The IPEDS Unit of Observation Challenge
The challenges posed by the structure of IPEDS data can best be illustrated through concrete examples. One of the clearest is Rutgers University—which consists of three campuses—Camden, New Brunswick, and Newark—but is a single Title IV institution. This means:
Rutgers does not undergo separate accreditation processes for each campus.
It does not sign separate Title IV program participation agreements (PPAs) with the federal government on behalf of each campus.
For purposes of accreditation and Title IV financial aid, Rutgers is treated as a single university.
However, within IPEDS data, Rutgers appears as three separate observations, one for each campus. This highlights a broader issue: IPEDS observations can represent different entities. They may reflect
An entire Title IV institution,
A single campus within a multi-campus Title IV institution,
Or an administrative office that supports multiple Title IV institutions.
To complicate matters further, multi-campus institutions or administrative offices may change their reporting patterns over time, adding another layer of complexity for researchers working with longitudinal data.
Delving Deeper Into the Rutgers Example
Rutgers illustrates the complexities that follow changed reporting patterns. From fiscal years 2004 through 2023, Rutgers consistently reported enrollment data separately for its Camden, New Brunswick, and Newark campuses.
However, its financial reporting varied:
In FY2004 and FY2014–FY2023, Rutgers reported financial data separately by campus.
But during the FY2005–FY2013 period, all financial data was reported only within the New Brunswick campus observation.
This inconsistency can lead to misleading results if not properly addressed. For example, if one were to simply load IPEDS data and calculate net tuition revenue (NTR) per student by dividing NTR by enrollment, the resulting figures for Rutgers campuses—provided in the table at the end of this post—would contain three problems.
Missing Data: No per-student NTR values are available for Camden and Newark for FY2005-FY2013.
Flawed estimates: The per-student NTR figures for New Brunswick for FY2005-FY2013 are inaccurate because they divide combined net tuition revenue for all three campuses by enrollment for only the New Brunswick campus.
Inconsistent units of observation: The campus-specific Rutgers data for FY2004 and FY2014-FY2023 contains a different unit of observation than used for other IPEDS observations. Some multi-campus Title IV institutions report all enrollment and financial data within a single IPEDS observation.
Rutgers is just one example that illustrates the complexities of IPEDS reporting. Other examples would present different variations of the unit of observation challenge, each with its own implications for data analysis.
Available Literature
My understanding of this issue was significantly shaped by a handbook chapter and a journal article authored by Ozan Jaquette and Edna Parra. Their work persuasively argues that researchers should collapse IPEDS data to the level of a Title IV institution. This collapsing process involves summing data across different IPEDS observation that correspond to the same Title IV institution.
Building on the foundation laid by Jaquette and Parra, I introduced methods—in my own journal article—for handling IPEDS observations that pertain to administrative offices supporting multiple Title IV institutions. The methods proposed in these articles are implemented in the NTRN data sets available for download.
Rutgers Data
The per-student NTR figures for Rutgers University in these datasets are reported in the last column of the below table. The problems previously noted—missing data, flawed estimates, and inconsistent units of observation—are no longer present.
| Fiscal Year | Rutgers-Camden | Rutgers-Newark | Rutgers-New Brunswick | Rutgers (All) |
|---|---|---|---|---|
| 2004 | $9,500 | $9,500 | $9,500 | $9,500 |
| 2005 | . | . | $14,164 | $10,283 |
| 2006 | . | . | $15,097 | $11,020 |
| 2007 | . | . | $15,953 | $11,666 |
| 2008 | . | . | $17,204 | $12,517 |
| 2009 | . | . | $18,409 | $13,331 |
| 2010 | . | . | $18,651 | $13,085 |
| 2011 | . | . | $19,782 | $13,936 |
| 2012 | . | . | $20,492 | $14,600 |
| 2013 | . | . | $21,062 | $14,985 |
| 2014 | $15,742 | $16,893 | $15,812 | $15,975 |
| 2015 | $15,882 | $17,842 | $16,591 | $16,723 |
| 2016 | $16,587 | $22,453 | $16,017 | $17,102 |
| 2017 | $14,819 | $19,900 | $15,037 | $15,822 |
| 2018 | $14,753 | $20,292 | $15,906 | $16,541 |
| 2019 | $14,332 | $21,248 | $16,576 | $17,180 |
| 2020 | $14,369 | $22,437 | $17,114 | $17,788 |
| 2021 | $15,307 | $21,598 | $16,836 | $17,527 |
| 2022 | $16,006 | $23,477 | $17,307 | $18,199 |
| 2023 | $15,792 | $22,886 | $17,142 | $17,888 |