I'm trying to understand why the following 2 code snippets leads to different output and I'm hoping someone can enlighten me. The second version is marginally faster - which is my motivation since this all sits in a loop, but I need to know if it is equivalent and if not then why ?
things <- 100000
n.events <- 3
probs <- rep(0.05, n.events)
# Method 1
set.seed(1)
events1 <- matrix(n.events, nrow=things)
events1 <- sapply(probs, function(probs) rbinom(things,1,probs))
# Method 2
set.seed(1)
events2 <- matrix( rbinom(things*n.events, 1, probs), ncol=n.events, byrow=TRUE)
> identical(events1, events2)
[1] FALSE
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