Official Site of The State of New Jersey
District Factor Groups for School Districts
The District Factor Groups (DFGs) were first developed in 1975 for the purpose of comparing students’ performance on statewide assessments across demographically similar school districts. The categories were updated twice, using the Census Bureau’s Decennial Census data from 1990 and 2000, respectively. However, the School Performance Reports no longer compare districts using this measure, and no updates have been made to the DFGs since the groupings were finalized in 2004. This webpage describes the origin and methodology used for the current groupings.
Historically, the DFGs played a significant role in determining the initial group of districts that were classified as Abbott districts. Subsequent to the Abbott IV court ruling, the groups were used to define the school districts on which Abbott v Burke parity remedy aid would be based. However, parity remedy aid is no longer included in the school funding formula. Since the DFGs were designed to provide an approximate measure of a community’s relative socioeconomic status (SES), the classification system provided a useful tool for examining student achievement and comparing similarly-situated school districts.
Summary of Updates from 1990 to 2000
In updating the DFGs using data from the 2000 Decennial Census, some changes were made to improve the methodology from 1990 while preserving the underlying meaning of the DFG classification system. After discussing the measure with representatives from school districts and experimenting with various methods, the DFGs were calculated using the following six variables that are closely related to SES:
- Percent of adults with no high school diploma
- Percent of adults with some college education
- Occupational status
- Unemployment rate
- Percent of individuals in poverty
- Median family income.
Unlike the model used to create the DFGs based on the 1990 census data, this model has omitted population density as a relevant variable. The same statistical method (principal components analysis) was used to determine districts’ relative SES. The method used to group the districts into DFG categories was also the same.
A number of methodological decisions were made to avoid classifying a school district in an inappropriate DFG category. First, communities in which there were fewer than 70 respondents to the Census questionnaire are omitted. Second, school districts in which more than half of the school-aged population is enrolled in non-public schools were not classified in a DFG. Both of these limitations are consistent with methods used in the previous DFG report. Third, school districts’ DFG ratings are adjusted to account for students who are part of sending-receiving relationships and, as such, live in other communities. This is the first time that such a method has been used. Note that since students’ characteristics are counted in the school district in which they attend school, non-operating school districts do not receive a DFG classification.
It has been suggested that the Decennial Census data may not accurately reflect the demographics of students enrolled in a district’s schools. Despite this concern, the census data are used for two reasons. First, experimentation with other data demonstrates there are no viable alternatives to the census data. Second, considerable research suggests that community characteristics, in addition to an individual’s characteristics, are relevant in terms of the impact of demographics on student performance.
Since the DFGs have not been updated with new data since the 2000 Census, caution should be exercised when comparing districts using these groupings.