Using Normal Curve Equivalents to

Determine Strengths and Weaknesses

What is a normal curve equivalent?

A normal curve equivalent (NCE) is a norm-referenced, equal-interval, derived, standard test score that ranges from a low of 1 to a high of 99. For each subtest and grade level, the mean national NCE is 50.

 

How are NCE's interpreted?

NCEs and percentiles have the same range 1-99. NCEs and percentiles match at 3 points- 1, 50, and 99. NCEs and percentiles do not match at anyother points. Because NCEs are based on an equal-interval scale, a gain of five NCEs represents exactly the same amount of improvement in achievement for students at the extreme lower end or extreme upper end of the scale as it does for average students. Note that percentiles do not have this characteristic.For each grade level and subtest, an NCE of 50 represents average performance compared to the national group. NCEs may be used to show growth a student or a group of students makes. A student who earns an NCE of 47 at the end of grade 3 and an NCE of 47 at the end of grade 4 has gained one year. Had the same student earned an NCE of 48 at the end of grade 4, we would know that the student gained more than one year from third grade to fourth grade. On the other hand, if the same student earned an NCE of 45 in grade 4, we would know that the student gained less than one year from the third to the fourth grade.

 

How are NCE's used?

Because NCEs are equal-interval scores, they may be averaged and used in mathematical calculations. Frequently, NCEs are used to show the grow thmade by a student or by groups of students.

 

On which reports are NCE's found?

NCEs for individual students are found on the reports entitled, Individual Profile Report and Class Record Sheet. Mean NCEs (MNCEs) for a teacher's class are provided on the Class Record Sheet. MNCEs for a grade level within a school or district are found on the Class Summary Report. Three-year average MCNEs and annual MCNEs were reported for schools and districts in the 1999-00 and 2000-01 Report Cards that were issued by the Tennessee Department of Education.

 

Step One:

Using the Class Record Sheet and the TCAP Class Summary Reports, record the MCNEs for your class and/or subject areas. Be sure to match the year, grade level, and subtest as you record MNCEs.

Step Two:

Use the 3-year Average Mean Normal Curve Equivalents on the TCAP for 2002 to compute and compare your group to the state wide three-year average MNCEs. You can find three-year data in the Report Card 2002 issued by the state.

Step Three:

Complete the Sheet "Interpreting Your Group's NCEs" to find your areas of needs and strengths.

 

Move on to Lesson 2- Percentiles

 

 

Home, Goals, Lesson1, MNCE, Lesson 2, MDNP, Lesson 3, OPI, Links