In probability theory and statistics, the binomial distribution with parameters n and p is the discrete probability distribution of the number of successes in a sequence of n independent yes/no experiments, each of which yields success with probability p. (Def: http://en.m.wikipedia.org/wiki/Binomial_distribution)
Questions tagged [binomial-distribution]
2213 questions
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binomial distribution - solve for p
Given an undirected Graph with $n$ nodes. I want to create edges between two nodes with a probability $p$ so that every node has on average 2 edges. How do I calculate $p$?
I know that to calculate the average number of edges given $p$ I can…
heth
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Binomial distribution of $P(x>8)$
how do I do binomial distribution of $P(x>8)$, given $X\sim B (10,0.3)$
lets say for $P(X\ge2) = 1- p(X=0) - P(x=1)$
why is $P(x>8) = P(x=9) + P(x=10)$, how did this come about and why i cant do the same as above?
user185692
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Combining Cumulative Binomial Probabilities? with simple change in probability?
Greg can hit a free throw 85% of the time.
Greg can hit a three-pointer 45% of the time.
Greg enters a contest that involves shooting 15 free throws and 5 three-pointers.
Each attempt is either a basket or a miss.
What is the probability Greg makes…
Alix Sunder
- 11
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Binomial Distribution question based on n bit string
I was studying the binomial distribution and found this question below
A random bit string of length n is constructed by tossing a fair coin n times and setting a bit to 0 or 1 depending on outcomes head and tail, respectively. The probability that…
user3767495
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Probable a Binomial Probability Problem :) (not sure)
I need to calculate the average profit in a month of a trading strategy.
My probability of a successful trade is 33%
My probability of a bad trade is 67%
The strategy has a Risk Return ratio of 1:3 meaning that I risk 1 to gain 3
So in a bad trade I…
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Discrepancy between sum marginal distributions of multinomial distribution, and sum of binomial distributions
I have a question which says two discrete random variables $X, Y$ have joint probability function
$$
f(x,y) = {n\choose {x, y, n-x-y}}p^xq^y(1-p-q)^{n-x-y}
$$
Then the question asks for the distribution of $T = X+Y$. It is easy to see that $T$…
user3002473
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Binomial Probability with Tetrahedron
Question:
What I tried. Well for part i the probability of any face being landed on is 1/4.
I'm not sure if the way I explanation for the approach I took is correct because it gets the same answer but...
$$ {\binom {3}{3}}*({\frac 1 4} )^3$$
My…
D.Ronald
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Recurrence relation for binomial CDF
The binomial PMF (probability of exactly k successes in n trials with probability p)
$$f\left( {k,n,p} \right) = {{n!} \over {k!\left( {n - k} \right)!}}{p^k}{\left( {1 - p} \right)^{n - k}}$$
And the recurrence relation for an additional success…
shg
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Confused about using normal approximation to binomial
I am dealing with a problem similar to what is described in Problem involving normal approximation to the binomial..
Assume that 30% of adults are smokers. Let $X$ be the number of adults in a random sample of size $n=100$. Use the normal…
JoeyNYC
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Binomial distribution and probability of items needing repair
I have the following problem:
A manufacturer knows that on average 20% of the TVs it produces will need repair within a year. Suppose that 20 TVs are randomly selected and let $X$ be the number of TVs that will require repair.
Find then number $x$…
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Expected value of a Binomial distribution where x~bin(25, 0.2)
This is an example from the text I'm using but I just want to make sure that I'm not going crazy here.
A multiple choice exam consists of 25 questions each with five choices with
once choice is correct. Randomly select an answer for each question.…
Heavenly96
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Difference of two binomial random variables with identical distribution
Is there a closed form answer for absolute value of difference of two identical binomial random variables with identical distributions when $p=1/2$?
In particular, what is the the distribution of $|X-Y|$ when $X$ and $Y$ are independent and both…
Sepehr
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Binomial probability, p not given
If you Google “Binomial probability word questions,” you find a bunch of questions like this one: If a coin has a 50% chance of flipping H on a single flip, what’s the probability that it will do so in exactly 3 out of 4 flips? That question is…
Chaim
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Find CDF of Z = min(X,Y)
Conditions
1) Two random variables X, Y are independent and they follow binomial distribution with probability of success p.
2) X's mean is 2 and so does Y.
The question is to find the CDF of Z=min(X,Y)
I have no idea how to solve this question. I'm…
Joy
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A more general Poisson Binomial Distribution
The Poisson Binomial Distribution is the discrete probability distribution of a sum of independent Bernoulli trials that are not necessarily identically distributed. The first four moments of this distribution are shown in the figure (source:…
user120911
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