factor_to_logical: Convert factors to logicals
In emil: Evaluation of Modeling without Information Leakage

Description Usage Arguments Author(s) Examples

Factors are converted to logical vectors or matrices depending on the number of levels. Ordered factors are converted to matrices where each column represent a level, coded TRUE for observations that match the level and FALSE otherwise. Unordered factors are converted in a similar way but coded TRUE for observations that match the level or a higher level. Interpred in words, the star rating example below returns a matrix containing a column named “3 stars” that contains TRUE for observations with at least three stars and FALSE for observations with fewer than three stars.

1	factor_to_logical(x, base = 1L, drop = TRUE)

`x`	Factor.
`base`	Level to consider as the basis for comparison. Can be either integer or character. Note that `base = 4` is interpreted as a level named "4", but `base = 4L` is interpreted as the fourth level.
`drop`	Whether to keep the base level. The base level column never holds any information that cannot be deduced from the remaining columns.

Christofer Bäcklin

# Binary factor
email <- factor(sample(2, 20, TRUE), labels=c("unverified", "verified"))
factor_to_logical(email)

# Unordered multi-level factors
wine_preferences <- factor(sample(3, 20, TRUE), 
                           labels=c("red", "white", "none"))
factor_to_logical(wine_preferences, base="none")

fruit <- factor(sample(4, 20, TRUE),
                labels = c("apple", "banana", "cantaloup", "durian"))
fruit[sample(length(fruit), 3)] <- NA
factor_to_logical(fruit, drop=FALSE)

# Ordered factor
rating <- factor(1:5, labels = paste(1:5, "stars"), ordered=TRUE)
factor_to_logical(rating)

# Ordered factor with custom base
tie_break <- factor(1:5, 
                    labels=c("SetAlice", "AdvAlice", "Deuce", "AdvBob", "SetBob"),
                    ordered = TRUE)
tie_status <- as.data.frame(
    factor_to_logical(tie_break, base="Deuce", drop=FALSE)
)
print(tie_status)
tie_break[tie_status$AdvAlice]
tie_break[tie_status$SetBob]
tie_break[tie_status$Deuce]