Has anyone written code to add a column to the psych::describe() output that identifies the statistical mode for each variable? Or, how would you go about achieving this?
For example, using the dataset mtcars, we can easily generate descriptive statistics for the data using the psych package, but the statistical mode is not included in the output.
> mydata = mtcars
> head(mydata)
mpg cyl disp hp drat wt qsec vs am gear carb
Mazda RX4 21.0 6 160 110 3.90 2.620 16.46 0 1 4 4
Mazda RX4 Wag 21.0 6 160 110 3.90 2.875 17.02 0 1 4 4
Datsun 710 22.8 4 108 93 3.85 2.320 18.61 1 1 4 1
Hornet 4 Drive 21.4 6 258 110 3.08 3.215 19.44 1 0 3 1
Hornet Sportabout 18.7 8 360 175 3.15 3.440 17.02 0 0 3 2
Valiant 18.1 6 225 105 2.76 3.460 20.22 1 0 3 1
> library(psych)
> describe(mydata)
vars n mean sd median trimmed mad min max range skew kurtosis se
mpg 1 32 20.09 6.03 19.20 19.70 5.41 10.40 33.90 23.50 0.61 -0.37 1.07
cyl 2 32 6.19 1.79 6.00 6.23 2.97 4.00 8.00 4.00 -0.17 -1.76 0.32
disp 3 32 230.72 123.94 196.30 222.52 140.48 71.10 472.00 400.90 0.38 -1.21 21.91
hp 4 32 146.69 68.56 123.00 141.19 77.10 52.00 335.00 283.00 0.73 -0.14 12.12
drat 5 32 3.60 0.53 3.70 3.58 0.70 2.76 4.93 2.17 0.27 -0.71 0.09
wt 6 32 3.22 0.98 3.33 3.15 0.77 1.51 5.42 3.91 0.42 -0.02 0.17
qsec 7 32 17.85 1.79 17.71 17.83 1.42 14.50 22.90 8.40 0.37 0.34 0.32
vs 8 32 0.44 0.50 0.00 0.42 0.00 0.00 1.00 1.00 0.24 -2.00 0.09
am 9 32 0.41 0.50 0.00 0.38 0.00 0.00 1.00 1.00 0.36 -1.92 0.09
gear 10 32 3.69 0.74 4.00 3.62 1.48 3.00 5.00 2.00 0.53 -1.07 0.13
carb 11 32 2.81 1.62 2.00 2.65 1.48 1.00 8.00 7.00 1.05 1.26 0.29
Given that the output of psych::describe(mydata) does not include information for the statistical mode for each variable in the dataset, how can we add a column to the psych::describe(mydata) output for statistical mode for each variable in the dataset?
For context, I have no problem adding and using a function for identifying statistical mode, but generating the output for it requires me to ask for it individually by variable. I've tried various ways of adding a column for statistical mode to the psych::describe (mydata) output, but invariably there are weird errors.
To generate modes I have both written the function for it
getmode <- function(v) {
uniqv <- unique(v)
uniqv[which.max(tabulate(match(v, uniqv)))]
}
and used the package DescTools, but both require me to name a variable to generate its mode. I would like to do this for every column in the mtcars data frame.
tldr; I would like to add a column after "se" in the psych::describe(mydata) output that describes the statistical mode for every variable. What do you recommend?
You may cbind the additional function to describe output to get it as a new column.
library(psych)
result <- cbind(describe(mydata), Mode = sapply(mydata, getmode))
result
# vars n mean sd median trimmed mad min max range skew kurtosis se Mode
#mpg 1 32 20.09 6.03 19.2 19.70 5.41 10.4 33.9 23.5 0.61 -0.373 1.065 21.0
#cyl 2 32 6.19 1.79 6.0 6.23 2.97 4.0 8.0 4.0 -0.17 -1.762 0.316 8.0
#disp 3 32 230.72 123.94 196.3 222.52 140.48 71.1 472.0 400.9 0.38 -1.207 21.909 275.8
#hp 4 32 146.69 68.56 123.0 141.19 77.10 52.0 335.0 283.0 0.73 -0.136 12.120 110.0
#drat 5 32 3.60 0.53 3.7 3.58 0.70 2.8 4.9 2.2 0.27 -0.715 0.095 3.9
#wt 6 32 3.22 0.98 3.3 3.15 0.77 1.5 5.4 3.9 0.42 -0.023 0.173 3.4
#qsec 7 32 17.85 1.79 17.7 17.83 1.42 14.5 22.9 8.4 0.37 0.335 0.316 17.0
#vs 8 32 0.44 0.50 0.0 0.42 0.00 0.0 1.0 1.0 0.24 -2.002 0.089 0.0
#am 9 32 0.41 0.50 0.0 0.38 0.00 0.0 1.0 1.0 0.36 -1.925 0.088 0.0
#gear 10 32 3.69 0.74 4.0 3.62 1.48 3.0 5.0 2.0 0.53 -1.070 0.130 3.0
#carb 11 32 2.81 1.62 2.0 2.65 1.48 1.0 8.0 7.0 1.05 1.257 0.286 4.0