Mathematics Stack Exchange
Mathematics Stack Exchange

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.

Statistics is the science of the collection, organization, and interpretation of data. It deals with many aspects of data, which includes the planning of data collection in terms of the design of surveys and experiments. (From Wikipedia)

More specifically, mathematical statistics is the study of statistics from a mathematical standpoint, using probability theory as well as other branches of mathematics such as linear algebra and mathematical analysis. (From Wikipedia)

For questions which are more generally about collecting and treating data, it is advised that you post your question on Cross Validated and DSSE.

37109 questions
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Hypothesis testing: how do you call the variable that is being hypothesized about?

The question is easy but it is really hard to find via Google. Say you have the following hypothesis: $H0: \mu = 0$ $Ha: \mu \neq 0 $ Now I know that $ \mu $ is called the population mean. But how do you call a variable (or value) that is…
Melvin Roest
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order statistics question 1

Let $Y1,Y2,...,Yn$ be independent, uniformly distributed random variables on the interval $[0, θ]$, $Y(k)$ the kth-order statistic, where k is an integer between $1$ and $n$. Find $E(Y(k)- Y(k-1))$, the mean difference between two successive order…
megan
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How can the Wilson Confidence Interval be adapted for more than 2 outcomes?

In this link, the Wilson Score Interval is used to calculate the interval of a discrete distribution in which possible outcomes are 1 star, 2 stars, 3 stars, 4 stars and 5 stars (this is used to calculate a score for rating items/comments on a…
u3l
  • 201
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Proving a sample mean converges in probability to the true mean

I have an i.i.d. sequence of observations $\{x_1, x_2,\ldots, x_n\}$ and I need to prove that $\frac{1}{n}\sum x_i$ converges in probability the "true mean", that it is consistent estimate of the mean. But seems to me that I already have the true…
snoram
  • 614
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Help understanding interaction and effect.

I am reading a research paper in which the authors designed three bots and wanted to determine what bot was most human-like (link is at the bottom). To do this they had subjects play against each bot and answer questions about each bots performance.…
ahahtyler
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Uncertainty in parallel resistors.

I need help with one of my study guide questions. We learned about uncertainty in class but am not sure how to attack this problem: Could someone walk me through this example? Any help will be appreciated!
user126582
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Confidence Interval within min and max values

I have set of numbers and know it's size, mean, standard deviation, minimum and maximum. When I calculate regular confidence interval for mean I get something like this (-20;50). But the source value can only be positive, so it would look bad on a…
Nickname
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Confidence Interval and margin of error

I had the following question on a study guide and was wondering if I did it correctly. I was confused because of the way the question is worded. Here is the question: And here is how I attempted it: Is this correct?? I was confused because I think…
user126582
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What is the Cumulative distribution function for random variable X?

$$ x\quad|\quad 0\quad|\quad1\quad|\quad2\quad|\quad4 $$ $$ f_x(x)\quad|\quad1/27\quad|\quad8/27\quad|\quad10/27\quad|\quad8/27 $$ Okay I want to make sure I am doing this correctly: $$ F_x(0) = P(X\leq 0) = P(X=0) = 0.0370 $$ $$ F_x(1) = P(X\leq 1)…
Tommy
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How to rank a separate population using elo points/system

Background: I have a website where students vote on the attractiveness of their peers: they are presented with two images, and they must pick one (the "winner")- then the elo score for each is updated. A user can choose to vote globally (i.e. cross…
jaredrada
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What's the proper graph representation for a category prices trends in time?

As I'm not a mathematician I thought I'd ask here for advice how to approach something I'm working on (probably a basic question for a lot of you guys, but it was a subject of a debate at my work earlier) We have this graph: and here we're trying…
Stefan29
  • 21
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Showing that the MLE of $f(x\mid\theta)=\theta x^{\theta-1}$ is consistent.

Suppose $X_1,\ldots,X_n$ are IID RV with distribution $$f(x\mid\theta)=\theta x^{\theta-1}, \;\;0
brknparticle
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Find density of the smallest value in a sample

Let $X_1, X_2,..., X_n$ be a random sample from an infinite population with density function $f(x)$ and distribution function $F(x).$ Let $Y_{(1)}$ be the smallest value in the sample (the first order statistic). Express the density of $Y_{(1)}$ in…
user111230
  • 139
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Smoothing linear graph

Which ways I can smooth data where are random fluctuations? This is linear graph of my data input: Big curves (about time 100 etc) are desirable. I already tried sliding window. Which way do you recommend?
SpeedEX505
  • 145
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How I figure what (theoretical) dice are needed to achieve a certain curve?

I am posting here by suggestion of RPG.se I want to make character stats that fit within certain bell curves depending on choices during character creation (for example race, gender, class, sprokets amount, whatever). And I am wondering how I figure…
speeder
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