igrade: Calculate distribution of grades

In mrhelmus/ieco: Functions used to perform integratice ecology research

Description

Calculate the grades of a class of students, given raw scores on exam

Usage

do.grades.ieco(grades, divs = NULL, cut = 0, tit = "Exam Grades",
  breaks = length(grades)/3, labels = c("F", "D", "C", "B", "A"), ...)

getlet.ieco(grades, divs, full.divs = c(0, 60, 63, 67, 70, 73, 77, 80, 83, 87,
  90, 93, 97), full.labels = c("F", "D-", "D", "D+", "C-", "C", "C+", "B-",
  "B", "B+", "A-", "A", "A+"), noAplus = TRUE)

Arguments

grades	Raw grades
divs	divisions for grades (optional)
cut	low end Cut off to remove 0 from statistics
tit	Title for Figure
breaks	breaks for the histogram, default=length(grades)/3
labels	grade labels, default are the U.S.A. system of five letter grades, ABCDF
...	other parameters for hist
full.divs	divisions for all grades not just main grades as in div
full.labels	names of all the grades
noAplus	remove the first (A+) listed grade and assign the second (A)

Details

To remove students who do not take the test a low end cut off is used to excise any grades below that level. Both mean, and standard deviations are shown as well as median and quartiles.

Value

the data set

Author(s)

Jonathan M. Lees from the ProfessR package, with edits by M.R. Helmus

Examples

g = rnorm(n=130, m=82, sd=10)
g[g>100] = 100
g[g<1] = 1

B = boxplot(g)
##########   set divisions automatically:
divs = c(min(g), B$stats[1:4] + diff(B$stats)/2, max(g) )
D1 = do.grades.ieco(g, divs=divs, tit="GEOL 105 Exam 1")

mrhelmus/ieco documentation built on May 23, 2019, 7:37 a.m.