Fixes #482

NAMESPACE

@@ -144,6 +144,9 @@ export(util_uniform_stats_tbl)
 export(util_weibull_aic)
 export(util_weibull_param_estimate)
 export(util_weibull_stats_tbl)
+export(util_zero_truncated_geometric_aic)
+export(util_zero_truncated_geometric_param_estimate)
+export(util_zero_truncated_geometric_stats_tbl)
 export(util_zero_truncated_negative_binomial_aic)
 export(util_zero_truncated_negative_binomial_param_estimate)
 export(util_zero_truncated_negative_binomial_stats_tbl)

NEWS.md

@@ -14,6 +14,9 @@ the parameters of the zero-truncated Poisson distribution.
 Add function `util_zero_truncated_poisson_aic()` to calculate the AIC for the zero-truncated Poisson distribution. 
 Add function `util_zero_truncated_poisson_stats_tbl()` to create a summary table of the zero-truncated Poisson distribution.
 4. #472 - Add function `util_f_param_estimate()` and `util_f_aic()` to estimate the parameters and calculate the AIC for the F distribution.
+5. #482 - Add function `util_zero_truncated_geometric_param_estimate()` to estimate the parameters of the zero-truncated geometric distribution.
+Add function `util_zero_truncated_geometric_aic()` to calculate the AIC for the zero-truncated geometric distribution.
+Add function `util_zero_truncated_geometric_stats_tbl()` to create a summary table of the zero-truncated geometric distribution.
 
 ## Minor Improvements and Fixes
 1. Fix #468 - Update `util_negative_binomial_param_estimate()` to add the use of

R/est-param-zt-geometric.R

@@ -0,0 +1,121 @@
+#' Estimate Zero-Truncated Geometric Parameters
+#'
+#' @family Parameter Estimation
+#' @family Zero-Truncated Geometric
+#'
+#' @details This function will attempt to estimate the `prob` parameter of the
+#' Zero-Truncated Geometric distribution using given vector `.x` as input data.
+#' If the parameter `.auto_gen_empirical` is set to `TRUE`, the empirical data
+#' in `.x` will be run through the `tidy_empirical()` function and combined with
+#' the estimated zero-truncated geometric data.
+#'
+#' @description This function will estimate the `prob` parameter for a
+#' Zero-Truncated Geometric distribution from a given vector `.x`. The function
+#' returns a list with a parameter table, and if `.auto_gen_empirical` is set
+#' to `TRUE`, the empirical data is combined with the estimated distribution
+#' data.
+#'
+#' @param .x The vector of data to be passed to the function. Must contain
+#' non-negative integers and should have no zeros.
+#' @param .auto_gen_empirical Boolean value (default `TRUE`) that, when set to
+#' `TRUE`, will generate `tidy_empirical()` output for `.x` and combine it with
+#' the estimated distribution data.
+#'
+#' @examples
+#' library(actuar)
+#' library(dplyr)
+#' library(ggplot2)
+#' library(actuar)
+#'
+#' set.seed(123)
+#' ztg <- rztgeom(100, prob = 0.2)
+#' output <- util_zero_truncated_geometric_param_estimate(ztg)
+#'
+#' output$parameter_tbl
+#'
+#' output$combined_data_tbl |>
+#'   tidy_combined_autoplot()
+#'
+#' @return
+#' A tibble/list
+#'
+#' @name util_zero_truncated_geometric_param_estimate
+NULL
+
+#' @export
+#' @rdname util_zero_truncated_geometric_param_estimate
+
+util_zero_truncated_geometric_param_estimate <- function(.x, .auto_gen_empirical = TRUE) {
+
+  # Tidyeval ----
+  x_term <- as.numeric(.x)
+  n <- length(x_term)
+  minx <- min(as.numeric(x_term))
+  maxx <- max(as.numeric(x_term))
+  m <- mean(as.numeric(x_term))
+  s <- var(x_term)
+  sum_x <- sum(x_term)
+
+  # Checks ----
+  if (!is.vector(x_term, mode = "numeric")) {
+    rlang::abort(
+      message = "The '.x' term must be a numeric vector.",
+      use_cli_format = TRUE
+    )
+  }
+
+  if (!all(x_term == trunc(x_term)) || any(x_term <= 0)) {
+    rlang::abort(
+      message = "All values of 'x' must be positive non-zero integers.",
+      use_cli_format = TRUE
+    )
+  }
+
+  if (n < 2) {
+    rlang::abort(
+      message = "You must supply at least two data points for this function.",
+      use_cli_format = TRUE
+    )
+  }
+
+  # Estimate the prob parameter for the Zero-Truncated Geometric distribution
+  es_ztgeom_prob <- 1 / (1 + m - 1)
+
+  # Return Tibble ----
+  if (.auto_gen_empirical) {
+    te <- tidy_empirical(.x = x_term)
+    td <- tidy_zero_truncated_geometric(.n = n, .prob = round(es_ztgeom_prob, 3))
+    combined_tbl <- tidy_combine_distributions(te, td)
+  }
+
+  ret <- dplyr::tibble(
+    dist_type = "Zero-Truncated Geometric",
+    samp_size = n,
+    min = minx,
+    max = maxx,
+    mean = m,
+    variance = s,
+    sum_x = sum_x,
+    method = "Moment Estimate",
+    prob = es_ztgeom_prob
+  )
+
+  # Return ----
+  attr(ret, "tibble_type") <- "parameter_estimation"
+  attr(ret, "family") <- "zero_truncated_geometric"
+  attr(ret, "x_term") <- .x
+  attr(ret, "n") <- n
+
+  if (.auto_gen_empirical) {
+    output <- list(
+      combined_data_tbl = combined_tbl,
+      parameter_tbl     = ret
+    )
+  } else {
+    output <- list(
+      parameter_tbl = ret
+    )
+  }
+
+  return(output)
+}

R/stats-zt-geometric-tbl.R

@@ -0,0 +1,86 @@
+#' Distribution Statistics for Zero-Truncated Geometric
+#'
+#' @family Zero-Truncated Geometric
+#' @family Distribution Statistics
+#'
+#' @details This function takes in a tibble generated by a `tidy_ztgeom`
+#' distribution function and returns the relevant statistics for a Zero-Truncated
+#' Geometric distribution. It requires data to be passed from a `tidy_ztgeom`
+#' distribution function.
+#'
+#' @description Returns distribution statistics for Zero-Truncated Geometric
+#' distribution in a tibble.
+#'
+#' @param .data The data being passed from a `tidy_ztgeom` distribution function.
+#'
+#' @examples
+#' library(dplyr)
+#'
+#' set.seed(123)
+#' tidy_zero_truncated_geometric(.prob = 0.1) |>
+#'   util_zero_truncated_geometric_stats_tbl() |>
+#'   glimpse()
+#'
+#' @return
+#' A tibble
+#'
+#' @name util_zero_truncated_geometric_stats_tbl
+NULL
+
+#' @export
+#' @rdname util_zero_truncated_geometric_stats_tbl
+
+util_zero_truncated_geometric_stats_tbl <- function(.data) {
+
+  # Immediate check for tidy_ distribution function
+  if (!"tibble_type" %in% names(attributes(.data))) {
+    rlang::abort(
+      message = "You must pass data from a 'tidy_dist' function.",
+      use_cli_format = TRUE
+    )
+  }
+
+  if (attributes(.data)$tibble_type != "tidy_zero_truncated_geometric") {
+    rlang::abort(
+      message = "You must use 'tidy_zero_truncated_geometric()'",
+      use_cli_format = TRUE
+    )
+  }
+
+  # Extract attributes
+  data_tbl <- dplyr::as_tibble(.data)
+  atb <- attributes(data_tbl)
+  p <- atb$.prob
+
+  # Zero-Truncated Geometric Statistics Calculation
+  stat_mean <- (1 - p) / p + 1
+  stat_mode <- 1
+  stat_sd <- sqrt((1 - p) / (p * p))
+  stat_skewness <- (2 + p) / sqrt(1 - p)
+  stat_kurtosis <- 6 + (p * (p - 2)) / (1 - p)
+  stat_coef_var <- stat_sd / stat_mean
+
+  # Generate data table with calculated statistics
+  ret <- dplyr::tibble(
+    tidy_function = atb$tibble_type,
+    function_call = atb$dist_with_params,
+    distribution = dist_type_extractor(atb$tibble_type),
+    distribution_type = atb$distribution_family_type,
+    points = atb$.n,
+    simulations = atb$.num_sims,
+    mean = stat_mean,
+    mode = stat_mode,
+    range = "1 to Inf",
+    std_dv = stat_sd,
+    coeff_var = stat_coef_var,
+    skewness = stat_skewness,
+    kurtosis = stat_kurtosis,
+    computed_std_skew = tidy_skewness_vec(data_tbl$y),
+    computed_std_kurt = tidy_kurtosis_vec(data_tbl$y),
+    ci_lo = ci_lo(data_tbl$y),
+    ci_hi = ci_hi(data_tbl$y)
+  )
+
+  # Return the data table
+  return(ret)
+}

R/utils-aic-zt-geometric.R

@@ -0,0 +1,75 @@
+#' Calculate Akaike Information Criterion (AIC) for Zero-Truncated Geometric Distribution
+#'
+#' This function calculates the Akaike Information Criterion (AIC) for a
+#' Zero-Truncated Geometric distribution fitted to the provided data.
+#'
+#' @family Utility
+#' @author Steven P. Sanderson II, MPH
+#'
+#' @description
+#' This function estimates the probability parameter of a Zero-Truncated Geometric
+#' distribution from the provided data and calculates the AIC value based on the
+#' fitted distribution.
+#'
+#' @param .x A numeric vector containing the data to be fitted to a Zero-Truncated
+#' Geometric distribution.
+#'
+#' @details
+#' This function fits a Zero-Truncated Geometric distribution to the provided
+#' data. It estimates the probability parameter using the method of moments and
+#' calculates the AIC value.
+#'
+#' Optimization method: Since the parameter is directly calculated from the data,
+#' no optimization is needed.
+#'
+#' Goodness-of-fit: While AIC is a useful metric for model comparison, it's
+#' recommended to also assess the goodness-of-fit of the chosen model using
+#' visualization and other statistical tests.
+#'
+#' @examples
+#' library(actuar)
+#'
+#' # Example: Calculate AIC for a sample dataset
+#' set.seed(123)
+#' x <- rztgeom(100, prob = 0.2)
+#' util_zero_truncated_geometric_aic(x)
+#'
+#' @return
+#' The AIC value calculated based on the fitted Zero-Truncated Geometric
+#' distribution to the provided data.
+#'
+#' @name util_zero_truncated_geometric_aic
+NULL
+
+#' @export
+#' @rdname util_zero_truncated_geometric_aic
+util_zero_truncated_geometric_aic <- function(.x) {
+  # Tidyeval
+  x <- as.numeric(.x)
+
+  # Check input validity
+  if (any(x <= 0)) {
+    rlang::abort(
+      message = "All values of '.x' must be positive non-zero integers.",
+      use_cli_format = TRUE
+    )
+  }
+
+  # Estimate the probability parameter for Zero-Truncated Geometric distribution
+  prob <- TidyDensity::util_zero_truncated_geometric_param_estimate(x)$parameter_tbl |>
+    dplyr::pull(prob)
+
+  # Calculate log-likelihood for Zero-Truncated Geometric distribution
+  k_ztgeom <- 1  # Number of parameters for the Zero-Truncated Geometric distribution (prob)
+  logLik_ztgeom <- sum(actuar::dztgeom(x, prob = prob, log = TRUE))
+
+  # Adjust for zero truncation (exclusion of zero)
+  logLik_adjustment <- -length(x) * log(1 - actuar::dztgeom(0, prob = prob))
+  logLik_ztgeom <- logLik_ztgeom + logLik_adjustment
+
+  # Calculate AIC
+  AIC_ztgeom <- 2 * k_ztgeom - 2 * logLik_ztgeom
+
+  # Return AIC
+  return(AIC_ztgeom)
+}

docs/pkgdown.yml

@@ -3,7 +3,7 @@ pkgdown: 2.0.9
 pkgdown_sha: ~
 articles:
   getting-started: getting-started.html
-last_built: 2024-05-09T15:29Z
+last_built: 2024-05-10T19:05Z
 urls:
   reference: https://www.spsanderson.com/TidyDensity/reference
   article: https://www.spsanderson.com/TidyDensity/articles