2 paragraph comment

profilefsuarez420
Chapter17.pdf

Educational Assessment of Students Eighth Edition

Chapter 17 Interpreting Norm- Referenced Scores

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Key Concepts (1 of 2)

17.1 A referencing framework is a structure used to compare a student’s performance to some-thing external to the assessment in order to interpret performance. A norm-referencing framework interprets a student’s assessment performance by comparing it to the performance of a well-defined group of other students who have taken the same assessment. A criterion-referencing framework interprets a student’s performance according to the kinds of performances a student can do in a domain. A standards-referenced framework combines elements of both. Test publishers may provide norm-referenced scores based on information from several different norm groups. Use normative information to describe student strengths, weak-nesses, and progress.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Key Concepts (2 of 2)

17.2 Different types of norm-referenced scores are constructed to serve different purposes. The percentile rank tells the percentage of the students in a norm group who have scored lower than the raw score in question. A linear standard score tells how far a raw score is from the mean of the norm group, expressing the distance in standard deviation units.

17.3 A normal distribution is a mathematical model (an equation) based on the mean and standard deviation of a set of scores. Normalized standard scores are based on transforming raw scores on an assessment to make them fit a normal distribution. Developmental and educational growth scales are norm- referenced scores that can be used to chart educational development or progress. An extended normalized standard score tells the location of a raw score on a scale that is anchored to a lower grade reference group. A grade- equivalent score tells the grade level at which a raw score is average.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Norm- versus Criterion-Referencing

• A norm-referencing framework interprets a student’s assessment performance by comparing it to the performance of a well-defined group of other students who have taken the same assessment.

• A criterion-referencing framework interprets a student’s performance according to the kinds of performances a student can do in a domain.

• A standards-referenced framework combines elements of both.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Norm Groups

• Local norm group: students in the same grade in the same school district

– Schools/districts should have scores – Publishers may offer scores

• National norm group: intended to be representative of students in the country

– Test publishers use different norming procedures

• Special norm group

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

School Averages Norms

• School averages norms: ranked tabulation of the average (mean) score from each school building in a national sample of schools

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Guidelines for Using Publishers’ Norms

• Make sure the norm group is: – Relevant – Representative – Recent

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Percentile Rank

• The percentile rank tells the percentage of the students in a norm group who have scored lower than the raw score in question.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Percentile Ranks: Advantages

• Easily understood.

• Clearly reflect norm-referencing.

• Permit a person’s performance to be compared to a variety of norm groups.

• Can be used to compare a student’s relative standing in each of several achievement or ability areas.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Percentile Ranks: Limitations

• Can be confused with percentage correct scores.

• Can be confused with some other types of two-digit derived scores.

• Do not form an equal-interval scale.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Linear Standard Score

• A linear standard score tells how far a raw score is from the mean of the norm group, expressing the distance in standard deviation units.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Z Scores

• Communicate students’ norm-referenced achievement expressed as a distance away from the mean.

– if Z = −1.5, the student’s score is 1.5 standard deviations below the average score.

• Can be used for norm-referenced comparison of raw scores with different metrics

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

SS Scores

• Tells the location of a raw score in a distribution having a mean of 50 and a standard deviation of 10.

– Transformation of z score – Example: If Z = −1.5, SS = 35

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Normalized Standard Scores

• A normal distribution is a mathematical model (an equation) based on the mean and standard deviation of a set of scores.

– Normal curves are smooth, continuous, symmetrical, and bell shaped

• Normalized standard scores are based on transforming raw scores on an assessment to make them fit a normal distribution.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Normalized z -Scores

• z-scores that have percentile ranks corresponding to what we would expect in a normal distribution

Raw Score Percentile rank

Normalized standard (zn)

Linear standard (z)

36 98 2.05 2.43 33 96 1.75 1.64 15 4 −1.75 −3.09 14 2 −2.05 −3.36

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Normalized T-scores

• Tell the location of a raw score in a normal distribution having a mean of 50 and a standard deviation of 10.

– Example: Joey’s T-score is 40, which means he is one standard deviation below the mean of the norm group, and his percentile rank is approximately 16.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Deviation IQ Scores

• Tells the location of a raw score in a normal distribution having a mean of 100 and a standard deviation of 15 or 16.

– Example: Meghan has DIQ = 116, which means she has scored one standard deviation above the mean of her age group and the percentile rank of her score is 84.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Stanines

• Tells the location of a raw score in a specific segment of a normal distribution.

– Example: Blake’s stanine on the spelling subtest of the standardized test was 3, which means that his raw score was in the lower 20% of the norm group. Specifically, his percentile rank was between 11 and 22.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

SAT-Scores

• Historically, a normalized standard score from a distribution that has a mean of 500 and a standard deviation of 100.

• The SAT program no longer uses this computation, but the current scores on the 200-800 scale can be compared across administrations.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Normal Curve Equivalents

• NCE scores are normalized standard scores with a mean of 50 and a standard deviation of 21.06.

• Primary value is evaluating gains from various educational programs that use different publishers’ tests

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Developmental and Educational Growth Scales

• Developmental and educational growth scales are norm- referenced scores that can be used to chart educational development or progress.

– Extended normalized standard score scale – Grade-equivalent score scale

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Extended Normalized Standard Score

• An extended normalized standard score tells the location of a raw score on a scale that is anchored to a lower grade reference group.

– Based on extended z scale Or – Based on item response theory

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Grade-Equivalent Score

• A grade-equivalent score tells the grade level at which a raw score is average.

– Useful for reporting educational development. – Provided by test publisher.

▪ GE is the median score (sometimes mean score) in each grade’s norm group.

▪ A third grader’s GE score of 5.7 on a mathematics test covering third-grade content does not mean that this student should be placed in fifth-grade math. Rather, it means that he scored the same as the average 5th grader (7th month) on the third-grade test.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Things to Keep in Mind When Interpreting Grade Equivalents (1 of 2)

• In some subject areas, students’ performance drops over the summer months.

• The meaning of grade-equivalent scores for a subject depends very much on the subject matter.

• Grade-equivalent scores do not necessarily indicate mastery of the material.

• The more closely the test items match the material emphasized in the classroom before the test was administered, the more likely the students will score well above grade level.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Things to Keep in Mind When Interpreting Grade Equivalents (2 of 2)

• Grade equivalents from different tests cannot be interchanged.

• Grade equivalents for different subjects cannot be compared.

• Grade equivalents do not indicate “normal” growth.

• The grade-equivalent score scale does not have a one- to-one correspondence with the number of questions a student answers correctly on a test.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Guidelines for Score Interpretation

• Look for patterns in scores.

• Seek explanations for the patterns.

• Don’t expect many surprises.

• Don’t overinterpret small differences.

• Use evidence from other assessments to clarify interpretations.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Typical Misunderstandings (1 of 2)

• The grade-equivalent score tells which grade the student should be in.

– They Do Not.

• The percentile rank and percent-correct scores mean the same thing. – They Do Not.

• The percentile rank norm group consists of only the students in a particular classroom.

– It Does Not.

• “Average” is the standard to beat. – It Is Not.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Typical Misunderstandings (2 of 2)

• Small changes in percentile ranks over time are meaningful.

– They Are Not.

• Percent-correct scores below 70 are failing. – They Are (Usually) Not.

• If you get a perfect score, your percentile rank must be 99.

– It May Not Be.

Copyright © 2019, 2015, 2012 Pearson Education, Inc. All Rights Reserved

Copyright

  • Educational Assessment of Students
  • Key Concepts (1 of 2)
  • Key Concepts (2 of 2)
  • Norm- versus Criterion-Referencing
  • Norm Groups
  • School Averages Norms
  • Guidelines for Using Publishers’ Norms
  • Percentile Rank
  • Percentile Ranks: Advantages
  • Percentile Ranks: Limitations
  • Linear Standard Score
  • Z Scores
  • S S Scores
  • Normalized Standard Scores
  • Normalized z -Scores
  • Normalized T - s c o r e s
  • Deviation I Q Scores
  • Stanines
  • S A T-Scores
  • Normal Curve Equivalents
  • Developmental and Educational Growth Scales
  • Extended Normalized Standard Score
  • Grade-Equivalent Score
  • Things to Keep in Mind When Interpreting Grade Equivalents (1 of 2)
  • Things to Keep in Mind When Interpreting Grade Equivalents (2 of 2)
  • Guidelines for Score Interpretation
  • Typical Misunderstandings (1 of 2)
  • Typical Misunderstandings (2 of 2)
  • Copyright