Questions tagged [statistics]
Mathematical statistics is the study of statistics from a mathematical standpoint, using probability theory and other branches of mathematics such as linear algebra and analysis.
11,528
questions with no upvoted or accepted answers
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Does exponential distribution affect my solution?
I was struck at the beginning that it was dealing with the exponential distribution, but as I got the answers, it was nothing to do with the exponential distribution. so I can just ignore the "...
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Write conclusion
How can i write finding and conclusion after caculating the result of standard deviation? I can caculate the standard deviation question properly, but i can't write the finding on this question. I ...
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Joint normal and exponential
if X has exponential exp(lambda)and Y has normal distribution N(0,1) . X and Y are independent. how can one find p(X < Y)?
My thoughts were to integrate :
$$\int_{-\infty}^{+\infty} F_X(y)f_Y(y) \...
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Help understand likelyhood function notation?
I'm reading An Introduction to Statistical Learning book and I've been struggling to understand this product notation. The usual form was $\prod_{i=1}^nx_i$.
...
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500 seats, how many visits before it is more likely than not that you will sit on the same seat as for one of your earlier visits?
A theatre has 500 seats and you buy tickets randomly. How many times do you need to visit the theatre before it is more likely than not that you will sit on the same seat as for one of your earlier ...
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A Geometric Distribution Question
Messages relayed over a communication channel have probability p of being received correctly. A message that is not correctly is retransmitted until it is. What value should $p$ have so that the ...
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Geometric Random Variable problem help.
$X$ is a geometric random variable with $p = 0.1$. Find:
$$a. F_X(5)$$
$$b. Pr(5 < X \leq 11)$$
$$c. Pr(X=7|5<X\leq11)$$
$$d. E(X|3<X\leq11)$$
$$e. E(X^2|3<X\leq11)$$
$$f. Var(X|3<X\...
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1
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MLE question given bionomial
I'm not exactly sure how to go about this question.
Among $N$ $i.i.d.$ observations on a $Binomial(2,p)$ random variable, $N_0$ takes on the value 0, $N_1$ takes on the value 1 and $N_2$ take on the ...
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Binomial distribution question - solving for p
If $X \sim \operatorname{Binomial}(2,p)$, find a value of p for which $Pr(W=4)=0.3432$, where $W=(X+1)^2$
My thought process:
Find $X$ when $W=4$,
$$4=(X+1)^2$$
Therefore $X=1$
Then solve ...
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1
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Expectation of Matrix's Determinant
I have an issue about find expectation of deteminant
Give a symmetric matrix, It has tree entries which is uniform random variable U(-60;60). Find expectation of Matrix's determinant
Please help me. ...
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How to find the percentage of $\bar{X}\pm S$?
How to find the percentage of $\bar{X}\pm S$ in the table
The solution is given as
then
the percentage is
My question is where does the equation
come from?
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MLE of a Normal Distribution
Consider independent random variable $Y_1,Y_2,\dots, Y_n$ and known real numbers $x_1,x_2,\dots x_n$. The distribution of $Y_i$ is Normal with mean zero and variance $\sigma^2/x_i^2$, where $\sigma^2$ ...
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How would one find the sum of the following question using poisson properties?
I don't really have any idea how to approach this question. I can't manipulate it to resemble poisson.
$\sum_{x=0}^{\infty}\frac{2^x}{x!}$
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How do I calculate mean and sd with only such information provided?
Question
If ππ=ππ+0.25ππ and ππ and ππ are independent random variables that are formulated to be normally distributed with ππβΌππ(πππ₯π₯,πππ₯π₯) and ππβΌππ(πππ¦π¦,πππ¦π¦),
(a)...
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Figuring out a conditional probability question with an answer that doesnβt make sense
Here is the question:
A contractor is hired for the job of paving streets and roads, in the end if the quality of pavement is approved by quality assessments, the contractor's work is accepted.
We ...
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