R help - Sep 2006 - binom

I have this data and calculated binom, but am very confused with the value
(at least 5, q =4, q=5, q =6??) and parameters?  Can someone explain how to
plug in the va;ues and parameters?

    Hospital  # Tested # Positive # Positive (per 1000) A 3741 30 8 C 5006
11 2.2


If 500 newborns are screened at Hospital A, the exact binomial probability
of at least 5 HIV-positive would be:



Pr ( X >= q | X ~ Binom(size, prob))

Pr (X >=5 |X ~ Binom(500, 0.008))

pbinom(q, size, prob, lower.tail =TRUE, log.p = FALSE)
> pbinom(q=5, size=500, prob=0.008, lower.tail =TRUE, log.p = FALSE)

[1] 0.7857602

If 500 newborns are screened at Hospital C, the exact binomial probability
of at least 5 HIV-positive would be:


Pr ( X >= q | X ~ Binom(size, prob))

Pr (X >=5 |X ~ Binom(500, 0.0022))

pbinom(q, size, prob, lower.tail =TRUE, log.p = FALSE)
> pbinom(q=5, size=500, prob=0.0022, lower.tail =TRUE, log.p = FALSE)

[1] 0.9990512



thx much

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