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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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assigning items of a list to the nodes of a graph

I want to assign items of a list to the nodes of a graph one by one as attributes of those nodes. The code is as follows but it doesn't loop through the second "for". How can I fix this? r = bernoulli.rvs(p=0.4, size=100) G =…
p a a
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Linear regression to fit a power-law in Python

I have two data sets index_list and frequency_list which I plot in a loglog plot by plt.loglog(index_list, freq_list). Now I'm trying to fit a power law a*x^(-b) with linear regression. I expect the curve to follow the initial curve closely but the…
StijnVanDijk
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Problem with r2 value of power law fit: Is this fit really worse than a straight line?

I have a dataframe of x and y data. The data exhibit a general power law form so I would like to fit a curve that's a power law. However when I do so I get a r2 value of -2.63 which tells me that the fit is worse than a straight line would be. Is…
JAG2024
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generate scale free network with power-law degree distribution by python

I write this code to generate scale free network with power law degree distribution. import networkx as nx import random N = 1000 exponent = 2.2 test = [int(random.paretovariate(exponent-1)) for i in range(N)] graph =…
Atefeh Rashidi
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Power law distribution fitting in Python

I am using different python to fit density functions on a dataset. This data set is made of positive time values starting from 1 second. I tested different density functions from scipy.statistics and the powerlaw library, as well as my own functions…
rhcpps
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Fitting power law for income distribution

I am working with micro-data on total net household income for different countries and before computing inequality indexes, I want to adjust the right tail to take into account the sensitivity of these indexes to top incomes and top-missing.…
Luca Giangregorio
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How to fix "Error in m$getDat() : attempt to apply non-function" when estimating xmin for poweRlaw

I'm trying to fit a power law distribution to some sample data. I am trying to find xmin using the estimate_xmin() function. Does anyone know why I get an error about attempting to apply a non-function? abs.logreturns <-…
sam.1992
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Levy walks / power law distributions using Unity / C#

I'm wanting to create some AIs with a Levy flight based random walk. I've currently got them moving with a completely random walk (random distance between a min and max value, and random waiting time between a min and max value). I'm aware that Levy…
Brownbird
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Fitting data using broken power-law in gnuplot

I want to fit my data with broken power law function. I am using data from two different files and this is the code that I am using to fit my data in gnuplot tool set term wxt p 'Data1.dat' u 1:($8*100):2:($9*100) w xyerr lt 7 t '', \ …
Arya Stark
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Can we find out if a distribution is following a power law distribution by using a qqplot ( using R)?

I want to find out if a given distribution follows a power law. My question is, can we use a qq plot to do this? I first estimate the xmin by integrating over the entire dataset. Following which, I found alpha using MLE. (xmin and alpha are…
Piyush Gupta
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Pandas: How to split a column of a dataframe, which follows powerlaw into two based on frequency distribution?

I have a data frame of 1 million records with 5 columns. unique_index,name,company_name,city_id,state_id Column, company_name, has 100k unique records. This follows a power law. Top 5000 company_names cover 70% of the records. I want to take equal…
pnv
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Curvefitting for power law function y= a(x^b)+c

I am new to MATLAB, and I am trying to fit a power law through a dataset. I have been trying to use isqcurvefit function, but I am unsure how to proceed as the instructions found through Google are too convoluted for a beginner. I would like to…
Tom
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powerlaw Python package errors

I'm currently trying to fit a set of (positive) data with the powerlaw.Fit() function from the powerlaw package. However, every single time I do this I obtain the following message: which I've been trying to figure…
Jayjay95
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power-law curve fitting scipy, numpy not working

I came up with a problem in fitting a power-law curve on my data. I have two data sets: bins1 and bins2 bins1 acting fine in curve-fitting by using numpy.linalg.lstsq (I then use np.exp(coefs[0])*x**coefs[1] to get power-law equation) On the other…
Sina
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Fit power law using scipy minimize

I want to do maximum likelihood estimation using scipy minimize for a function of the form y = a * x^b where the errors are assumed to be normally distributed around the predictions. Currently, the true parameters cannot be recovered at all (see…
beginneR
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