R/utilities.R

Defines functions upper.ci lower.ci sem co2_convertion co2_convertion_median

Documented in co2_convertion co2_convertion_median lower.ci sem upper.ci

#' Calculate median CO2(ul/h)
#'
#' @param x list of CO2 values from MAVEn dataset
#'
#' @return Converted median CO2 measurement
#' 
#' @importFrom stats median
#'
co2_convertion_median <- function(x) {
    co2.ul.h <- median(x) * 1000 * 60
    return(co2.ul.h)
}

#' Convert CO2 MAVEn measurement to CO2 (ul/h)
#'
#' @param x list of CO2 values from MAVEn dataset
#'
#' @return list of converted CO2 measurement from ml/min to ul/hr.
#'
co2_convertion <- function(x) {
    co2.ul.h <- x * 1000 * 60
    return(co2.ul.h)
}

#' Standard error of the mean
#'
#' @param x list of values
#' @param n number of cycles
#'
#' @return Standard Error of Meatn
#' 
#' @importFrom stats sd
#'
sem <- function(x, n) {
    sem <- sd(x)/sqrt(n)
    return(sem)
}


#' Lower confidence interval
#'
#' @param x list of values
#' @param n number of cycles
#'
#' @return list of lower confidence intervals
#' 
#' @importFrom stats qt
#'
lower.ci <- function(x, n) {
    lower.ci <- mean(x) - qt(1 - (0.05/2), n - 1) * sem(x, n)
    return(lower.ci)
}


#' Upper confidence interval
#'
#' @param x list of values
#' @param n number of cycles
#'
#' @return list of upper confidence intervals
#' 
#' @importFrom stats qt
#'
upper.ci <- function(x, n) {
    upper.ci <- mean(x) + qt(1 - (0.05/2), n - 1) * sem(x, n)
    return(upper.ci)
}
dapperstats/MAVEn documentation built on Jan. 22, 2021, 3:39 p.m.