1 files changed, 30 insertions, 0 deletions
diff --git a/R/computeLL.R b/R/computeLL.R
new file mode 100644
index 0000000..0730399
--- /dev/null
+++ b/R/computeLL.R
@@ -0,0 +1,30 @@
+#' WP method background function computeLL
+#'
+#' This is a background/internal function called by \code{WP}.  It computes the log-likelihood.
+#'
+#' @param NT vector of case counts
+#' @param p discretized version of the serial distribution 
+#' @param R0 basic reproductive ratio
+#' @return The function returns the variable \code{LL} which is the log-likelihood at the input variables and parameters.
+
+#' @export
+# 
+computeLL	<-	function(p, NT, R0){
+
+	k		<-	length(p)
+	TT		<-	length(NT)-1
+	mu_t	<-	rep(0, TT)
+	for(i in 1:TT){
+		Nt		<-	NT[i:max(1,i-k+1)]
+#		print(Nt)
+#		print(p[1:min(k,i)])
+		mu_t[i]	<-	sum(p[1:min(k,i)]*Nt)	
+	}
+	mu_t	<-	R0*mu_t
+	LL		<-	-sum(mu_t)+sum(NT[-1]*log(mu_t))
+
+	return(LL)
+	
+}
+
+