Page 52 - The Importance of Common Metrics for Advacing Social Science Theory and Research

The Importance of Common Metrics for Advancing Social Science Theory and Research: A Workshop Summary
http://www.nap.edu/catalog/13034.html

40 THE IMPORTANCE OF COMMON METRICS

completion rates differ so much from one another is that they differ with
respect to what they are trying to accomplish.
Economists or business leaders may be interested in characterizing the
level of human capital in a population or in a region. For this purpose,
the timing of high school completion (how long ago or at what age people
completed high school) is not important. According to Warren, dropout
status or completion rates computed from cross-sectional sample surveys
are best suited to describing levels of human capital in a population. Be-
cause the goal is to describe the share of all individuals who have obtained
a credential, it is important to use data that include people who may have
gotten those credentials from any number of places: public schools, private
schools, GED programs, community colleges, adult education programs,
prisons, or the Internet. Administrative data alone are not sufficient for
measuring the percentage of people in the population who fall into a par-
ticular status group.
Education policy makers may instead focus on quantifying school per-
formance in evaluating schools (within a school district or against national
standards) with respect to their “holding power.” How well do schools
move young people from the first day of high school through to successful
high school completion?
Both the timing of high school completion and the manner in which
students complete high school are necessary factors to consider. Schools
may be deemed successful at moving young people through to completion
of high school only if they grant regular high school diplomas within four
years.
Researchers may be more interested in characterizing students’ experi-
ences in navigating through educational institutions, or in predicting the
likelihood of dropping out, or in modeling the consequences of dropping
out. These measures are designed to describe characteristics of students or
groups of students rather than a school’s attributes.

Technical Differences in Measures
Another reason that high school dropout and completion rates differ
involves technical differences in how they are constructed. This is true even
when comparing measures that are intended for the same purpose. All high
school completion and dropout rates are based on a ratio with a numera-
tor and a denominator: the numerator is the number of high school com-
pleters or dropouts, and the denominator is the number of people at risk of
completing or dropping out. But even when measuring the same concept,
there are frequently differences with respect to who has been counted as a
completer or a dropout in the numerator and who is at risk of being in one
of those statuses in the denominator.

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