Preface 

ix  



An Overview of Educational Research 


3  (18) 

Basic (Pure), Applied, and Action Research 


3  (1) 

Quantitative vs. Qualitative Research 


4  (1) 

Experimental vs. Nonexperimental Research 


5  (12) 


5  (2) 

Threats to Internal Validity 


7  (1) 

Threats to External Validity 


8  (1) 


8  (4) 


12  (3) 


15  (1) 

CasualComparative (ex post facto) Reasearch 


15  (1) 


15  (2) 


17  (4) 

Basic Concepts in Statistics 


21  (22) 

Variables and Measurement Scales 


21  (2) 


22  (1) 


22  (1) 


22  (1) 


22  (1) 


23  (1) 

Parameters and Statistics 


23  (1) 


24  (1) 


24  (1) 


24  (1) 


25  (1) 


25  (1) 


25  (1) 


26  (1) 

Parametric and Nonparametric Statistics 


26  (1) 

Descriptive and Inferential Statistics 


27  (1) 

Using Hypotheses in Research 


27  (2) 

Alternative and Null Hypotheses 


28  (1) 

Directional and Nondirectional Hypotheses 


28  (1) 

Probability and Level of Significance 


29  (1) 

Errors in Decision Making 


30  (1) 


30  (1) 


30  (3) 

Using Samples to Estimate Population Values 


33  (2) 

Standard Error of the Mean 


34  (1) 


34  (1) 

Steps in the Process of Hypothesis Testing 


35  (1) 


36  (1) 


36  (7) 

Part Two: Descriptive Statistics 



Organizing and Graphing Data 


43  (18) 


43  (4) 


43  (1) 


44  (1) 

Cumulative Frequency Distributions 


45  (2) 


47  (11) 

Histogram and Frequency Polygon 


47  (3) 

Comparing Histograms and Frequency Polygons 


50  (1) 

Graphing Cumulative Frequency Distributions 


50  (1) 


51  (1) 


52  (3) 


55  (1) 


56  (2) 


58  (1) 


59  (2) 

Measures of Central Tendency 


61  (6) 


61  (1) 


62  (1) 


63  (1) 

Comparing the Mode, Median, and Mean 


64  (1) 


65  (2) 


67  (12) 


68  (1) 


68  (1) 

Standard Deviation and Variance 


69  (5) 

Computing the Variance and SD for Populations and Samples 


71  (1) 

Using the Variance and SD 


72  (1) 

Variance and SD in Distributions with Extreme Scores 


73  (1) 

Factors Affecting the Variance and SD 


73  (1) 


74  (5) 

Part Three: The Normal Curve and Standard Scores 



The Normal Curve and Standard Scores 


79  (10) 


79  (2) 


81  (5) 


82  (1) 


83  (1) 


84  (1) 

The Normal Curve and Percentile Ranks 


84  (2) 


86  (3) 


89  (8) 


89  (3) 


90  (1) 


91  (1) 


91  (1) 

CriterionReferenced Tests 


92  (1) 


93  (4) 

Part Four: Measuring Relationships 




97  (14) 


97  (4) 


101  (3) 

Interpreting the Correlation Coefficient 


101  (1) 

Hypotheses for Correlation 


102  (1) 

Computing Pearson Correlation 


103  (1) 

Factors Affecting the Correlation 


104  (2) 

The Coefficient of Determination 


106  (1) 


107  (1) 


108  (1) 


109  (2) 

Prediction and Regression 


111  (12) 


112  (6) 

The Standard Error of Estimate (SE) 


114  (1) 

An Example of Simple Regression 


114  (2) 

Computing the Standard Error of Estimate 


116  (1) 

Graphing the Regression Equation 


117  (1) 

The Coefficient of Determination (r2) 


117  (1) 


118  (1) 


119  (4) 

Part Five: Inferential Statistics 




123  (12) 


123  (2) 


125  (1) 

t Test for Independent Samples 


125  (4) 

An Example of a t Test for Independent Samples 


126  (3) 

t Test for Paired Samples 


129  (2) 

An Example of a t Test for Paired Samples 


130  (1) 

t Test for a Single Sample 


131  (2) 

An Example of a Single Sample t Test 


132  (1) 


133  (2) 


135  (18) 


137  (8) 

Conceptualizing the OneWay ANOVA 


137  (3) 

Hypotheses for a OneWay ANOVA 


140  (1) 


140  (1) 

Further Interpretation of the F Ratio 


140  (1) 

An Example of a OneWay ANOVA 


141  (2) 


143  (2) 


145  (6) 

Conceptualizing the TwoWay ANOVA 


145  (1) 

Hypotheses for the TwoWay ANOVA 


145  (1) 


146  (2) 

The TwoWay ANOVA Summary Table 


148  (1) 

An Example of a TwoWay ANOVA 


148  (3) 


151  (2) 


153  (10) 

Assumptions for the Chi Square Test 


154  (1) 

The Goodness of Fit Chi Square Test 


154  (2) 

Equal Expected Frequencies 


155  (1) 

Unequal Expected Frequencies 


155  (1) 

The Chi Square Test of Independence 


156  (3) 

Computation of Expected Frequencies for Chi Square Test of Independence 


159  (1) 


160  (3) 

Part Six: Reliability and Validity 




163  (8) 

Understanding the Theory of Reliability 


163  (1) 

Methods of Assessing Reliability 


164  (3) 


164  (1) 

Alternate Forms Reliability 


165  (1) 

Measures of Internal Consistency 


165  (1) 


166  (1) 

The Standard Error of Measurement 


167  (1) 

Factors Affecting Reliability 


168  (1) 

Heterogeneity of the Group 


168  (1) 


168  (1) 


168  (1) 


168  (1) 

How High Should the Reliability Be? 


168  (1) 


169  (2) 


171  (6) 


171  (1) 

CriterionRelated Validity 


172  (1) 


172  (1) 


172  (1) 


173  (1) 


173  (1) 


173  (1) 


174  (1) 


174  (3) 

Part Seven: Conducting Your Own Research 



Planning and Conducting Research Studies 


177  (10) 


178  (1) 


178  (4) 


179  (1) 


180  (1) 


180  (2) 


182  (1) 


182  (2) 


183  (1) 


184  (1) 


184  (3) 

Choosing the Right Statistical Tests 


187  (8) 

Choosing a Statistical Test: A Decision Flowchart 


187  (2) 


189  (1) 


189  (1) 


189  (1) 


190  (2) 


192  (3) 


195  (14) 

Appendix A: Z Scores and Percentage of Area Under the Normal Curve Between any Given ZScore and the Mean 


197  (3) 

Appendix B: Values of the Correlation Coefficient (Pearson's r) for Different Levels of Significance 


200  (1) 

Appendix C: Distribution of t 


201  (1) 

Appendix D: The 5 Percent and 1 Percent Points for the Distribution of F 


202  (4) 

Appendix E: Distribution of Studentized Range Statistic 


206  (2) 

Appendix F: Distribution of Chi Square (Χ2) 


208  (1) 
List of Statistical Symbols 

209  (2) 
Glossary 

211  (10) 
Index 

221  