Constructs a data frame of student-level records of First-Year Engineering (FYE) programs and conditions the data for later use as an input to the mice R package for multiple imputation. Sets up three variables as predictors (institution, race/ethnicity, and sex) and one variable to be estimated (program CIP code).
Arguments
- midfield_student
MIDFIELD
student
data table or equivalent with required variablesmcid
,race
, andsex.
- midfield_term
MIDFIELD
term
data table or equivalent with required variablesmcid
,institution
,term
, andcip6.
- ...
Not used for passing values; forces subsequent arguments to be referable only by name.
- fye_codes
Optional character vector of 6-digit CIP codes to identify FYE programs, default "140102". Codes must be 6-digit strings of numbers; regular expressions are prohibited. Non-engineering codes—those that do not start with 14—produce an error.
Value
A data frame in data.table
format conditioned for
later use as an input to the mice R package for multiple imputation. The
data frame comprises one row for every FYE student, first-term and
migrator. Grouping structures are not preserved. The columns returned
are:
mcid
Character, anonymized student identifier. Returned as-is.
race
Factor, race/ethnicity as self-reported by the student. An imputation predictor variable.
sex
Factor, sex as self-reported by the student. An imputation predictor variable.
institution
Factor, anonymized institution name. An imputation predictor variable.
proxy
Factor, 6-digit CIP code of a student's known, post-FYE engineering program or NA representing missing values to be imputed.
Details
At some US institutions, engineering students are required to complete a First-Year Engineering (FYE) program as a prerequisite for declaring an engineering major. Administratively, degree-granting engineering programs such as Electrical Engineering or Mechanical Engineering treat their incoming post-FYE students as their "starting" cohorts. However, when computing a metric that requires a count of starters—graduation rate, for example—FYE records must be treated with special care to avoid a miscount.
To illustrate the potential for miscounting starters, suppose we wish to calculate a Mechanical Engineering (ME) graduation rate. Students starting in ME constitute the starting pool and the fraction of that pool graduating in ME is the graduation rate. At FYE institutions, an ME program would typically define their starting pool as the post-FYE cohort entering their program. This may be the best information available, but it invariably undercounts starters by failing to account for FYE students who do not transition (post-FYE) to degree-granting engineering programs—students who may have left the institution or switched to non-engineering majors. In either case, in the absence of the FYE requirement, some of these students would have been ME starters. By neglecting these students, the count of ME starters is artificially low resulting in an ME graduation rate that is artificially high. The same is true for every degree-granting engineering discipline in an FYE institution.
Therefore, to avoid miscounting starters at FYE institutions, we have to estimate an "FYE proxy", that is, the 6-digit CIP codes of the degree-granting engineering programs that FYE students would have declared had they not been required to enroll in FYE. The purpose of `prep_fye_mice()“ is to prepare the data for making that estimation.
After running prep_fye_mice()
but before running mice()
, one can edit
variables or add variables to create a custom set of predictors. The mice
package expects all predictors and the proxy variables to be factors. Do not
delete the institution variable because it ensures that a student's imputed
program is available at their institution.
In addition, ensure that the only missing values are in the proxy column. Other variables are expected to be complete (no NA values). A value of "unknown" in a predictor column, e.g., race/ethnicity or sex, is an acceptable value, not missing data. Observations with missing or unknown values in the ID or institution columns (if any) should be removed.
Method
The function extracts all terms for all FYE students,
including those who migrate to enter Engineering after their first term,
and identifies the first post-FYE program in which they enroll, if any.
This treatment yields two possible outcomes for values returned in the
proxy
column:
The student completes FYE and enrolls in an engineering major. For this outcome, we know that at the student's first opportunity, they enrolled in an engineering program of their choosing. The CIP code of that program is returned as the student's FYE proxy.
The student does not enroll post-FYE in an engineering major. Such students have no further records in the database or switched from Engineering to another program. For this outcome, the data provide no information regarding what engineering program the student would have declared originally had the institution not required them to enroll in FYE. For these students a proxy value of NA is returned. These are the data treated as missing values to be imputed by
mice()
.
In cases where students enter FYE, change programs, and re-enter FYE, only the first group of FYE terms is considered. Any programs before FYE are ignored.
The resulting data frame is ready for use as input for the mice package,
with all variables except mcid
returned as factors.
Examples
# Using toy data
prep_fye_mice(toy_student, toy_term)
#> mcid race sex institution proxy
#> <char> <fctr> <fctr> <fctr> <fctr>
#> 1: MID26060301 Asian Female Institution C <NA>
#> 2: MID25995980 Latine Female Institution C <NA>
#> 3: MID25997636 Latine Female Institution C <NA>
#> 4: MID26086310 Latine Female Institution C <NA>
#> 5: MID26000057 White Female Institution C <NA>
#> 6: MID26614720 Asian Male Institution J <NA>
#> 7: MID26593796 White Male Institution J <NA>
#> 8: MID25848589 White Male Institution M 143501
#> 9: MID25846316 White Male Institution M 143501
#> 10: MID25847220 White Male Institution M 143501
#> 11: MID25828870 White Male Institution M 149999
# Other columns, if any, are dropped
colnames(toy_student)
#> [1] "mcid" "institution" "race" "sex"
colnames(prep_fye_mice(toy_student, toy_term))
#> [1] "mcid" "race" "sex" "institution" "proxy"
# Optional argument permits multiple CIP codes for FYE
prep_fye_mice(midfield_student = toy_student,
midfield_term =toy_term,
fye_codes = c("140101", "140102"))
#> mcid race sex institution proxy
#> <char> <fctr> <fctr> <fctr> <fctr>
#> 1: MID25977316 White Male Institution B <NA>
#> 2: MID26060301 Asian Female Institution C <NA>
#> 3: MID25995980 Latine Female Institution C <NA>
#> 4: MID25997636 Latine Female Institution C <NA>
#> 5: MID26086310 Latine Female Institution C <NA>
#> 6: MID26000057 White Female Institution C <NA>
#> 7: MID26614720 Asian Male Institution J <NA>
#> 8: MID26593796 White Male Institution J <NA>
#> 9: MID25848589 White Male Institution M 143501
#> 10: MID25846316 White Male Institution M 143501
#> 11: MID25847220 White Male Institution M 143501
#> 12: MID25828870 White Male Institution M 149999