How can I randomly sample binomial thing?

user_16483251 0
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For example, I want to randomly line the 0, 1 (50% respectively) 10 times. So, there should be five "0" and five "1".

But, when I used:

rbinom(10,1,0.5)

sometimes, it generates four "0" and six "1".

I noticed that the sample() function has also this issue.

There should be five "0" and five "1", and the order should be at random.

binomial-coefficients simulation r
4 Answers

sample will shuffle a vector randomly. So sample(rep(c(0,1),5)) is what you need.

user_121762800

You need to use sample(), but this way:

b <- c(rep(0, 5), rep(1, 5))
sample(b)
#  [1] 1 0 1 1 0 0 1 0 0 1
sample(b)
#  [1] 0 1 1 1 0 1 0 0 0 1
sample(b)
#  [1] 0 0 0 1 1 1 0 1 0 1
sample(b)
#  [1] 0 1 0 0 1 0 1 1 0 1
user_15806450

A shortcut would be:

sample(10) %/% 6
#> [1] 0 0 0 1 1 0 0 1 1 1
user_125003150

We can use bitwAnd + sample

bitwAnd(sample(10), 1)
user_121587570
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