Testing 108

Permission to Use Human Subjects 108

Summary 109

Review Exercises 109

10 Experimental Design 111

Experimental Design Uses 111

Research Hypotheses and Experimental Design 111

Dependent and Independent Variables 112

Types of Experimental Designs 112

One-Way ANOVA 112

Completely Randomized Design 113

Randomized Block Design 113

Latin Square Design 113

Completely Randomized Factorial Design 113

Summary 114

Review Exercises 114

11 Presenting Research 117

Data Presentation for Safety Professionals 117

Displaying Descriptive Statistics 117

Displaying Tables 117

Example Table 118

Column Charts 118

Pie Charts 118

Presenting Inferential Statistics 119

Z-Tests and t-Tests 119

Example Results from a Paired t-Test Procedure 119

One-Way Analysis of Variance 120

Correlation Procedures 120

Regression Procedures 120

Nonparametric Procedures 120

Using Computer Software to Develop Presentations 121

Sample Data Analysis Using Microsoft Excel 121

Developing Presentations Using Microsoft Office 123

Summary 123

Review Exercises 123

Appendix 125

Statistical Tables 125

Cumulative Distribution Function for the Standard Normal Random Variable 125

Critical Values for the t Distribution 127

Critical Values for the Chi-Square Distribution 128

Critical Values for the F Distribution 129

Table of Random Units 130

Critical Values of the Studentized Range 132

Glossary of Terms 137

References 145

Solutions to Selected Sample Problems 149

Index 169

About the Author 173

Editorial Reviews

Provides occupational safety and health professionals with an introductory guide to basic statistic and data analysis. Uses step-by- step methods and examples and applications common to safety professionals to explain how to apply appropriate statistical procedures to commonly encountered situations. Gives methods for applying statistics properly, describes detailed procedures for each statistical test and methods for using them, presents descriptive statistical concepts and explains how they can be used to summarize data, and examines inferential statistics for parametric and non- parametric procedures. Includes summaries, exercises, and solutions, plus five appendices of statistical tables. The author is assistant professor of safety and director of the Safety Program at Illinois State University. Annotation c. Book News, Inc., Portland, OR (booknews.com)

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