| sim.my {chngpt} | R Documentation |
Simulate data
Description
Simulate data
Usage
sim.my(n, seed, label, alpha, beta, e. = NULL, b. = NULL, tr. = NULL)
Arguments
n |
Sample size |
seed |
Seed for random number generator |
label |
A character string which specifies the simulation scenario. sigmoid4, sigmoidgam4, elbow4 |
alpha |
regression parameter |
beta |
regression parameter |
e. |
inflection point for the logistic transformation (the log scale) |
b. |
slope for the logistic transformation |
tr. |
threshold point |
Details
When the label starts with elbow, the transformation on x.star is elbow shaped. When the label starts with sigmoid, the transformation on x.star is sigmoid shaped. Data simulated from logit(Pr(Y==1))=alpha + beta*(transformed x.star).
Value
A data frame with columns: y, x.star, x.star.expit (if label starts with sigmoid), x.star.tr (if label starts with elbow), x.bin.med (x.star dichotomized at median), x.tri (x.star trichotomized at tertiles).
Examples
alpha=-1; beta=log(0.2)
e.=5; b.=-30; t.=1
dat=sim.my(n=250, seed=1, label="sigmoid4", alpha, beta, e.=e., b.=b.)