Assessment in counseling chapter 2

∗ Individual’s score is compared to performance of others who have taken the same instrument norming group∗ Example: personality inventory ∗ Evaluating the norming group ∗ size ∗ samplin

Basic Assessment

Principles

Chapter 2

∗ Individual’s score is compared to performance of others who have taken the same instrument (norming group)

∗ Example: personality inventory

∗ Evaluating the norming group

∗ size

∗ sampling

∗ representation

Norm-Referenced Instruments

∗ Individual’s performance is compared to specific

criterion or standard

∗ Example: third-grade spelling test

∗ How are standards determined?

∗ common practice

∗ professional organizations or experts

∗ empirically-determined

Criterion-Referenced Instruments

Robert 72 Miles 96 Jason 68 Whitney 79

Alice 82 Paul 59 Pedro 86 Jane 85

Beth 94 John 82 Kelly 92 Michael 81

Amy 77 Kevin 85 Justin 72 Rebecca 88

Porter 62 Ling 98 Sherry 67 Maria 86

Norm-Referenced: Sample Scores

X 50-59 60-69 70-79 80-89 90-100

Frequency Distribution

Frequency Polygon

Histogram

Measures of Central Tendency

∗ Mode – most frequent score

∗ Median – evenly divides scores into two halves (50% of scores fall above, 50% fall below)

∗ Mean – arithmetic average of the scores

∗ Formula:

N X

Measures of Central Tendency

Measures of Variability

∗ Range – highest score minus lowest score

∗ Variance – sum of squared deviations from the mean

∗ Standard Deviation – square root of variance

Normal Distribution

Skewed Distribution

Interpreting Percentiles

∗ Units are not equal

∗ Useful for providing information about relative position in normative sample

∗ Not useful for indicating amount of difference between scores

Interpreting Percentiles

Types of Standard Scores

∗ Mean = 50

∗ Standard deviation = 10

T Scores

Stanines

Standard Scores: Summary

∗ Possible problematic scores

∗ Age-equivalent scores

∗ Grade-equivalent scores

∗ Problematic because:

∗ These scores do not reflect precise performance on an instrument

∗ Learning does not always occur in equal developmental levels

∗ Instruments vary in scoring

Additional Converted Scores

∗ Adequacy of norming group depends on:

∗ Clients being assessed

∗ Purpose of the assessment

∗ How information will be used

∗ Examine methods used for selecting group

∗ Examine characteristics of norming group

Evaluating the Norming Group

∗ Methods for selecting norming group:

∗ Simple random sample

∗ Stratified sample

∗ Cluster sample

Sampling Methods

∗ Is the norming group appropriate for use with this client?

Norming Group Characteristics