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Questions tagged [binomial-cdf]

58 questions
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10 answers

How can I efficiently calculate the binomial cumulative distribution function?

Let's say that I know the probability of a "success" is P. I run the test N times, and I see S successes. The test is akin to tossing an unevenly weighted coin (perhaps heads is a success, tails is a failure). I want to know the approximate…
sanity
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Calculating the probability of system failure in a distributed network

I am trying to build a mathematical model of the availability of a file in a distributed file-system. I posted this question at MathOverflow but this might as well be classified as a CS-question so I give it a shot here as well. The system works…
Yrlec
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Beta Binomial Function in Python

I would like to calculate the probability given by a binomial distribution for predetermined x(successes), n(trials), and p(probability) - the later of which is given by a probability mass function Beta(a,b). I am aware of…
TheChymera
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Julia, function to replicate "rbinom()" in R

I have dug around and googled but not found an example. I'm sure Julia has a powerful function (in base?) to generate random binomial (bernoulli?) "successes" with a given probability. I can't find it or figure out how to do the equivalent to in…
Jim Maas
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Fit beta binomial

I have been looking for a way to fit data to a beta binomial distribution and estimate alpha and beta, similar to the way the vglm package in VGAM library does. I have not been able to find how to do this in python. There is a scipy.stats.beta.fit()…
user3266890
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Binomial coefficient

'Simple' question, what is the fastest way to calculate the binomial coefficient? - Some threaded algorithm? I'm looking for hints :) - not implementations :)
Skeen
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R binom.test roundoff error?

I’m confused about the operation of binom.test. Say I want to test a sample of 4/10 success against p=0.5. The P value should be: P(X <= 4) + P(X >=6) or P(X <= 4) + 1-P(X <= 5) and indeed: >pbinom(4,10,p=0.5) + 1-pbinom(5,10,0.5) [1]…
turtlegraphics
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Discrete probability distribution calculation in Matlab

I have given P(x1...n) discrete independent probability values which represent for example the possibility of happening X. I want a universal code for the question: With which probability does happening X occur at the same time 0-n times? For…
Clemens
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rbinom; How to ensure at least one "success" is returned?

Is there a way to ensure rbinom() returns at least one success? I am running rbinom() with a really low probability: rbinom(5015, size=2, prob= 1/5000)) Since it is a probability distribution, there is a chance all 0s are returned. Is there a way…
Sky Scraper
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Binomial test in Python vs R

I am trying to re-implement a binomial test initialy developed in R with Python. However, I am not sure if I am using the right functionality. In R, I get: > binom.test (2, 8, 11/2364, alternative = "greater") 0.25 With Python & SciPy, I use from…
El Dude
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How do I find "prob=?" in this equation pbinom(q=5,size=10,prob=?,lower.tail=FALSE)=.1?

How do I solve for the "prob=" parameter of pbinom() if I want pbinom() to equal a specific value and I assume values for "q=" and "size=" parameters? Let's assume that I want pbinom() to equal 0.1 when I have q=5, size=10, and lower.tail=FALSE, is…
Ursus Frost
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Efficient sampling from a 'partial' binomial distribution

I am want to sample from the binomial distribution B(n,p) but with an additional constraint that the sampled value belongs in the range [a,b] (instead of the normal 0 to n range). In other words, I have to sample a value from binomial distribution…
Black Jack 21
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Is there a way to find the probability p with R for pbinom

I think this is a rather common problem, but I could not find a solution. I want to solve the following equation: pbinom(18,25,p)=0.05. Is there a way to find the unknown p with the program R? Every help is appreciated.
garondal
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How to generate random number 1 & 2 instead of 0 & 1 from binomial distribution?

I would like to generate random number from binomial 1 or 2 instead of the usual 0 and 1. Normally we will use rbinom(10, 1, 0.4) to generate either 0 or 1, but is it possible to generate 1 and 2? Or is there any way to convert it?
Elvis
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brms family binomial: Weird behavior with trials in formula? Error: ... requires integer responses

In R's glm() function you can fit a logistic regression (with family = binomial) by using a "column specification" of the response variable like so: glm(cbind(success, (n - sucess)) ~ 1, family = binomial, ...) The documentation of brmsformula…
MrMax
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