ttest_data {exams.forge}

T-tests and Data Creation

Description

Creates data for a t-test, for one mean, based on the test's properties.

Usage

ttest_data(
  size = (3:20)^2,
  mean = -5:5,
  sd = seq(0.1, 1, by = 0.1),
  reject = NA,
  alternative = c("two.sided", "less", "greater"),
  alpha = c(0.01, 0.05, 0.1),
  z = seq(-4.49, 4.49, by = 0.01),
  use.sigma = TRUE
)

dt1(
  size = (3:20)^2,
  mean = -5:5,
  sd = seq(0.1, 1, by = 0.1),
  reject = NA,
  alternative = c("two.sided", "less", "greater"),
  alpha = c(0.01, 0.05, 0.1),
  z = seq(-4.49, 4.49, by = 0.01),
  use.sigma = TRUE
)

Arguments

size

numeric: vector of possible sample sizes (default (3:20)^2,)

mean

numeric: vector of possible means (default -5:5)

sd

numeric: vector of possible standard deviations (default sd=seq(0.1, 1, by=0.1)

reject

logical: should x generate a lead for the rejection of the null hypothesis (default TRUE), if equals NA then this will be ignored

alternative

character: a character string specifying the alternative hypothesis, must be one of two.sided (default), greater or less

alpha

numeric: vector of significance levels (default c(0.01, 0.05, 0.1))

z

numeric: vector of possible z values (default seq(-4.49, 4.49, by=0.01))

use.sigma

logical: should the standard deviation of the population (default) or the sample be used?

Value

A list with the components:

• mu0 hypothetical mean

• sigma standard deviation in the population

• sd vector of possible standard deviations in the sample

• xbar mean in the sample

• n sample size

• alpha significance level

• alternative specifying the alternative hypothesis (either two.sided, greater or less)

• altsd alternative values usable for sd (if use.sigma==TRUE) or sigma (if use.sigma==FALSE)

Examples

ttest_data()