Statistics for Social Workers

by Weinbach, Robert W.; Grinnell, Richard M.

• ISBN13: 9780205484225
• ISBN10: 0205484220
• Edition: 7th
• Format: Paperback
• Copyright: 2007-01-01
• Publisher: Allyn & Bacon

Summary

This widely acclaimed statistics text, emphasizing a conceptual understanding of the topic and its contribution to evidence-based practice, requires no prior knowledge of statistics. It helps students by discussing the types of statistical analyses that are most likely to be encountered by social work practitioners and researchers. Book jacket.

Table of Contents

Preface	xiii
Introduction	1	(21)
Uses of Statistics	2	(1)
Methodological Terms	3	(7)
Data	3	(1)
Information	3	(1)
Variables and Constants	4	(1)
Conceptualization	5	(1)
Operationalization	6	(1)
Reliability	7	(1)
Validity	7	(1)
Research Hypotheses	8	(2)
Measurement Levels	10	(4)
Nominal	11	(1)
Ordinal	12	(1)
Interval	13	(1)
Ratio	14	(1)
Measurement Levels and Data Analysis	14	(2)
Additional Measurement Classifications	16	(1)
Discrete and Continuous Variables	16	(1)
Dichotomous, Binary, and Dummy Variables	16	(1)
Categories of Statistical Analyses	17	(1)
Number of Variables in an Analysis	17	(1)
Primary Purpose of the Analysis	17	(1)
Analysis of Qualitative Data	18	(1)
Concluding Thoughts	19	(1)
Study Questions	20	(2)
Frequency Distributions and Graphs	22	(18)
Frequency Distributions	23	(4)
Absolute Frequency Distributions	24	(1)
Cumulative Frequency Distributions	25	(1)
Percentage Frequency Distributions	25	(1)
Cumulative Percentage Frequency Distributions	26	(1)
Grouped Frequency Distributions	27	(1)
Using Frequency Distributions to Analyze Data	28	(2)
Misrepresentation of Data	30	(1)
Graphs	31	(6)
Bar Graphs and Line Diagrams	32	(1)
Pie Charts	32	(2)
Histograms	34	(1)
Frequency Polygons	35	(1)
Stem-and-Leaf Plots	36	(1)
A Common Mistake in Displaying Data	37	(1)
Concluding Thoughts	38	(1)
Study Questions	38	(2)
Measures of Central Tendency and Variability	40	(20)
Measures of Central Tendency	40	(8)
The Mode	41	(1)
The Median	41	(2)
The Mean	43	(3)
Which Measure of Central Tendency to Use?	46	(2)
Measures of Variability	48	(9)
The Range	49	(1)
The Interquartile Range	50	(1)
The Mean Deviation	51	(1)
Variance	52	(1)
Standard Deviation	52	(4)
Reporting Measures of Variability	56	(52)
Other Uses for Central Tendency and Variability	57	(1)
Concluding Thoughts	58	(1)
Study Questions	58	(2)
The Normal Distribution	60	(19)
Skewness	60	(2)
Kurtosis	62	(1)
Normal Distributions	63	(5)
Converting Raw Scores to Z Scores and Percentiles	68	(7)
Practical Uses of z Scores	72	(3)
Deriving Raw Scores from Percentiles	75	(2)
Concluding Thoughts	77	(1)
Study Questions	77	(2)
The Basics of Hypothesis Testing	79	(23)
Alternative Explanations	80	(4)
Rival Hypotheses	80	(1)
Research Design Flaws	81	(2)
Sampling Error	83	(1)
Probability and Inference	84	(1)
Refuting Sampling Error	85	(2)
Replication	85	(1)
Statistical Analyses	86	(1)
More About Research Hypotheses	87	(2)
The One-Tailed Research Hypothesis	88	(1)
The Two-Tailed Research Hypothesis	88	(1)
The ``No Relationship'' Research Hypothesis	88	(1)
Testing the Null Hypothesis	89	(2)
Statistical Significance	91	(3)
p Values	92	(1)
Rejection Levels (``Alpha'')	93	(1)
Errors in Drawing Conclusions About Relationships	94	(2)
Avoiding Type I Errors	95	(1)
Statistically Significant Relationships and Meaningful Findings	96	(3)
Assessing Strength of Relationships (Effect Size)	97	(1)
Is the Relationship Surprising?	98	(1)
Complex Interpretations of Statistically Significant Relationships	99	(1)
Concluding Thoughts	99	(1)
Study Questions	100	(2)
Sampling Distributions and the Null Hypothesis Testing	102	(17)
Sample Size and Sampling Error	103	(1)
Sampling Distributions and Inference	104	(3)
Comparing an Experimental Sample with Its Population	105	(1)
Comparing a Non-Experimental Sample with Its Population	106	(1)
Sampling Distribution of Means	107	(8)
Samples Drawn from Normal Distributions	109	(5)
Samples Drawn from Skewed Distributions	114	(1)
Estimating Parameters	115	(3)
Constructing a 95 Percent Confidence Interval	116	(1)
Constructing a 99 Percent Confidence Interval	116	(2)
Concluding Thoughts	118	(1)
Study Questions	118	(1)
Selecting a Statistical Test	119	(18)
The Importance of Selecting the Correct Test	119	(2)
Where Can We Go Wrong?	120	(1)
Factors to Consider	121	(7)
Sampling Method(s) Used	122	(1)
Distribution of the Variables within the Population	123	(1)
Level of Measurement of the Variables	123	(1)
Desirable Amount of Statistical Power	124	(4)
Robustness of Tests Being Considered	128	(1)
Parametric and Nonparametric Tests	128	(2)
Multivariate Tests	130	(1)
Deciding Which Test to Use	131	(1)
More About Getting Help	132	(1)
The Process of Hypothesis Testing	133	(2)
Concluding Thoughts	135	(1)
Study Questions	135	(2)
Correlation	137	(28)
Uses of Correlation	137	(1)
Scattergrams	138	(3)
Perfect Correlations	141	(2)
Nonperfect Correlations	143	(1)
Interpreting Linear Correlations	143	(7)
Understanding Correlation Coefficients	144	(1)
Very Strong Correlations	145	(2)
Correlation is Not Causation	147	(1)
Using Correlation for Inference	148	(2)
Pearson's r	150	(5)
Computation and Presentation	150	(5)
Nonparametric Alternatives	155	(2)
Spearman's Rho and Kendall's Tau	155	(2)
Correlation with Three or More Variables	157	(3)
Partial r	157	(1)
Multiple R	158	(1)
Variations of Multiple R	159	(1)
Other Multivariate Tests That Use Correlation	160	(3)
Factor Analysis	161	(1)
Cluster Analysis	162	(1)
Concluding Thoughts	163	(1)
Study Questions	164	(1)
Regression Analyses	165	(25)
What is Prediction?	165	(3)
What is Simple Linear Regression?	168	(2)
Formulating a Research Question	169	(1)
Limitations of Simple Linear Regression	170	(1)
Computation of the Regression Equation	170	(2)
More About the Regression Line	172	(6)
The Least-squares Criterion	174	(3)
Interchanging X and Y Variables	177	(1)
Interpreting Results	178	(3)
Presentation of Y'	178	(1)
The Standard Error	178	(1)
Using Regression in Social Work Practice	179	(2)
Regression with Three or More Variables	181	(4)
Other Types of Regression Analyses	185	(3)
Discriminant Analysis	185	(1)
Logistic Regression	186	(2)
Concluding Thoughts	188	(1)
Study Questions	189	(1)
Cross Tabulation	190	(27)
The Chi-Square Test of Association	190	(18)
Observed Frequencies	192	(2)
Expected Frequencies	194	(2)
Degrees of Freedom	196	(1)
Using Chi-Square	196	(3)
Presentation of Findings	199	(1)
Interpreting the Results of a Chi-Square Analysis	200	(1)
Meaningfulness and Sample Size	201	(3)
Restrictions on the Use of Chi-Square	204	(1)
An Alternative: Fisher's Exact Test	204	(1)
Using Chi-Square in Social Work Practice	205	(3)
Cross Tabulation with Three or More Variables	208	(3)
Problems with Sizes of Expected Frequencies	210	(1)
Effects of Introducing Additional Variables	210	(1)
Special Applications of the Chi-Square Formula	211	(4)
McNemar's Test	211	(2)
The Median Test	213	(2)
Concluding Thoughts	215	(1)
Study Questions	216	(1)
t Tests and Analysis of Variance	217	(32)
The Use of tTests	218	(1)
Misuse of t	218	(1)
The One-Sample tTest	219	(7)
Determining If a Sample is Representative	221	(1)
Hypothesis Testing	222	(1)
Presentation of Findings	223	(1)
A Nonparametric Alternative: Chi-Square Goodness of Fit	223	(3)
The Dependent tTest	226	(4)
Use with Two Connected (or Matched) Samples Measured Once	226	(1)
Use with One Sample Measured Twice	227	(1)
A Nonparametric Alternative: Wilcoxon Sign	228	(2)
The Independent tTest	230	(13)
Nonparametric Alternatives: U and K-s	239	(3)
A Multivariate Alternative: T2	242	(1)
Simple Analysis of Variance (Simple Anova)	243	(3)
Additional Data Analyses	245	(1)
A Nonparametric Alternative: Kruskal-Wallis	246	(1)
Multivariate Analysis of Variance	246	(1)
Concluding Thoughts	247	(1)
Study Questions	247	(2)
Other Contributions of Statistics to Evidence-Based Practice	249	(19)
Meta-Analysis	250	(3)
Answers Sought in Program Evaluations	253	(1)
Needs Assessments and Formative Evaluations	253	(1)
Outcome Evaluations	254	(5)
Hypothesis Testing in Outcome Evaluations	254	(3)
Statistical Analyses of Outcome Evaluation Data	257	(2)
Answers Sought in Single-System Research	259	(7)
Hypothesis Testing in Single-System Research	259	(1)
Statistical Analyses of Single-System Data	260	(1)
Using Familiar Statistical Tests	261	(1)
Two Other Popular Tests	262	(4)
Concluding Thoughts	266	(1)
Study Questions	267	(1)
Appendix A Beginning to Select a Statistical Test	268	(2)
Glossary	270	(19)
Index	289