Testing and Measurement: A User-Friendly Guide [Mīkstie vāki]

List of Figures		xi
List of Tables		xii
A Note to Students		xiii
Acknowledgments		xv
1. What Is a Number? Is a Rose Always a Rose?		1	(18)
Numbers and Scales		1	(3)
Nominal		1	(1)
Ordinal		2	(1)
Interval		3	(1)
Ratio		4	(1)
Some Final Thoughts About Scales of Measurement		4	(2)
Let's Check Your Understanding		5	(1)
Our Model Answers		6	(1)
Numbers and Response Formats		6	(3)
Dichotomous Responses		7	(1)
Continuous Responses (Likert Scales and Their Cousins)		8	(1)
Some Final Thoughts About Response Formats		9	(2)
Let's Check Your Understanding		10	(1)
Our Model Answers		10	(1)
Numbers and Test Scores—How Do They Relate?		11	(1)
Some Final Thoughts About Measurement Scales and Response Formats		12	(1)
Key Terms		12	(1)
Models and Self-instructional Exercises		13	(5)
Our Model		13	(1)
Our Model Answers		14	(1)
Now It's Your Turn		14	(2)
Our Model Answers		16	(2)
Words of Encouragement		18	(1)
2. Frequencies: One Potato, Two Potato, Three Potato, Four		19	(16)
Ungrouped Frequency Distributions		19	(3)
Grouped Frequency Distributions		22	(4)
Let's Check Your Understanding		24	(1)
Our Model Answers		25	(1)
Cumulative Frequency Distribution		26	(1)
Some Final Thoughts About Frequency Distributions		27	(1)
Key Terms		28	(1)
Models and Self-instructional Exercises		28	(6)
Our Model		28	(2)
Our Model Answers		30	(1)
Now It's Your Turn		31	(2)
Our Model Answers		33	(1)
Words of Encouragement		34	(1)
3. The Distribution of Test Scores—The Perfect Body?		35	(12)
Kurtosis		35	(2)
Let's Check Your Understanding		37	(1)
Our Model Answers		37	(1)
Skewness		37	(4)
Let's Check Your Understanding		40	(1)
Our Model Answers		41	(1)
Some Final Thoughts About Distribution of Test Scores		41	(1)
Key Terms		41	(1)
Models and Self-instructional Exercises		42	(4)
Our Model		42	(1)
Our Model Answers		43	(1)
Now It's Your Turn		43	(2)
Our Model Answers		45	(1)
Words of Encouragement		46	(1)
4. Central Tendencies and Dispersion-Coming Together or Growing Apart		47	(24)
Central Tendencies—The Inner Core of the Normal Curve		47	(1)
The Mode		48	(2)
Let's Check Your Understanding		49	(1)
Our Model Answers		50	(1)
The Median		50	(3)
Let's Check Your Understanding		52	(1)
Our Model Answers		52	(1)
Medians and Modes for Grouped Frequency Data		53	(1)
The Mean		53	(4)
Let's Check Your Understanding		54	(1)
Our Model Answers		54	(1)
Now It's Your Turn		55	(1)
Our Model Answers		56	(1)
Some Final Points About Central Tendency		57	(1)
Dispersion—Not All Bodies Are the Same		57	(1)
Range		57	(1)
Deviation Scores		58	(1)
Variance		59	(1)
Standard Deviation		59	(3)
Let's Check Your Understanding		62	(1)
Our Model Answers		62	(1)
Means and Standard Deviations in the Real World		62	(1)
Key Terms		63	(1)
Models and Self-instructional Exercises		64	(5)
Our Model		64	(1)
Our Model Answers		65	(2)
Now It's Your Turn		67	(1)
Our Model Answers		68	(1)
Your New Best Friend—SPSS		69	(1)
Words of Encouragement		70	(1)
5. Standardized Scores—Po You Measure Up?		71	(22)
Percentiles—What They Mean in Measurement		71	(2)
Percentile Ranks for Grouped Data		73	(3)
Let's Check Your Understanding		75	(1)
Our Model Answers		75	(1)
Some Final Thoughts About Percentile Ranks		76	(1)
Z Scores		77	(1)
Why Transform a Raw Score to a Z Score?		77	(6)
Let's Check Your Understanding		81	(1)
Our Model Answers		81	(2)
Now It's Your Turn		83	(1)
Our Model Answers		83	(1)
Other Standard Scores		83	(2)
T Scores		84	(1)
IQ Scores		84	(1)
Key Terms		85	(1)
Models and Self-instructional Exercises		86	(4)
Our Model		86	(1)
Now It's Your Turn		87	(1)
Our Model Answers		88	(2)
Your New Best Friend—SPSS		90	(1)
Words of Encouragement		91	(2)
6. Norms and Criterion Scores—Keeping Up With the Joneses or Not		93	(8)
Criterion-Referenced Tests—Do You Know as Much as You Should?		93	(2)
Let's Check Your Understanding		94	(1)
Our Model Answers		94	(1)
Norm-Referenced Tests—Dying to Fit In		95	(3)
The Norm-Reference Group		95	(1)
The Fixed-Reference Group		96	(1)
Specific Group Norms		97	(1)
Let's Check Your Understanding		98	(1)
Our Model Answers		98	(1)
Key Terms		98	(1)
Models and Self-instructional Exercises		99	(1)
Our Model Answers		99	(1)
Words of Encouragement		100	(1)
7. Error Scores—The Truth, the Whole Truth, and Nothing but the Truth?		101	(10)
Test Theory		101	(2)
Let's Check Your Understanding		102	(1)
Our Model Answers		103	(1)
Test-Theory Assumptions		103	(3)
Let's Check Your Understanding		105	(1)
Our Model Answers		106	(1)
Key Terms		106	(1)
Models and Self-instructional. Exercises		107	(3)
Our Model		107	(1)
Our Model Answers		108	(1)
Now It's Your Turn		109	(1)
Our Model Answers		109	(1)
Words of Encouragement		110	(1)
8. Building a Strong Test—One the Big Bad Wolf Can't Blow Down		111	(10)
Let's Check Your Understanding		112	(1)
Our Model Answers		112	(1)
Item Difficulty		113	(1)
Some Final Thoughts About Item Difficulty		113	(2)
Let's Check Your Understanding		114	(1)
Our Model Answers		115	(1)
Item Discrimination		115	(3)
Let's Check Your Understanding		117	(1)
Our Model Answers		118	(1)
Key Terms		118	(1)
Models and Self-instructional Exercises		118	(2)
Our Model		118	(1)
Our Model Answers		119	(1)
Now It's Your Turn		119	(1)
Our Model Answers		120	(1)
Words of Encouragement		120	(1)
9. Reliability—The Sane Yesterday, Today, and Tomorrow		121	(20)
Let's Check Your Understanding		122	(1)
Our Model Answers		122	(1)
The Mathematical Foundation of Reliability		123	(1)
Let's Check Your Understanding		123	(1)
Our Model Answers		124	(1)
Types of Reliability Estimates		124	(8)
Test–Retest Reliability		124	(2)
Alternate Forms Reliability		126	(1)
Internal Consistency Reliability		127	(2)
Interrater Reliability		129	(1)
Let's Check Your Understanding		130	(1)
Our Model Answers		131	(1)
Standard Error of Measurement		132	(2)
Let's Check Your Understanding		133	(1)
Our Model Answers		134	(1)
Correlation Coefficients as Measures of Reliability		134	(1)
Some Final Thoughts About Reliability		135	(1)
Key Terms		135	(1)
Models and Self-instructional Exercises		135	(5)
Our Model		135	(1)
Our Model Answers		136	(1)
Now It's Your Turn		137	(2)
Our Model Answers		139	(1)
Words of Encouragement		140	(1)
10. Validity—What You See Is Not Always What You Get		141	(22)
Let's Check Your Understanding		142	(1)
Our Model Answers		143	(1)
Helping You Get What You See		143	(4)
Validation Groups		144	(1)
Criteria		144	(1)
Construct Underrepresentation		145	(1)
Construct-Irrelevant Variance		145	(1)
Let's Check Your Understanding		146	(1)
Our Model Answers		146	(1)
Sources of Validity Evidence		147	(6)
Evidence Based on Test Content		147	(1)
Evidence of Criterion-Related Validity		148	(2)
Evidence of Construct Validity		150	(1)
Let's Check Your Understanding		151	(1)
Our Model Answers		152	(1)
The Marriage of Reliability and Validity—Wedded Bliss		153	(1)
Interpreting the Validity of Tests-Intended and Unintended Consequences		154	(1)
Some Final Thoughts About Validity		154	(1)
Key Terms		155	(1)
Models and Self-instructional Exercises		155	(8)
Our Model		155	(2)
Our Model Answers		157	(1)
Now It's Your Turn		158	(2)
Our Model Answers		160	(2)
Words of Encouragement		162	(1)
11. The Perils and Pitfalls of Testing—Being Ethical		163	(4)
Your Own Competence		163	(1)
Rights of Those Being Tested		164	(1)
Potential Dangers		165	(1)
Ryan's Rights		166	(1)
Appendix		167	(4)
References		171	(2)
Index		173	(10)
About the Authors		183

Since I was a small child, I have always been a nurturer, someone who helps others. I patiently listen to their concerns, let them express their feelings, and, when appropriate, help them look at ways to feel better or behave differently. In its simplest form, I think of mentoring as a process of nurturing others. For me, it is using who I am and what I know to foster the personal and professional growth of graduate students. This is what I find most fulfilling about being a professor-the opportunity to develop meaningful individual relationships with my students with the primary goal being their academic and career success and fulfillment.

As I reflected on my almost 29-year tenure as a faculty member at Arizona State University, I realized that I have had the privilege of fostering the development of 50 doctoral graduates, as well as numerous master degree graduates. Currently, I am directing the dissertations of nine students. The students who enter our doctoral program in counseling psychology are amazing. They are unbelievably bright, articulate, and curious, and invariably kind-hearted. To be able to work with them is a privilege. I have never viewed being a teacher and mentor as a task or as "a job." Instead, I believe that these students have been gifts to me. As I have tried to enrich their lives and careers, they have enriched mine both personally and professionally. Mentoring is a reciprocal process, occurring in stages. Dr. Mary E. Stafford is a faculty member and internship coordinator in the School Psychology Program at University of Houston Clear Lake, where she is an Associate Professor. Dr. Stafford is editor of the International School Psychology Associations (ISPA) newsletter, the World*Go*Round. She teaches courses in personality assessment, child psychopathology, counseling children, and biological basis of behavior. Her research interests focus on at-risk children (especially, on influences on resilience among youth, on the effects of mobility among school-age children, and on socioeconomic, cultural, and language issues related to childrens achievement and adjustment in schools), on practice issues in schools internationally, and on ethics.

Dr. Stafford has a Ph.D. degree in Educational Psychology, with concentration in School Psychology, from the University of Texas at Austin. Prior to coming to UHCL in 2005, she was the Training Director in the School Psychology Program in the Division of Psychology in Education at Arizona State University. In her early career, she worked with children in public school and residential treatment center for emotionally handicapped settings as teacher, counselor, diagnostician, and school principal.