Questions tagged [distribution-identification]

Questions about recognizing a probability distribution from a figure, formula, or text description. Please use a specific, informative title.

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55 views

Looking for a good distribution to analyse market dynamics

I'm experimenting with replacement for normal distribution for my models. So far, I tried Gamma and Inverse Gamma distributions. Gamma significantly underestimates the probability of the extreme ...
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What distribution should my data on sales follow

I'm a chain store and have many stores across the country that all sell a particular shampoo product P. I have made a plot as shown in the image below. For example, 30 stores each sold 1 of P in the ...
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3answers
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What kind of distribution is this? (Number of stones until 2 are adjacent in a game of Go)

I've plotted the histogram of the number of stones required so that 2 are adjacent when randomly placed 1 by 1 on a goban (think of a 19x19 chessboard and I place pieces 1 by 1 until 2 are adjacent, ...
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Does this distribution have a name? $f(x)\propto\exp(-|x-\mu|^p/\beta)$

It occurred to me today that the distribution $$ f(x)\propto\exp\left(-\frac{|x-\mu|^p}{\beta}\right) $$ could be viewed as a compromise between the Gaussian and Laplace distributions, for $x\in\...
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Distinguish between distributions

I have the following data frame and want to know what distribution is consistent with it. ...
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1answer
395 views

Right angled Triangular distribution

I have an empirical probability distribution which looks somewhat like a right angled triangle. I am trying to model a process which relys on a semi accurate model of this distribution. There isn't ...
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Any one knows what the distribution with density $\frac{{x{e^{ - \frac{{{x^2}}}{{2t}}}}}}{{\sqrt {2\pi {t^3}} }}$ is?

As the title, any one knows what the distribution with density $f(x)=\frac{{x{e^{ - \frac{{{x^2}}}{{2t}}}}}}{{\sqrt {2\pi {t^3}} }}$ is? Thank you!
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1answer
141 views

What distribution is this? (time until task completion and submission)

I am looking at submission data—the length of time it takes for someone to complete a flow which involves submitting an item of content. I am getting the following distributions. I have two ...
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Distribution with a given moment generating function

As a follow-up to a question on a central limit theorem for independent random variables (r.v.) here, let $Y_j=-\log(1-V_j)$, where $V_j\sim\mbox{beta}(1-\sigma,j\sigma)$, $j\in\mathbb{N}^*$, $\sigma\...
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How to determine which distribution fits my data best?

I have a dataset and would like to figure out which distribution fits my data best. I used the fitdistr() function to estimate the necessary parameters to ...
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Is there a name for this simple discrete distribution? [duplicate]

I'm just wondering if there's a name for the distribution described by the following p.m.f.: $$p(n) = n(1-s)^{n-1}s^2$$ where $n$ is an integer from $1$ to $\infty$ and $0\lt s\lt1$.
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1answer
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Modeling Smooth Decay on Logarithmic Y

I have an empirical distribution that looks like the the image below and I hoping to model it with some parametric distribution. The X axis measures "number of ...
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1answer
285 views

What is this distribution? (time-delays between two events)

I have a right-skewed distribution that has this qq-plot against a normal with the same mean and standard deviation: The data are time-delays between two events. Also, this is the histogram of the ...
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1answer
222 views

What is this distribution? $(x-1) \theta^2 (1-\theta)^{x-2}$

Does anyone know what the following distribution is, please? I can tell it is discrete and $\theta$ is somehow a probability. Thank you! $$\mathbb P_X(x; \theta) = (x-1) \theta^2 (1-\theta)^{x-2}, \ \...
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1answer
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The number of times a CI contains the true value: What distribution does this follow?

Suppose we repeat an experiment identically and independently 100 times. Each time we construct a 99% confidence interval for $\mu$ via the t-distribution. Let X = the number of times the confidence ...
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1answer
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Distribution of the ratio of dependent chi-square random variables

Assume that $ X = X_1 + X_2+\cdots+ X_n $ where $X_i \sim N(0,\sigma^2)$ are independent. My question is, what distribution does $$ Z = \frac{X^2}{X_1^2 + X_2^2 + \cdots + X_n^2}$$ follow? I know ...
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25k views

What distribution does my data follow?

Let us say that I have 1000 components and I have been collecting data on how many times these log a failure and each time they logged a failure, I am also keeping track of how long it took my team to ...
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What is the name of the distribution whose support is (0,1) and whose pdf kernel is exp(ax) - 1?

Does this probability distribution have a name? $$f_a(x) dx = \frac{a}{e^a-(a+1)} \left(e^{a x} - 1\right) dx, \quad 0 \le x \le 1.$$ Edit: I want $a$ to be positive. I don't think this is what is ...
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What are alternatives to uniform distribution when trying to fit observed data distribution? [closed]

I have a dataset of 500 observations and I have to find the best fitting distribution. If I look at the histogram of the data and the QQ plot my data seems to follow an uniform distribution. But a chi-...
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2answers
568 views

Distribution of values in a time series (tidal data)

I was trying to help my colleague with fitting a distribution curve to some empiric data (these are sea water level observations at different time points). However, I haven't succeeded since it's my ...
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3answers
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What kind of distribution is this “almost” uniformly distributed data for calls/week?

My supervisor asked me to find out which distribution represents a particular situation. I have a VoIP generator that generates calls "uniformly" distributed between callers. This means that the ...
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9answers
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How do I figure out what kind of distribution represents this data on ping response times?

I've sampled a real world process, network ping times. The "round-trip-time" is measured in milliseconds. Results are plotted in a histogram: Ping times have a minimum value, but a long upper tail. ...

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