There are two basic types of commands:
The third command, sc_dict(), may be used to explore the College Scorecard data dictionary.
sc_init()
Use sc_init() to start the command chain. The only real option is whether you want to use standard variable names (as they are found in IPEDS) or the new developer-friendly variable names developed for the Scorecard API. Unless you have good reason for doing so, I recommend using the default standard names. If you want to use the developer-friendly names, set dfvars = TRUE. Whichever you choose, you’re stuck with that option for the length of piped command chain; no switching from one type to another.
sc_get()
Use sc_get() as the last command in the chain. If you haven’t used sc_key to store your data.gov API key in the system environment, then you must supply your key as an argument.
The following commands are structured to behave like dplyr. They can be placed in any order in the piped command chain and each one relies (for the most part) on non-standard evaluation for its arguments. This means that you don’t have to quote variable names.
sc_select()
Use sc_select() to select the variables (columns) you want in your final dataframe. These variables do not have to be the same as those used to filter the data and are case insensitive. Separate the variable names with commas. The Scorecard API requires that most of the variables be prepended with their category. sc_select() uses a hash table to do this automatically for you so you do not have to know or include those (and in fact should not). This command is the only one of the subsetting commands that is required to pull data.
sc_filter()
Use sc_filter() to filter the rows you want in your final dataframe. Its main job is to convert idiomatic R code into the format required by the Scorecard API. Like sc_select(), sc_filter prepends variable categories automatically and variables are case insensitive. Like with dplyr::filter(), separate each filtering expression with a comma.There are a few points to note owing to the idiosyncracies of the Scorecard API. First, there are the conversions between R and the Scorecard, shown in the table below.
| Scorecard | R | R example | Conversion |
|---|---|---|---|
, |
c() |
sc_filter(stabbr == c('KY','TN')) |
school.state=KY,TN |
__not |
!= |
sc_filter(stabbr != 'KY') |
school.state__not=KY |
__range,..
|
#:# |
sc_filter(ccbasic==10:14) |
school.carnegie_basic__range=1..14 |
spaces (%20) |
’ ’ | sc_filter(instnm == 'New York') |
school.name=New%20York |
A few notes:
c(1,2,5:10)), it does not appear that Scorecard API can. You will either have to overselect and then filter the downloaded dataframe or list every value discretely.> or < symbols. This means that if you want to select a range of values above a certain threshold (e.g., enrollments above 10,000 students), you may have to give a range of from 10001 to an artifically large number. Same thing but reversed for values under a certain threshold.1:10 will convert to __range=1..10 and include both 1 and 10.sc_year()
All Scorecard variables except those in the root and school categories take a year option. Simply set the data year you want. For the latest data, you can either use sc_year("latest") or leave out sc_year() entirely, which will default to the latest data.
Two important points:
sc_zip()
Use sc_zip() to subset the sample to those institutions within a certain distance around a given zip code. Only one zip code may be given. The default is distance is 25 miles, but both the distance and metric (miles or kilometers) can be changed.
Users can search data elements in the College Scorecard data dictionary using sc_dict().
## simple search for 'state' in any part of the dictionary
sc_dict('stabbr')
#>
#> ---------------------------------------------------------------------
#> varname: stabbr source: IPEDS
#> ---------------------------------------------------------------------
#> DESCRIPTION:
#>
#> State postcode
#>
#> VALUES: NA
#>
#> CAN FILTER? Yes
#>
#> ---------------------------------------------------------------------
#> Printed information for 1 of out 1 variables.You can also search using regular expressions and limit the search to only one dictionary column. For example, the search below only looks for varnames starting with “st”:
## variable names starting with 'st'
sc_dict('^st', search_col = 'varname')
#>
#> ---------------------------------------------------------------------
#> varname: stabbr source: IPEDS
#> ---------------------------------------------------------------------
#> DESCRIPTION:
#>
#> State postcode
#>
#> VALUES: NA
#>
#> CAN FILTER? Yes
#>
#>
#> ---------------------------------------------------------------------
#> varname: st_fips source: IPEDS
#> ---------------------------------------------------------------------
#> DESCRIPTION:
#>
#> FIPS code for state
#>
#> VALUES:
#>
#> 1 = Alabama
#> 2 = Alaska
#> 4 = Arizona
#> 5 = Arkansas
#> 6 = California
#> 8 = Colorado
#> 9 = Connecticut
#> 10 = Delaware
#> 11 = District of Columbia
#> 12 = Florida
#> 13 = Georgia
#> 15 = Hawaii
#> 16 = Idaho
#> 17 = Illinois
#> 18 = Indiana
#> 19 = Iowa
#> 20 = Kansas
#> 21 = Kentucky
#> 22 = Louisiana
#> 23 = Maine
#> 24 = Maryland
#> 25 = Massachusetts
#> 26 = Michigan
#> 27 = Minnesota
#> 28 = Mississippi
#> 29 = Missouri
#> 30 = Montana
#> 31 = Nebraska
#> 32 = Nevada
#> 33 = New Hampshire
#> 34 = New Jersey
#> 35 = New Mexico
#> 36 = New York
#> 37 = North Carolina
#> 38 = North Dakota
#> 39 = Ohio
#> 40 = Oklahoma
#> 41 = Oregon
#> 42 = Pennsylvania
#> 44 = Rhode Island
#> 45 = South Carolina
#> 46 = South Dakota
#> 47 = Tennessee
#> 48 = Texas
#> 49 = Utah
#> 50 = Vermont
#> 51 = Virginia
#> 53 = Washington
#> 54 = West Virginia
#> 55 = Wisconsin
#> 56 = Wyoming
#> 60 = American Samoa
#> 64 = Federated States of Micronesia
#> 66 = Guam
#> 69 = Northern Mariana Islands
#> 70 = Palau
#> 72 = Puerto Rico
#> 78 = Virgin Islands
#>
#> CAN FILTER? Yes
#>
#> ---------------------------------------------------------------------
#> Printed information for 2 of out 2 variables.You can also return the data dictionary as a tibble. When storing the dictionary in an object, it may be useful to set print_off = TRUE so that the dictionary results don’t print to the console:
dict_df <- sc_dict('stabbr', print_off = TRUE, return_df = TRUE)
dict_df
#> # A tibble: 1 × 9
#> varname value label description source dev_friendly_name dev_category notes
#> <chr> <dbl> <chr> <chr> <chr> <chr> <chr> <chr>
#> 1 stabbr NA NA State postcode IPEDS state school NA
#> # … with 1 more variable: can_filter <dbl>If you want the full data dictionary, simply search for '.':
dict_df <- sc_dict('.', print_off = TRUE, return_df = TRUE)
dict_df
#> # A tibble: 3,383 × 9
#> varname value label description source dev_friendly_na… dev_category notes
#> <chr> <dbl> <chr> <chr> <chr> <chr> <chr> <chr>
#> 1 unitid NA NA Unit ID fo… IPEDS id root NA
#> 2 opeid NA NA 8-digit OP… IPEDS ope8_id root NA
#> 3 opeid6 NA NA 6-digit OP… IPEDS ope6_id root NA
#> 4 instnm NA NA Institutio… IPEDS name school NA
#> 5 city NA NA City IPEDS city school NA
#> 6 stabbr NA NA State post… IPEDS state school NA
#> 7 zip NA NA ZIP code IPEDS zip school NA
#> 8 accredage… NA NA Accreditor… FSA accreditor school NA
#> 9 insturl NA NA URL for in… IPEDS school_url school NA
#> 10 npcurl NA NA URL for in… IPEDS price_calculato… school NA
#> # … with 3,373 more rows, and 1 more variable: can_filter <dbl>