miceFast (version 0.8.2)

fill_NA_N: fill_NA_N function for the multiple imputations purpose

Description

Multiple imputations to fill the missing data. Non missing independent variables are used to approximate a missing observations for a dependent variable. Quantitative models were built under Rcpp packages and the C++ library Armadillo.

Usage

fill_NA_N(
  x,
  model,
  posit_y,
  posit_x,
  w = NULL,
  logreg = FALSE,
  k = 10,
  ridge = 1e-06
)
# S3 method for data.frame
fill_NA_N(
  x,
  model,
  posit_y,
  posit_x,
  w = NULL,
  logreg = FALSE,
  k = 10,
  ridge = 1e-06
)
# S3 method for data.table
fill_NA_N(
  x,
  model,
  posit_y,
  posit_x,
  w = NULL,
  logreg = FALSE,
  k = 10,
  ridge = 1e-06
)
# S3 method for matrix
fill_NA_N(
  x,
  model,
  posit_y,
  posit_x,
  w = NULL,
  logreg = FALSE,
  k = 10,
  ridge = 1e-06
)

Value

load imputations in a numeric/character/factor (similar to the input type) vector format

Arguments

x

a numeric matrix or data.frame/data.table (factor/character/numeric/logical) - variables

model

a character - posibble options ("lm_bayes","lm_noise","pmm")

posit_y

an integer/character - a position/name of dependent variable

posit_x

an integer/character vector - positions/names of independent variables

w

a numeric vector - a weighting variable - only positive values, Default: NULL

logreg

a boolean - if dependent variable has log-normal distribution (numeric). If TRUE log-regression is evaluated and then returned exponential of results., Default: FALSE

k

an integer - a number of multiple imputations or for pmm a number of closest points from which a one random value is taken, Default:10

ridge

a numeric - a value added to diagonal elements of the x'x matrix, Default:1e-5

Methods (by class)

• fill_NA_N(data.frame): s3 method for data.frame

• fill_NA_N(data.table): S3 method for data.table

• fill_NA_N(matrix): S3 method for matrix

See Also

fill_NA VIF

Examples

library(miceFast)
library(dplyr)
library(data.table)
### Data
# airquality dataset with additional variables
data(air_miss)
### Intro: dplyr
# IMPUTATIONS
air_miss <- air_miss %>%
  # Imputations with a grouping option (models are separately assessed for each group)
  # taking into account provided weights
  group_by(groups) %>%
  do(mutate(., Solar_R_imp = fill_NA(
    x = .,
    model = "lm_pred",
    posit_y = "Solar.R",
    posit_x = c("Wind", "Temp", "Intercept"),
    w = .[["weights"]]
  ))) %>%
  ungroup() %>%
  # Imputations - discrete variable
  mutate(x_character_imp = fill_NA(
    x = .,
    model = "lda",
    posit_y = "x_character",
    posit_x = c("Wind", "Temp")
  )) %>%
  # logreg was used because almost log-normal distribution of Ozone
  # imputations around mean
  mutate(Ozone_imp1 = fill_NA(
    x = .,
    model = "lm_bayes",
    posit_y = "Ozone",
    posit_x = c("Intercept"),
    logreg = TRUE
  )) %>%
  # imputations using positions - Intercept, Temp
  mutate(Ozone_imp2 = fill_NA(
    x = .,
    model = "lm_bayes",
    posit_y = 1,
    posit_x = c(4, 6),
    logreg = TRUE
  )) %>%
  # multiple imputations (average of x30 imputations)
  # with a factor independent variable, weights and logreg options
  mutate(Ozone_imp3 = fill_NA_N(
    x = .,
    model = "lm_noise",
    posit_y = "Ozone",
    posit_x = c("Intercept", "x_character_imp", "Wind", "Temp"),
    w = .[["weights"]],
    logreg = TRUE,
    k = 30
  )) %>%
  mutate(Ozone_imp4 = fill_NA_N(
    x = .,
    model = "lm_bayes",
    posit_y = "Ozone",
    posit_x = c("Intercept", "x_character_imp", "Wind", "Temp"),
    w = .[["weights"]],
    logreg = TRUE,
    k = 30
  )) %>%
  group_by(groups) %>%
  do(mutate(., Ozone_imp5 = fill_NA(
    x = .,
    model = "lm_pred",
    posit_y = "Ozone",
    posit_x = c("Intercept", "x_character_imp", "Wind", "Temp"),
    w = .[["weights"]],
    logreg = TRUE
  ))) %>%
  do(mutate(., Ozone_imp6 = fill_NA_N(
    x = .,
    model = "pmm",
    posit_y = "Ozone",
    posit_x = c("Intercept", "x_character_imp", "Wind", "Temp"),
    w = .[["weights"]],
    logreg = TRUE,
    k = 20
  ))) %>%
  ungroup() %>%
  # Average of a few methods
  mutate(Ozone_imp_mix = rowMeans(select(., starts_with("Ozone_imp")))) %>%
  # Protecting against collinearity or low number of observations - across small groups
  # Be carful when using a grouping option
  # because of lack of protection against collinearity or low number of observations.
  # There could be used a tryCatch(fill_NA(...),error=function(e) return(...))
  group_by(groups) %>%
  do(mutate(., Ozone_chac_imp = tryCatch(
    fill_NA(
      x = .,
      model = "lda",
      posit_y = "Ozone_chac",
      posit_x = c(
        "Intercept",
        "Month",
        "Day",
        "Temp",
        "x_character_imp"
      ),
      w = .[["weights"]]
    ),
    error = function(e) .[["Ozone_chac"]]
  ))) %>%
  ungroup()

# Sample of results
air_miss[which(is.na(air_miss[, 1]))[1:5], ]

### Intro: data.table
# IMPUTATIONS
# Imputations with a grouping option (models are separately assessed for each group)
# taking into account provided weights
data(air_miss)
setDT(air_miss)
air_miss[, Solar_R_imp := fill_NA_N(
  x = .SD,
  model = "lm_bayes",
  posit_y = "Solar.R",
  posit_x = c("Wind", "Temp", "Intercept"),
  w = .SD[["weights"]],
  k = 100
), by = .(groups)] %>%
  # Imputations - discrete variable
  .[, x_character_imp := fill_NA(
    x = .SD,
    model = "lda",
    posit_y = "x_character",
    posit_x = c("Wind", "Temp", "groups")
  )] %>%
  # logreg was used because almost log-normal distribution of Ozone
  # imputations around mean
  .[, Ozone_imp1 := fill_NA(
    x = .SD,
    model = "lm_bayes",
    posit_y = "Ozone",
    posit_x = c("Intercept"),
    logreg = TRUE
  )] %>%
  # imputations using positions - Intercept, Temp
  .[, Ozone_imp2 := fill_NA(
    x = .SD,
    model = "lm_bayes",
    posit_y = 1,
    posit_x = c(4, 6),
    logreg = TRUE
  )] %>%
  # model with a factor independent variable
  # multiple imputations (average of x30 imputations)
  # with a factor independent variable, weights and logreg options
  .[, Ozone_imp3 := fill_NA_N(
    x = .SD,
    model = "lm_noise",
    posit_y = "Ozone",
    posit_x = c("Intercept", "x_character_imp", "Wind", "Temp"),
    w = .SD[["weights"]],
    logreg = TRUE,
    k = 30
  )] %>%
  .[, Ozone_imp4 := fill_NA_N(
    x = .SD,
    model = "lm_bayes",
    posit_y = "Ozone",
    posit_x = c("Intercept", "x_character_imp", "Wind", "Temp"),
    w = .SD[["weights"]],
    logreg = TRUE,
    k = 30
  )] %>%
  .[, Ozone_imp5 := fill_NA(
    x = .SD,
    model = "lm_pred",
    posit_y = "Ozone",
    posit_x = c("Intercept", "x_character_imp", "Wind", "Temp"),
    w = .SD[["weights"]],
    logreg = TRUE
  ), .(groups)] %>%
  .[, Ozone_imp6 := fill_NA_N(
    x = .SD,
    model = "pmm",
    posit_y = "Ozone",
    posit_x = c("Intercept", "x_character_imp", "Wind", "Temp"),
    w = .SD[["weights"]],
    logreg = TRUE,
    k = 10
  ), .(groups)] %>%
  # Average of a few methods
  .[, Ozone_imp_mix := apply(.SD, 1, mean), .SDcols = Ozone_imp1:Ozone_imp6] %>%
  # Protecting against collinearity or low number of observations - across small groups
  # Be carful when using a data.table grouping option
  # because of lack of protection against collinearity or low number of observations.
  # There could be used a tryCatch(fill_NA(...),error=function(e) return(...))

  .[, Ozone_chac_imp := tryCatch(
    fill_NA(
      x = .SD,
      model = "lda",
      posit_y = "Ozone_chac",
      posit_x = c(
        "Intercept",
        "Month",
        "Day",
        "Temp",
        "x_character_imp"
      ),
      w = .SD[["weights"]]
    ),
    error = function(e) .SD[["Ozone_chac"]]
  ), .(groups)]

# Sample of results
air_miss[which(is.na(air_miss[, 1]))[1:5], ]