Package 'tidydelta'

Title: Estimation of Standard Errors using Delta Method
Description: Delta Method implementation to estimate standard errors with known asymptotic properties within the 'tidyverse' workflow. The Delta Method is a statistical tool that approximates an estimator’s behaviour using a Taylor Expansion. For a comprehensive explanation, please refer to Chapter 3 of van der Vaart (1998, ISBN: 9780511802256).
Authors: Javier Martinez-Rodriguez [aut, cre, cph]
Maintainer: Javier Martinez-Rodriguez <[email protected]>
License: MIT + file LICENSE
Version: 0.1.0
Built: 2025-02-14 05:13:03 UTC
Source: https://github.com/javiermtzrdz/tidydelta

Help Index


Extract variables and their names from the formula

Description

Extract variables and their names from the formula

Usage

cases_ext(formula, mean_dta = NULL, cov_dta = NULL)

Arguments

formula

A formula object specifying the variables of interest.

mean_dta

Vector containing the means of the variables.

cov_dta

Covariance matrix of the variables.

Value

list containing objects with variables and formula


Extract variables from a formula

Description

Extracts variables from a formula string.

Usage

ext_bd_var(formula)

Arguments

formula

A formula object or a character string representing a formula.

Value

A named character vector of extracted variables.


Convert a formula to an expression

Description

Converts a formula to an expression for further evaluation.

Usage

for_to_exp(formula)

Arguments

formula

A formula object or a character string representing a formula.

Value

The evaluated expression.


Delta Method implementation

Description

Estimates standard errors for transformations of random variables using Delta method.

Usage

tidydelta(
  formula,
  normality_eval = TRUE,
  formula_vars = mean,
  mean_dta = NULL,
  cov_dta = NULL,
  n = NULL,
  conf_lev = 0.95
)

Arguments

formula

A formula object specifying the variables of interest.

normality_eval

Logical value to run normality test in case of being possible.

formula_vars

The function(s) to apply to the variables in the formula.

mean_dta

Vector containing the means of the variables.

cov_dta

Covariance matrix of the variables.

n

Sample size evaluation (in case that we can evaluate the confidence intervals with different hypnotic sample sizes).

conf_lev

Confidence level for confidence intervals.

Value

A tibble with columns for means, standard errors, and optionally, confidence intervals.

Examples

# Equivalent ways to use tidydelta()
library(tidyverse)

x <- rnorm(1000, mean = 5, sd = 2)
y <- rnorm(1000, mean = 15, sd = 3)

bd <- tibble(x, y)

tidydelta(~ y / x,
  conf_lev = .95
)

tidydelta(~ bd$y / bd$x,
  conf_lev = .95
)
bd %>%
  summarise(tidydelta(~ y / x,
    conf_lev = .95
  ))

Recursive search of environment

Description

Recursive search of environment containing object.

Usage

where_env(name, env = rlang::caller_env())

Arguments

name

Object searched

env

Initial environment to search

Value

A named character vector of extracted variables.