Package 'exceedProb'

Title: Confidence Intervals for Exceedance Probability
Description: Computes confidence intervals for the exceedance probability of normally distributed estimators. Currently only supports general linear models. Please see Segal (2019) <arXiv:1803.03356> for more information.
Authors: Brian D. Segal [aut, cre]
Maintainer: Brian D. Segal <[email protected]>
License: GPL (>= 3)
Version: 0.0.1
Built: 2025-02-12 16:46:09 UTC
Source: https://github.com/cranhaven/cranhaven.r-universe.dev

Help Index


Confidence intervals for the exceedance probability

Description

This function obtains confidence intervals for exceedance probability

Usage

exceedProb(cutoff, theta_hat, sd_hat, alpha, d, n, m, interval = c(-100,
  100), lower_tail = FALSE)

Arguments

cutoff

Cutoff values (scalar or vector)

theta_hat

Point estimate for the parameter of interest

sd_hat

Estimated standard deviation for the parameter of interest (Note: not the standard error)

alpha

Significance level

d

Number of parameters in the general linear model

n

Number of observations in the initial study

m

Number of observations in the replication study

interval

Interval within which to search for roots

lower_tail

If TRUE, reports lower tail probabilities

Value

ep Exceedance probability with confidence intervals

Examples

library(exceedProb)

# Sample mean -------------------------------------------------------
n <- 100
x <- rnorm(n = n)

theta_hat <- mean(x)
sd_hat <- sd(x)

cutoff <- seq(from = theta_hat - 0.5, to = theta_hat + 0.5, by = 0.1)

exceedProb(cutoff = cutoff, 
           theta_hat = theta_hat, 
           sd_hat = sd_hat, 
           alpha = 0.05, 
           d = 1,
           n = n,
           m = n)

# Linear regression -------------------------------------------------
n <- 100
beta <- c(1, 2)
x <-runif(n = n, min = 0, max = 10)
y <- rnorm(n = n, mean = cbind(1, x) %*% beta, sd = 1)

j <- 2
fit <- lm(y ~ x)
theta_hat <- coef(fit)[j]
sd_hat <- sqrt(n * vcov(fit)[j, j])

cutoff <- seq(from = theta_hat - 0.5, to = theta_hat + 0.5, by = 0.1)

exceedProb(cutoff = cutoff, 
           theta_hat = theta_hat, 
           sd_hat = sd_hat, 
           alpha = 0.05, 
           d = length(beta),
           n = n,
           m = n)

Confidence intervals for noncentrality parameter of t-distribution

Description

This function obtains confidence intervals for the non-centrality parameter of a t-distribution.

Usage

getDeltaCI(test_stat, alpha, d, n, interval)

Arguments

test_stat

Test statistics

alpha

Significance level

d

Number of parameters in general linear model

n

Number of observations in initial study

interval

Interval within which to search for roots

Value

ep Exceedance probability with confidence intervals (vector if cutoff is scalar and matrix otherwise)


t-distribution with Boost

Description

This function returns the cdf of a noncentral t-distribution. It is more accurate than stats::pt() for large ncp

Usage

pnct(x, df, ncp)

Arguments

x

Test statistic

df

Degrees of freedom

ncp

Noncentrality parameter

Value

Cumulative probability


This function is used to find the root for a t-distribution pivotal quantity

Description

This function returns the difference between the lower tail probability of a non-central t-distribution and a confidence level q where the t-distribution has df degrees of freedom and non-centrality parameter delta.

Usage

tRoot(delta, test_stat, df, conf_level)

Arguments

delta

Non-centrality parameter

test_stat

Test statistic at which to evaluate the t-distribution

df

Degrees of freedom

conf_level

Confidence level (usually alpha/2 or 1-alpha/2)

Value

dif Difference between t-distribution quantile and confidence level