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Questions tagged [power-law]

A power law is a functional relationship between two quantities, where one quantity varies as a power of another.

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Random number generator that produces a power-law distribution?

I'm writing some tests for a C++ command line Linux app. I'd like to generate a bunch of integers with a power-law/long-tail distribution. Meaning, I get a some numbers very frequently but most of them relatively infrequently. Ideally there…
twk
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Fitting a curve to a power-law distribution with curve_fit does not work

I am trying to find a curve fitting my data that visually seem to have a power law distribution. I hoped to utilize scipy.optimize.curve_fit, but no matter what function or data normalization I try, I am getting either a RuntimeError (parameters…
kpax
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python plot and powerlaw fit

I have the following list: [6, 4, 0, 0, 0, 0, 0, 1, 3, 1, 0, 3, 3, 0, 0, 0, 0, 1, 1, 0, 0, 0, 3, 2, 3, 3, 2, 5, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 2, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 2, 0, 0, 0, 2, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1,…
Tasos
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Fit a power law to empirical data in Python

I'm experimenting with fitting a power law to empirical data using the powerlaw module. I have created the following data that follows a power law distribution of exponent 2: x = range(1,1000) y = [] for i in x: y.append(i**(-2)) I'm expecting…
Moses Xu
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Correct way to standardize/scale/normalize multiple variables following power law distribution for use in linear combination

I'd like to combine a few metrics of nodes in a social network graph into a single value for rank ordering the nodes: in_degree + betweenness_centrality = informal_power_index The problem is that in_degree and betweenness_centrality are…
Jacob Rigby
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Linear regression in R (normal and logarithmic data)

I want to carry out a linear regression in R for data in a normal and in a double logarithmic plot. For normal data the dataset might be the follwing: lin <- data.frame(x = c(0:6), y = c(0.3, 0.1, 0.9, 3.1, 5, 4.9, 6.2)) plot (lin$x, lin$y) There I…
R_User
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Python power law fit with upper limits & asymmetric errors in data using ODR

I'm trying to fit some data to a power law using python. The problem is that some of my points are upper limits, which I don't know how to include in the fitting routine. In the data, I have put the upper limits as errors in y equal to 1, when the…
astrostudent
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How to properly fit data to a power law in Python?

I am considering the number of occurrence of unique words in the Moby Dick novel and using the powerlaw python package to fit words’ frequencies to a power law. I am not sure why I can't recapitulate the results from previous work by Clauset et al.…
0x90
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How to perform a joint fit of several curves (in Python)?

Suppose I'm fitting some data points by a simple linear regression. Now I'd like to perform several joint linear regressions for several sets of data points. More specifically, I want one parameter to be equal among all fits, which is schematically…
Beaker
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Zipf's Law in Java for text generation - too slow

Hey there I'm working on a textgenerator, that should generate millions of different texts. to make the content of each text realistic I used Zipf's Law It is working well, the word distribution is correct. But the following next() function is…
Any1
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python scipy stats pareto fit: how does it work

... help and online documentation say the function scipy.stats.pareto.fit takes as variables the dataset to be fitted, and optionally b (the exponent), loc, scale. the result comes as triplet (exponent, loc, scale) generating data from the same…
0range
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How can I generate a sample from a log-normal distribution with Pareto tail in R?

I would like to generate a sample from a log-normal distribution with Pareto tail in R. Can somebody help me? Thanks.
stochazesthai
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Multiple power law plots with package poweRlaw

I tried using the package poweRlaw to plot a few powerlaw fits. It seems working for a single curve. But I could not plot multiple plots on the same graph. Ref: Is there a way within this package? [P.S. I am a novice] set.seed(1) x1 <-…
Attu nonUser De
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Comparing Power Law with other Distributions

I'm using Jeff Alstott's Python powerlaw package to try fitting my data to a Power Law. Jeff's package is based on the paper by Clauset et al which discusses the Powerlaw. First, some details on my data: It is discrete (word count data); It is…
born to hula
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Fitting a power law for extrapolation

I am trying to figure out how to interpolate a function, and I want to be able to extrapolate a small way beyond the interpolation range. There is some background theory which leads me to expect that the behavior for large values of the dependent…
лаетековский чайник
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