Hi,
I have created two objects: object c contains yearly "distances"
between
cases and object g contains yearly interactions between cases. For each case
and every year I would like to calculate the following value:
Vit = sum(Dabt * Iait * Ibit)
Where Vit is the value of case i in year t, Dabt is the distance between all
cases a and b that have interacted more than 0 times with i, Iait is the
number of times i has interacted with a and Ibit is the number of times i
has interacted with b. So for 8027 in 1999 Vit becomes:
(0.27547644 * 1 * 2) + (0.31481129 * 1 * 1) + (0.09896982 * 2 * 1) 1.06370381
How do I create a dataframe that accomodates the values for each case in
each year? Thanks in advance!
Example:
library(zoo)
DF1 = data.frame(read.table(textConnection(" B C D E F G
8025 1995 0 4 1 2
8025 1997 1 1 3 4
8026 1995 0 7 0 0
8026 1996 1 2 3 0
8026 1997 1 2 3 1
8026 1998 6 0 0 4
8026 1999 3 7 0 3
8027 1997 1 2 3 9
8027 1998 1 2 3 1
8027 1999 6 0 0 2
8028 1999 3 7 0 0
8029 1995 0 2 3 3
8029 1998 1 2 3 2
8029 1999 6 0 0 1"),head=TRUE,stringsAsFactors=FALSE))
a <- read.zoo(DF1, split = 1, index = 2, FUN = identity)
sum.na <- function(x) if (any(!is.na(x))) sum(x, na.rm = TRUE) else NA
b <- rollapply(a, 3, sum.na, align = "right", partial = TRUE)
newDF <- lapply(1:nrow(b), function(i)
prop.table(na.omit(matrix(b[i,], nc = 4, byrow = TRUE,
dimnames = list(unique(DF1$B), names(DF1)[-1:-2]))), 1))
names(newDF) <- time(a)
c<-lapply(newDF, function(mat) 1-tcrossprod(mat / sqrt(rowSums(mat^2))))
c<-lapply(c, function (x) ifelse(x<0.000000111, 0, x))
DF2 = data.frame(read.table(textConnection(" A B C
80 8025 1995
80 8026 1995
80 8029 1995
81 8026 1996
82 8025 1997
82 8026 1997
83 8025 1997
83 8027 1997
90 8026 1998
90 8027 1998
90 8029 1998
84 8026 1999
84 8027 1999
85 8028 1999
85 8029 1999"),head=TRUE,stringsAsFactors=FALSE))
e <- function(y) crossprod(table(DF2[DF2$C %in% y, 1:2]))
years <- sort(unique(DF2$C))
f <- as.data.frame(embed(years, 3))
g<-lapply(split(f, f[, 1]), e)
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