Questions tagged [distribution-identification]

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

32 questions with no upvoted or accepted answers
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8
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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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315 views

Distinguish between distributions

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

What distribution has the p.d.f. of form $\frac{e^{-b \cdot x} \cdot x^c}{1 + e^{-k \cdot (x+a)}}$ for $x >0$ and parameters $b > 0, k > 0, c > 0$?

In my work I met the p.d.f. of form $$p(x) \propto \frac{e^{-b \cdot x} \cdot x^c}{1 + e^{-k \cdot (x+a)}}$$ with support $x \in [0, +\infty)$ and positive parameters $b > 0, k > 0, c > 0$. ...
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74 views

Is this a known distribution?

For work, I plotted a set of shops by how many times they did business in the past week. The plot I got out looked something like this: This looked obviously like a Pareto distribution. After all, ...
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28 views

What's the name for a distribution where at the extreme there are more values farther away from the mean than closer?

The image below from this blog provides a good example. I'm talking about distributions that are roughly Gaussian except that there are more values at the high end that would be expected. In ...
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209 views

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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31 views

What probability distribution would be look like this?

I was playing with R, I started with adding consecutive binomials (the n parameter of the second binomial variable depends of the result of the first binomial and so on...). After a few more ...
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22 views

Identifying the best fitting distribution type to test

Hi I tried to analyze a dataset, of USDT concurrency and following is the frequency distribution I received for log return I need this dataset to fit for a particular distribution. Can we suggest ...
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41 views

Identifying the distribution of this data

I'm working with a datetime series, and each observation is the count of occurrences per that period. This sounds to me like these values would be Poisson distributed. But my EDA has left me ...
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56 views

What is the distribution of this Random Variable? I am expecting a Chi-Squared, but there is one term which is extra

I am trying to find the distribution o random variable $H$, but I am somehow confused. The assumption is $M$ and $N$ are large enough (maybe around $100$). When $L=1$, the distribution of $H$ is a ...
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64 views

Identify the underlying distribution from multiple samples

I have $30$ unequal samples ($n_i >1000$) from a supposedly same population. How should I go about identifying the underlying distribution of the population using these $30$ samples simultaneously? ...
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27 views

Distribution of relative proportions of draws from two uniform distributions

Drawing samples from 2 uniform distributions and calculating pairwise proportions of drawn values gives rise to a distribution I cannot recognize. What distribution is this? ...
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141 views

Determining the distribution of data

Hi, I am a student learning financial modelling. I would like some help in determining the distribution of the data given the plots above. I am reluctant to assume normal distribution of the data due ...
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295 views

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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1answer
53 views

What distribution is $P_X(x \mid K, N) = \frac{1}{ ( 1 + N)^K} {x + K -1 \choose x} \left( \frac{N}{1+N}\right)^x$?

What kind of distribution is the following: $$ P_X(x \mid K, N) = \frac{1}{ ( 1 + N)^K} {x + K -1 \choose x} \left( \frac{N}{1+N}\right)^x $$ and how can I find $P_X(x < x_0 \mid K, N)$?
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38 views

Does anyone recognize this probability distribution?

Can someone tell me what distribution/ family of distributions is this?
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36 views

How to choose and plot the most appropriate distribution in R?

I need to choose the distribution that best fits my data for different datasets. There are similar discussions here and here, but I am still struggling to find proper solution. My first attempt was ...
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20 views

Help selecting a correct distribution for this data

I'm a geologist working with some sparse borehole data. The boreholes sample igneous intrusions and we're trying to fit a distribution to the thickness of the intrustion vs frequency (for use in other ...
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1answer
37 views

Help finding the type of distribution

I am doing a question which involves the following probability density function $$f(x;\mu,\lambda) = \sqrt{\frac{\lambda}{2\pi x^{3}}} exp\bigg(\frac{-\lambda(x-\mu)^2}{2\mu^2x}\bigg), x>0, \lambda,...
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35 views

What distribution could the data stem from?

From checking the histogram of the distribution I had the intuition that the data could follow a Poisson or an exponential distribtuion. However, Lilliefors test that the data is exponentially ...
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22 views

Test for statistical distribution

I'm new to statistical analysis and I'm trying to identify which distribution fits my BD better. My BD has length of stay (LOS) data in two different hospitals: ...
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65 views

Is there a way to find a statistical distribution for the below data?

Is there a way to find a statistical distribution for the below data? This is derived from frequency count of different topics in a large corpus of news stories. I wonder if this follows a Poisson ...
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58 views

QQ plot distribution check

I want to check if a distribution is log normal or not by using qq plot. So for convenience I am creating a lognormal distribution using stats and checking it in ...
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41 views

Are there any methods to test whether a data set obeys a certain probability distribution?

If one has a set of data, are there any methods or techniques of testing whether that set obeys a candidate distribution? I have thought of a number of possibilities: Simply histogram and look at it, ...
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30 views

How can I identify an unfamiliar cumulative distribution function?

I have 116 Bessel-corrected sample variances (average of squared distances from sample mean), each from a sample of three measurements. All measurements were done using the same method. I had ...
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1answer
343 views

Compare distribution to given shapes to find the most similar

I have a multiple comparison problem between some thousands of correlation distributions and given shapes. I have computed pair-wise correlation for a given set of gene expresion data, and I have ...
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65 views

How can i find a suitable distribution that fits my data?

I have some data on prevalence of a given infection, provided for each country for 6 different age groups. I am trying to find a suitable distribution that may be suitable to model capture the ...
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50 views

To what distribution it's similar? Looks like an exponential but it's not

To what distribution it's similar? Looks like an exponential but it's not. It's seems to have a property, that if I zoom it (xlim) then each time it has the same ...
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813 views

If this is a log normal distribution, how can I fit it?

The qualified question title hints at my not being certain as to what I'm really dealing with. I have some truly random samples that generate the following graph. This is just a small extract and ...
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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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64 views

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
394 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 ...