I have a list of chemicals, their assay test results, and a binomial column of whether or not the assay test result was high enough to be considered a threat (anything >2g/ml). Some chemicals were tested more than once, but others were not. It is understood that it is a poor set of data, but I am trying to be as useful as I can with it. I would like to take into account the variance within the same chemical.(adsbygoogle = window.adsbygoogle || []).push({});

Portion of data:

Chemical Assay reading (g/ml) >2?

A .04 0

B 1.2 0

C 4.6 1

D 1.1 0

D 2.3 1

E .03 0

F .27 0

G .92 0

G 3.00 1

G 2.34 1

H 1.36 0

I .80 0

J .45 0

K 1.75 0

L 2.45 1

L 2.60 1

M 5.6 1

N 1.11 0

O 3.14 1

P 0.50 0

Q 1.15 0

Q 2.01 1

R 1.50 0

S .09 0

T .12 0

I am trying to simply calculation the proportion where the binomial column is 1. That part is easy, but I am also trying to inclue standard error or some form of the variance. How can I take into account the variance within a chemical tested more than once?

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# Variance (error bars) with a binomial proportion

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