conversions {hypr}

Shorthand versions for simple hypothesis translation

Description

These functions can be used to translate between null hypothesis equations, hypothesis matrices, and contrast matrices without defining a hypr object. Note that some of these functions do generate a hypr object internally but they never return one.

Usage

eqs2hmat(
  eqs,
  levels = NULL,
  order_levels = missing(levels),
  as_fractions = TRUE
)

eqs2cmat(eqs, as_fractions = TRUE)

hmat2cmat(hmat, as_fractions = TRUE)

cmat2hmat(cmat, as_fractions = TRUE)

hmat2eqs(hmat, as_fractions = TRUE)

cmat2eqs(cmat, as_fractions = TRUE)

Arguments

eqs

A list of equations

levels

(optional) A character vector of variables to be expected (if not provided, automatically generated from all terms occurring in the equations list)

order_levels

(optional) Whether to alphabetically order appearance of levels (rows in transposed hypothesis matrix or contrast matrix). Default is TRUE if levels were not explicitly provided.

as_fractions

(optional) Whether to output matrix using fractions formatting (via MASS::as.fractions). Defaults to TRUE.

hmat

Hypothesis matrix

cmat

Contrast matrix

Value

A list of equations (hmat2eqs and cmat2eqs), a contrast matrix (hmat2cmat, eqs2cmat), or a hypothesis matrix (cmat2hmat, eqs2hmat).

Functions

• eqs2hmat(): Convert null hypothesis equations to hypothesis matrix

• eqs2cmat(): Convert null hypothesis equations to contrast matrix

• hmat2cmat(): Convert hypothesis matrix to contrast matrix

• cmat2hmat(): Convert contrast matrix to hypothesis matrix

• hmat2eqs(): Convert hypothesis matrix to null hypothesis equations

• cmat2eqs(): Convert contrast matrix to null hypothesis equations

Examples

# The following examples are based on a 2-level treatment contrast (i.e., baseline and treatment).
hypotheses <- list(baseline = mu1~0, treatment = mu2~mu1)
hypothesis_matrix <- matrix(
    c(c(1, -1), c(0, 1)), ncol = 2, dimnames = list(c("baseline","treatment"), c("mu1", "mu2")))
contrast_matrix <- matrix(
    c(c(1, 1), c(0, 1)), ncol = 2, dimnames = list(c("mu1","mu2"), c("baseline", "treatment")))

# Convert a list of null hypothesis equations to ...
# ... a hypothesis matrix:
eqs2hmat(hypotheses)
# ... a contrast matrix:
eqs2cmat(hypotheses)

# Convert a hypothesis matrix to...
# ... a list of null hypothesis equations:
hmat2eqs(hypothesis_matrix)
# ... a contrast matrix:
hmat2cmat(hypothesis_matrix)

# Convert a contrast matrix to...
# ... a list of null hypothesis equations:
cmat2eqs(contrast_matrix)
# ... a hypothesis matrix:
cmat2hmat(contrast_matrix)


# Are all functions returning the expected results?
stopifnot(all.equal(eqs2hmat(hypotheses, as_fractions = FALSE), hypothesis_matrix))
stopifnot(all.equal(eqs2cmat(hypotheses, as_fractions = FALSE), contrast_matrix))
stopifnot(all.equal(hmat2cmat(hypothesis_matrix, as_fractions = FALSE), contrast_matrix))
stopifnot(all.equal(cmat2hmat(contrast_matrix, as_fractions = FALSE), hypothesis_matrix))