brewdata: Function that Converts Grad Cafe Results Data into Usable...

Description Usage Arguments Value Note Author(s) References See Also Examples

View source: R/brewdata.R

Description

The brewdata method queries the GradCafe Results Search page for application decision data. It then calls the parseResults function to breakdown the text from "Decision & Date" into values useful for exploring admissions decisions.

Usage

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brewdata(years = 2015, term = "F", degree = "phd", focus = "statistics", 
	resolution = 10, map=FALSE)

Arguments

years

years specifies which years of data to include in the dataset. The year specifies the time at which an applicant would start school not when he or she applied. So, if someone applied for fall 2014 and was accepted in December 2013 and that person was also thoughtful enough to post his or her metrics on the Grad Cafe's Results Search page, then that record would appear if 2014 is part of the years searched. The four digit year (e.g. 2010, 2012, 1999, etc.) is the only acceptable date format. Inputs may be a single value or a list such as 2010:2015 or c(2011,2013,2015). The default is 2015.

term

term indicates which term an applicant would begin graduate study. There are only two acceptable values for this parameter: 'F' and 'S'. 'F' narrows the search to fall matriculations only. 'S' narrows the search to include only the spring term. Users may choose only one value. The default is 'F'.

degree

degree determines whether results should be for masters or phd programs. Users must specify exactly one and enclose the value in quotes. 'masters' or 'phd' are the only acceptable values for this field. The default is 'phd'.

focus

focus specifies the program. Any term that returns results on the Grad Cafe is acceptable, but brewdata was tuned using 'statistics' or 'biostatistics'. School name mappings could be quite poor for any value other than these two. If you choose a value besides 'statistics' or 'biostatistics', it is strongly suggested to check the school name mapping by setting map=TRUE. The default value is 'statistics'.

resolution

resolution is related to the school name parsing algorithm. This variable controls the precision required before an original name is replaced with the best standardized equivalent. Therefore, very low values (between 0-5) are cautious selections leading to fewer mis-matches, but more sparse results. Medium range values (8-12) lead to surprisingly accurate replacements when the mother processing stages fail. One might expect a few mis-matched name replacements, but the number of errors should be fairly low. Finally, large values (more than 20) practically guarantee that a school name which is not in our standard dictionary will be replaced with something. Be weary of such large selections; the potential for many mis-matched replacements is high. For the test set, the bulk of the nearest matchs were within 10 units of the original value. Almost none were larger than 30. The default value is 10.

map

map is a variable controlling whether or not the original school names are included in the data frame returned by brewdata(). If map=TRUE, then the returned data includes the parsed names as well as the original. The default value is map=FALSE.

Value

brewdata returns a data frame of the parsed Grade Cafe Results data. The data frame includes the following attributes:

school_name

is the closest standardized name matching the name entered at the Grad Cafe. brewdata normalizes the names reported on the website to enable aggregate analysis. See the parse_names parameter description above for more details on the parsing methods.

original_name

is the original name of the university reported to the Grad Cafe. If map=TRUE, then brewdata includes a column showing the names reported on the website alongside the normalized names assigned by brewdata. This column is excluded by default.

decision

denotes a university's decision on an application. Possible decisions are accepted ('A'), wait listed ('W'), rejected ('R'), interview ('I') or other ('O').

status

denotes an applicant's immigration status. This field is reported directly from the Grad Cafe. Per the website definitions, possible status values are American ('A'), International with a US degree ('U'), International without US degree ('I'), other ('O'), or unknown ('?').

gpa

is the self-reported grade point average.

gre_v

is the self-reported GRE verbal section score

gre_q

is the self-reported GRE quantitative section score

gre_aw

is the self-reported GRE analytical writing score

v_pct

is the percent of verbal section scores below an applicant's self-reported score. Weighted numeric scores are converted to percentile scores using tables 1A and 1B on page 22 of the GRE score guide. Source: https://www.ets.org/s/gre/pdf/gre_guide.pdf.

q_pct

is the percent of quantitative section scores below an applicant's self-reported score. Weighted numeric scores are converted to percentile scores using tables 1A and 1B on page 22 of the GRE score guide. Source: https://www.ets.org/s/gre/pdf/gre_guide.pdf.

aw_pct

is the percent of analytical writing section scores below an applicant's self-reported score. Weighted numeric scores are converted to percentile scores using tables 1A and 1B on page 22 of the GRE score guide. Source: https://www.ets.org/s/gre/pdf/gre_guide.pdf.

month

is the month of the date that an admission decision was made–not the date an applicant uploaded the result to the Grad Cafe.

day

is the day of the date that an admission decision was made–not the date an applicant uploaded the result to the Grad Cafe.

year

is the day of the date that an admission decision was made–not the date an applicant uploaded the result to the Grad Cafe.

Note

Several specialty university departments are mapped to their parent institutions. For example, Booth, Wharton, and Teachers College are mapped to the University of Chicago, University of Pennsylvania, and Columbia University, respectively. If you are interested in results for such schools, set map=TRUE and use grep() on the original_name column to locate rows of data with the desired department. See below for an example.

Author(s)

Nathan Welch <nathan.welch@me.com>

References

Grad Cafe: http://www.thegradcafe.com GRE Score Guide: https://www.ets.org/s/gre/pdf/gre_guide.pdf

See Also

findScorePercentile, parseResults, parseSchools, translateScore, getGradCafeData, getMaxPages

Examples

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#Get data for fall 2015 PhD statistics admission decisions
one_yr_data = brewdata( years=2014 )
head( one_yr_data )

### Remaining examples commented out to satisfy CRAN policies ###
#Get several years of data
#yrs=2014:2015
#multi_yr_data = brewdata( years=yrs ); head( multi_yr_data )
#results_by_school = split(multi_yr_data[,-1],multi_yr_data$school_name)

#Find 2014 results for Chicago Booth
#f14 = brewdata( years=2014, map=TRUE )
#booth = f14[ grepl( "booth", tolower( f14$original_name ) ), ]
#booth

#Continuing with the f15 & school data, let's analyze results from a particular
#school, e.g. University of Washington 
#uw = f15_by_school$'univ washington'; uw	#show all UW decisions
#uw_stats = uw[ uw$gre_v!=0 & uw$gre_q!=0, ]	#UW decisions with GRE stats
#plot( uw_stats$gpa, uw_stats$gre_q, xlab="Undergrad GPA", ylab="GRE Quant Score",
#	main="University of Washington GPA vs GRE Quant", pch=NA  )
#col_key = c('darkgreen','gold','red','black','darkgrey')
#lab = factor( uw_stats$decision, levels=c('A','W','R','I','N') )
#text( uw_stats$gpa, uw_stats$gre_q, label=lab, col=col_key[lab], cex=0.85 )


#Plot the last two years of Berkeley's GPA/GRE Quant decision trends
#yrs=2013:2014
#data = brewdata( years=yrs ); head( data )
#berk = split(data[,-1],data$school_name)$'univ california berkeley'
#berk_stats = berk[ berk$gre_v!=0 & berk$gre_q!=0, ]
#plot( berk_stats$gpa, berk_stats$gre_q, xlab="Undergrad GPA", ylab="GRE Quant Score",
#	main="Berkeley GPA vs GRE Quant Fall 2010-2015", pch=NA  )
#col_key = c('darkgreen','gold','red','black','darkgrey')
#lab = factor( berk_stats$decision, levels=c('A','W','R','I','N') )
#points( jitter( berk_stats$gpa ), jitter( berk_stats$gre_q ), 
#	col=col_key[lab], pch=20)
#lgd=c("Accepted", "Wait listed", "Rejected", "Interview", "Not Reported" )
#legend( "bottomleft", legend=lgd, col=col_key, pch=20, bty="n", cex=0.75 )


#Plot several years of results of Duke results using the same data from the 
#Berkeley download.
#library( scatterplot3d )
#library( rgl )
#duke = split(data[,-1],data$school_name)$'duke univ'
#duke_stats = duke[ duke$gre_v!=0 & duke$gre_q!=0, ]
#col_key = c('darkgreen','gold','red','black','darkgrey')
#lab = factor( duke_stats$decision, levels=c('A','W','R','I','N') )
#scatterplot3d( duke_stats$gpa, duke_stats$gre_q, duke_stats$gre_v,
#	xlab="Undergrad GPA", ylab="GRE Quant Score", zlab="GRE Verbal Score",
#	main="Duke GPA vs GRE Quant vs GRE Verbal Fall 2010-2015", pch=20,
#	color=col_key[lab]  )
#plot3d( duke_stats$gpa, duke_stats$gre_q, duke_stats$gre_v,
#	xlab="Undergrad GPA", ylab="GRE Quant Score", zlab="GRE Verbal Score",
#	main="Duke GPA vs GRE Quant vs GRE Verbal Fall 2010-2015", pch=20,
#	col=col_key[lab]  )
	

brewdata documentation built on May 29, 2017, 4:28 p.m.