Sample mode

Calculate the most frequently occurring value(s) in a sample (modeOf) or the frequency of the most common value (maxFreq).

Usage

modeOf(x, na.rm = TRUE)

maxFreq(x, na.rm = TRUE)

Arguments

x

A vector or factor containing the observations.

na.rm

Set to TRUE (the default) to remove missing values before computing the mode. Set to FALSE to treat NA as a possible modal value (see Details).

Value

modeOf returns the most frequently observed value. If multiple values are tied for the highest frequency, all of them are returned as a vector. If the input has no non-missing values, modeOf issues a warning and returns NA. maxFreq returns the modal frequency as a single number, or NA with a warning if the input has no non-missing values.

Details

When na.rm = FALSE, missing values are treated as a distinct value that can itself be the mode. If the number of NAs exceeds the frequency of every other value, modeOf returns NA and maxFreq returns the count of missing values.

Because of this ambiguity, the default is na.rm = TRUE, unlike most other functions in this package.

See also

mean, median, table

Examples

eyes <- c("green", "green", "brown", "brown", "blue")
modeOf(eyes) # returns c("green", "brown") -- a tie
#> [1] "green" "brown"
maxFreq(eyes) # returns 2
#> [1] 2

# with missing data
eyes <- c("green", "green", "brown", "brown", "blue", NA, NA, NA)

# na.rm = FALSE: NA is the most frequent "value"
modeOf(eyes, na.rm = FALSE)
#> [1] NA
maxFreq(eyes, na.rm = FALSE)
#> [1] 3

# na.rm = TRUE: missing values ignored
modeOf(eyes, na.rm = TRUE)
#> [1] "green" "brown"
maxFreq(eyes, na.rm = TRUE)
#> [1] 2
NULL
#> NULL