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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How to isolate individual contributions to group against another group?

Is there a way to compare individual team member contributions when pitted against another team multiple times? This is in a sport like rowing where you take N number of individuals from a set A and M number of individuals against set B. Is there a…
user6972
  • 143
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Sufficient Statistic for a Parameter

Show that the sum of the observations of a random sample of size $n$ from a gamma distribution that has pdf $f(x,\theta)=(1/\theta)e^{-x/\theta}$, $0
user58289
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Whats the difference between a one way anova and two way anova?

I know that in one way anova you compare the difference between two or more means and the same in two way, but I'm unclear as to how the use of categorical variables differs between them. Any help would be appreciated
bobdylan
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Statistics Olympiad Problem

Given that the mean, median, range and the only mode of 200 integers are also 200. If $A$ is the largest integer among those 200 integers, find the maximum value of $A$. I have asked some of my friends and colleagues to solve this problem, but no…
Shane Dizzy Sukardy
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Why is the standard deviation preferred over the mean deviation?

To me, the mean deviation, which is the average distance that a data point in a sample lies from the sample's mean, seems a more natural measure of dispersion than the standard deviation; Yet the standard deviation seems to dominate in the field of…
David Reed
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What does interquartile range represent (real world scenario)

I wish to understand when will i use the concept of interquartile range in real world scenario. I can understand how to calculate interquartile range but i do not understand or make sense of the final answer. For example. Below are the list of…
geo user
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What is the correct term for "growth rate of growth rate"?

Let's say a company had these monthly sales: Jan: $10$ Feb: $15$ Mar: $22.5$ The growth rate of sales would be: Jan: - Feb: $50$% Mar: $50$% What is the correct term for the "growth rate of the growth rate of sales"? e.g.: Jan: - Feb: - Mar:…
lkjerlkjase
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Find the correlation coefficient

In studying the relation between the two variables $x$ and $y$ , if the equation of the regression line of $y$ on $x$ was $$y=0.421x+0.67$$ and the equation of the regression line of $x$ on $y$ was $$x=1.58y+3.9$$ \Find\ \ The linear correlation…
Hussien Mohamed
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Cramer-Rao Lower Bound when the support for $x$ depends on $\theta$?

Are there any grounds for the following claim? For distributions for which the support in $x$ depends on $\theta$, the CRLB $=0$. For a quick example (Casella-Berger, Example 7.3.13): Let $X_1,\dots,X_n$ be iid with pdf $f(x\mid\theta) =…
NKC
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A question about $F$-distribution

Let $f(m,n,w)$ be the probability density function of $F$ variable with $m$ numerator $df$ and $n$ denominator $df$,…
TCL
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Existence of a UMP test for two binomial random variables

Let $X$ and $Y$ be independent random variables, distributed as Binomial($p, n$) and Binomial($p^2, m$), respectively. Does a UMP test (for fixed level $\alpha$) exist for: $H_0: p \leq p_0 \text{ vs. } H_1: p > p_0$? In order to invoke the…
Zoë Clark
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Ambiguity in rule for determining an outlier

I have the following set of numbers, in which I need to determine if there are any outliers: 11, 14, 21, 26, 29, 33, 61. I graphed them in Desmos (see above), and visually, it appears to me that 61 is an outlier. I searched online for a…
Phil
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Pearson's Chi Squared / Cochran–Mantel–Haenszel test analog to N-way ANOVA

A test was given to two sets of students, CONTROL and EXPERIMENT, that had question A and question B. I want to know if students who got question A right were more likely to get question B right, and I want to know if being in the CONTROL or…
mpettis
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What is the intuition behind the formula $\frac{1}{1+f(x)}$

What is the intuition of $\frac{1}{1+f(x)}$ ? I often see formulas of such style in statistics. For example sigmoid function is of form $\frac{1}{1+e^{-x}}$. Why is $\frac{1}{1+f(x)}$ used frequently? What is its intuition?
mallea
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Basic Statistical Values

I wanted to make my own problem and solve it to learn some new stuff -- Let's say we have some type of standardized test, where a rough data curve depicts $P(x)=x^2e^{-\frac{x}{14}}$ which is the number of people who got that score. Now, we have…
Saketh Malyala
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