Normal and power law distributions

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SUMMARY

Independent random events lead to a normal distribution when summed, while dependent random events result in a power law distribution when multiplied. The discussion illustrates this concept through a practical example using a spreadsheet to generate random numbers, where sums and products of these numbers are calculated, sorted, and graphed. The hypothesis is that as the number of random events increases, the distribution of sums approximates a normal distribution, while the distribution of products approximates a power law distribution. This observation is supported by the frequency analysis of the generated data.

PREREQUISITES
  • Understanding of basic statistics, specifically distributions
  • Familiarity with random number generation techniques
  • Proficiency in using spreadsheet software for data manipulation
  • Knowledge of sorting algorithms and frequency distribution analysis
NEXT STEPS
  • Explore the Central Limit Theorem and its implications on normal distributions
  • Learn about power law distributions and their applications in various fields
  • Investigate advanced statistical software tools like R or Python for data analysis
  • Study the concept of binning in histograms and its effect on distribution visualization
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Statisticians, data analysts, mathematicians, and anyone interested in understanding the behavior of random events and their distributions.

erszega
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Is it correct to say that independent random events (additively) lead to a normal distribution, and dependent random events (multiplicatively) lead to a power law distribution?

The following might be trivial, but it was quite interesting to find for me, someone with a very limited knowledge of mathematics or statistics:

Take a matrix of random numbers r(i,j), where 0 < r(i,j) < 1.

Let S(i) = int( ( r(i,1) + r(i,2) +...+ r(i,j) )*n ), with S(i) >= S(i-1) if i >= i-1, that is, S is a sorted list of the integer parts of the sums of random numbers multiplied by an integer.

Let P(i) = int( ( r(i,1) * r(i,2) * ... * r(i,j) )*n ), with P(i) >= P(i-1) if i >= i-1, that is P is a sorted list of the integer parts of the products of random numbers multiplied by an integer.

Hypothesis (based simply on observation of graphs of S(i) and P(i)):

the higher the values of i and j, the more S(i) approximates normal distribution, and P(i) approximates a power-law distribution.

Is this right?
 
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Apologies, I meant the frequency of each S(i) or P(i).
It may be better to describe what I did in the following way:
I used a spreadsheet, and created a table, consisting of, say, 10,000 rows and 5 columns, of random numbers (using the spreadsheet's random number function). Then I added (or multiplied) the random numbers in each row. I multiplied the sums (or products) by, say, 100, and took the integer parts (to create "bins"). Then I sorted the "bins", calculated the frequency (number of occurencies in the list) of each "bin", and then put a graph on the frequency list. I hope this makes sense.
 
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