1. TYPES OF SCORES (PP. 117-121 IN HUTCHINSON; MERRELL & PLANTE; SECOND PART OF HAYNES AND PINDZOLA )

2. TYPES OF SCORES Item score Raw score Converted scores (See normal curve…)  percentile rank  Standard scores  z-scores  T-scores  Stanine  age-equivalent and grade-equivalent scores

3. Examples of item scores

4. More examples of item scores. Items scores together allow us to calculate raw score

5. TYPES OF SCORES Item score Raw score Converted scores (See normal curve…)  percentile rank  Standard scores (based on central tendency and distribution around measure of central tendency)  z-scores  T-scores  Stanine  age-equivalent and grade-equivalent scores

6. Converted scores all us to compare client’s score with that of the normative sample (sometimes called standardization sample)

8. PERCENTILE RANK Tells us what proportion of the norming population scored lower than the subject 99th percentile means out of 100 children 99 scored lower. 10th percentile means out of 100 children 10 scored lower.

10. 0 204 Example: 4:6 year olds 58 Measures of central tendency and variability…… Esp. mean and standard deviation To understand standard scores, you need to understand..

11. 0 204 Example: 4:6 year olds 58 To understand standard scores, you need to understand.. Standard deviation, in-class discussion (Standard deviation as the “average” distance of all deviations from the measure of central tendency)

12. In a normal (bell-shaped curve)  68% of the population will have a mean score between +/- 1 sd (e.g., b/w 85 and 115 on this sample IQ test)  95% of the population will have a mean score between +/- 2 sd (e.g., b/w 70 and 130 on this sample IQ test)

13. Note that standard deviation and percentile rank are related!

14. 0 Example: 4:6 year olds 58 Standard scores Raw score transformed to standard scores…. (3 types) 1001151308570 76954024

15. Raw score transformed to standard scores…. (We’ll consider three types of standard scores)

16. Transform to a distribution of Z-scores 1001151307085

17. Note that standard deviation and percentile rank AND z-scores are related!

18. Note that standard deviation and percentile rank are related. Standard scores like z- scores and t- scores say the same thing, just in a different language, as do stanines

19. TYPES OF SCORES: AGE/GRADE-EQUIVALENT SCORES (“DEVELOPMENTAL SCORES” LAWRENCE, 1992) E.g. Jack’s raw score: 59 age-equivalent score “5;2” Jack’s 59 is average (mean or median) raw score expected for child who is 5;2

20. (AGE EQUIVALENT SCORE, CONT.) Problems? Age equivalent score doesn’t consider:  Range of performance for that age  Someone whose chronological age is higher than their age-equivalent score may still be performing normally  e.g. child 6;2 with age-equivalent score of 5;2  Same score for kids of different ages may come from qualitatively different patterns of performance

21. (AGE EQUIVALENT SCORE, CONT.) Useful to:  Help parents understand extreme cases  Meet agency requirements BUT, rule of thumb:  Don’t use these scores!

22. AGE EQUIVALENT FUNCTION

23. Norm- referenced tests will give you table with converted scores, and will give you place to record them