shift_dist: Shift the scale of a habitual intake distribution

In cfree14/nutriR: Nutritional intake functions for R

Shift the scale of a habitual intake distribution

Description

This function shifts the scale of a habitual intake distribution and provides the new parameters used to describe the shifted distribution. The shift in scale is defined by either a shift in the mean or median of of the habitual intake distribution.

Usage

shift_dist(
  shape = NULL,
  rate = NULL,
  meanlog = NULL,
  sdlog = NULL,
  by = NULL,
  to = NULL,
  type = "mean",
  plot = F
)

Arguments

shape	Shape parameter for gamma distribution
rate	Rate parameter for gamma distribution
meanlog	Mean parameter for gamma distribution
sdlog	Standard deviation parameter for gamma distribution
by	Amount to shift the current mean/median by
to	New mean/median to shift the current mean/median to
type	Measure of scale to shift ("mean" or "median"); mean is default
plot	Boolean (TRUE/FALSE) indicating whether to plot the current/shifted distributions

Value

A list with the parameters for the shifted distribution

Examples

# Shift gamma distribution by an amount (2 and -3)
shift_dist(shape=9.7, rate=1.25, by=2, plot=T)
shift_dist(shape=9.7, rate=1.25, by=-3, plot=T)

# Shift gamma distribution to a new mean (10 or 4)
shift_dist(shape=9.7, rate=1.25, to=10, plot=T)
shift_dist(shape=9.7, rate=1.25, to=4, plot=T)

# Shift log-normal distribution by an amount (10 and -5)
shift_dist(meanlog=3, sdlog=0.5, by=10, plot=T)
shift_dist(meanlog=3, sdlog=0.5, by=-5, plot=T)

# Shift log-normal distribution to a new mean (35 and 15)
shift_dist(meanlog=3, sdlog=0.5, to=35, plot=T)
shift_dist(meanlog=3, sdlog=0.5, to=15, plot=T)

cfree14/nutriR documentation built on Oct. 31, 2024, 6:27 p.m.