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authorNaeem Model <me@nmode.ca>2023-06-23 01:38:27 +0000
committerNaeem Model <me@nmode.ca>2023-06-23 01:38:27 +0000
commit5802a8d248c4f02187b4fcd6a405cfa1ed916b81 (patch)
tree5d120a981c1c5a88db79dc3dfde4c7cef867dca2 /R
parent5f4889d4df5e94f194ef7f8b839496db04b17f4e (diff)
Normalize line endings
Diffstat (limited to 'R')
-rw-r--r--R/ID.R96
-rw-r--r--R/IDEA.R116
2 files changed, 106 insertions, 106 deletions
diff --git a/R/ID.R b/R/ID.R
index cd991a4..0e3cc35 100644
--- a/R/ID.R
+++ b/R/ID.R
@@ -1,48 +1,48 @@
-#' ID method
-#'
-#' This function implements a least squares estimation method of R0 due to Fisman et al. (PloS One, 2013).
-#' See details for implementation notes.
-#'
-#' The method is based on a straightforward incidence decay model. The estimate of R0 is the value which
-#' minimizes the sum of squares between observed case counts and cases counts 'expected' under the model.
-#'
-#' This method is based on an approximation of the SIR model, which is most valid at the beginning of an epidemic.
-#' The method assumes that the mean of the serial distribution (sometimes called the serial interval) is known.
-#' The final estimate can be quite sensitive to this value, so sensitivity testing is strongly recommended.
-#' Users should be careful about units of time (e.g., are counts observed daily or weekly?) when implementing.
-#'
-#' @param NT Vector of case counts.
-#' @param mu Mean of the serial distribution. This needs to match case counts in time units. For example, if case counts
-#' are weekly and the serial distribution has a mean of seven days, then \code{mu} should be set to one If case
-#' counts are daily and the serial distribution has a mean of seven days, then \code{mu} should be set to seven.
-#'
-#' @return \code{ID} returns a single value, the estimate of R0.
-#'
-#' @examples
-#' ## ===================================================== ##
-#' ## Illustrate on weekly data ##
-#' ## ===================================================== ##
-#'
-#' NT <- c(1, 4, 10, 5, 3, 4, 19, 3, 3, 14, 4)
-#' ## obtain Rhat when serial distribution has mean of five days
-#' ID(NT=NT, mu=5/7)
-#' ## obtain Rhat when serial distribution has mean of three days
-#' ID(NT=NT, mu=3/7)
-#'
-#' ## ========================================================= ##
-#' ## Compute Rhat using only the first five weeks of data ##
-#' ## ========================================================= ##
-#'
-#' ID(NT=NT[1:5], mu=5/7) # serial distribution has mean of five days
-#'
-#' @export
-ID <- function(NT, mu) {
- NT <- as.numeric(NT)
- TT <- length(NT)
- s <- (1:TT) / mu
- y <- log(NT) / s
-
- R0_ID <- exp(sum(y) / TT)
-
- return(R0_ID)
-}
+#' ID method
+#'
+#' This function implements a least squares estimation method of R0 due to Fisman et al. (PloS One, 2013).
+#' See details for implementation notes.
+#'
+#' The method is based on a straightforward incidence decay model. The estimate of R0 is the value which
+#' minimizes the sum of squares between observed case counts and cases counts 'expected' under the model.
+#'
+#' This method is based on an approximation of the SIR model, which is most valid at the beginning of an epidemic.
+#' The method assumes that the mean of the serial distribution (sometimes called the serial interval) is known.
+#' The final estimate can be quite sensitive to this value, so sensitivity testing is strongly recommended.
+#' Users should be careful about units of time (e.g., are counts observed daily or weekly?) when implementing.
+#'
+#' @param NT Vector of case counts.
+#' @param mu Mean of the serial distribution. This needs to match case counts in time units. For example, if case counts
+#' are weekly and the serial distribution has a mean of seven days, then \code{mu} should be set to one If case
+#' counts are daily and the serial distribution has a mean of seven days, then \code{mu} should be set to seven.
+#'
+#' @return \code{ID} returns a single value, the estimate of R0.
+#'
+#' @examples
+#' ## ===================================================== ##
+#' ## Illustrate on weekly data ##
+#' ## ===================================================== ##
+#'
+#' NT <- c(1, 4, 10, 5, 3, 4, 19, 3, 3, 14, 4)
+#' ## obtain Rhat when serial distribution has mean of five days
+#' ID(NT=NT, mu=5/7)
+#' ## obtain Rhat when serial distribution has mean of three days
+#' ID(NT=NT, mu=3/7)
+#'
+#' ## ========================================================= ##
+#' ## Compute Rhat using only the first five weeks of data ##
+#' ## ========================================================= ##
+#'
+#' ID(NT=NT[1:5], mu=5/7) # serial distribution has mean of five days
+#'
+#' @export
+ID <- function(NT, mu) {
+ NT <- as.numeric(NT)
+ TT <- length(NT)
+ s <- (1:TT) / mu
+ y <- log(NT) / s
+
+ R0_ID <- exp(sum(y) / TT)
+
+ return(R0_ID)
+}
diff --git a/R/IDEA.R b/R/IDEA.R
index 20a9401..854acd7 100644
--- a/R/IDEA.R
+++ b/R/IDEA.R
@@ -1,58 +1,58 @@
-#' IDEA method
-#'
-#' This function implements a least squares estimation method of R0 due to Fisman et al. (PloS One, 2013).
-#' See details for implementation notes.
-#'
-#' This method is closely related to that implemented in \code{ID}. The method is based on an incidence decay model.
-#' The estimate of R0 is the value which minimizes the sum of squares between observed case counts and cases counts
-#' expected under the model.
-#'
-#' This method is based on an approximation of the SIR model, which is most valid at the beginning of an epidemic.
-#' The method assumes that the mean of the serial distribution (sometimes called the serial interval) is known.
-#' The final estimate can be quite sensitive to this value, so sensitivity testing is strongly recommended.
-#' Users should be careful about units of time (e.g., are counts observed daily or weekly?) when implementing.
-#'
-#' @param NT Vector of case counts.
-#' @param mu Mean of the serial distribution. This needs to match case counts in time units. For example, if case counts
-#' are weekly and the serial distribution has a mean of seven days, then \code{mu} should be set to one. If case
-#' counts are daily and the serial distribution has a mean of seven days, then \code{mu} should be set to seven.
-#'
-#' @return \code{IDEA} returns a single value, the estimate of R0.
-#'
-#' @examples
-#' ## ===================================================== ##
-#' ## Illustrate on weekly data ##
-#' ## ===================================================== ##
-#'
-#' NT <- c(1, 4, 10, 5, 3, 4, 19, 3, 3, 14, 4)
-#' ## obtain Rhat when serial distribution has mean of five days
-#' IDEA(NT=NT, mu=5/7)
-#' ## obtain Rhat when serial distribution has mean of three days
-#' IDEA(NT=NT, mu=3/7)
-#'
-#' ## ========================================================= ##
-#' ## Compute Rhat using only the first five weeks of data ##
-#' ## ========================================================= ##
-#'
-#' IDEA(NT=NT[1:5], mu=5/7) # serial distribution has mean of five days
-#'
-#' @export
-IDEA <- function(NT, mu) {
- if (length(NT) < 2)
- print("Warning: length of NT should be at least two.")
- else {
- NT <- as.numeric(NT)
- TT <- length(NT)
- s <- (1:TT) / mu
-
- y1 <- log(NT) / s
- y2 <- s^2
- y3 <- log(NT)
-
- IDEA1 <- sum(y2) * sum(y1) - sum(s) * sum(y3)
- IDEA2 <- TT * sum(y2) - sum(s)^2
- IDEA <- exp(IDEA1 / IDEA2)
-
- return(IDEA)
- }
-}
+#' IDEA method
+#'
+#' This function implements a least squares estimation method of R0 due to Fisman et al. (PloS One, 2013).
+#' See details for implementation notes.
+#'
+#' This method is closely related to that implemented in \code{ID}. The method is based on an incidence decay model.
+#' The estimate of R0 is the value which minimizes the sum of squares between observed case counts and cases counts
+#' expected under the model.
+#'
+#' This method is based on an approximation of the SIR model, which is most valid at the beginning of an epidemic.
+#' The method assumes that the mean of the serial distribution (sometimes called the serial interval) is known.
+#' The final estimate can be quite sensitive to this value, so sensitivity testing is strongly recommended.
+#' Users should be careful about units of time (e.g., are counts observed daily or weekly?) when implementing.
+#'
+#' @param NT Vector of case counts.
+#' @param mu Mean of the serial distribution. This needs to match case counts in time units. For example, if case counts
+#' are weekly and the serial distribution has a mean of seven days, then \code{mu} should be set to one. If case
+#' counts are daily and the serial distribution has a mean of seven days, then \code{mu} should be set to seven.
+#'
+#' @return \code{IDEA} returns a single value, the estimate of R0.
+#'
+#' @examples
+#' ## ===================================================== ##
+#' ## Illustrate on weekly data ##
+#' ## ===================================================== ##
+#'
+#' NT <- c(1, 4, 10, 5, 3, 4, 19, 3, 3, 14, 4)
+#' ## obtain Rhat when serial distribution has mean of five days
+#' IDEA(NT=NT, mu=5/7)
+#' ## obtain Rhat when serial distribution has mean of three days
+#' IDEA(NT=NT, mu=3/7)
+#'
+#' ## ========================================================= ##
+#' ## Compute Rhat using only the first five weeks of data ##
+#' ## ========================================================= ##
+#'
+#' IDEA(NT=NT[1:5], mu=5/7) # serial distribution has mean of five days
+#'
+#' @export
+IDEA <- function(NT, mu) {
+ if (length(NT) < 2)
+ print("Warning: length of NT should be at least two.")
+ else {
+ NT <- as.numeric(NT)
+ TT <- length(NT)
+ s <- (1:TT) / mu
+
+ y1 <- log(NT) / s
+ y2 <- s^2
+ y3 <- log(NT)
+
+ IDEA1 <- sum(y2) * sum(y1) - sum(s) * sum(y3)
+ IDEA2 <- TT * sum(y2) - sum(s)^2
+ IDEA <- exp(IDEA1 / IDEA2)
+
+ return(IDEA)
+ }
+}