Distribution of balls in a box (with a twist)

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    Balls Box Distribution
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Discussion Overview

The discussion revolves around the distribution of differently sized balls of two colors, red and blue, within a box. Participants explore how to describe the combined distribution of these balls, considering their size differences and the implications of these differences on the overall distribution.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants propose that the distribution of the balls can be described as a weighted average of the probability density functions (PDF) for each color, with weights based on the number of each color present.
  • Others express confusion regarding the relevance of size to the distribution, questioning how size affects the overall distribution of the balls.
  • A participant suggests that the combined distribution could be referred to as a "mixed distribution," indicating that it represents a single distribution from which a ball can be randomly selected without knowledge of its color.
  • Another participant confirms that this combined distribution is indeed a "mixture distribution," reinforcing the idea that it integrates the two color distributions into one.

Areas of Agreement / Disagreement

Participants exhibit disagreement regarding the relevance of size to the distribution and whether the combined distribution should be classified as a mixed or mixture distribution. While some participants agree on the concept of a mixture distribution, the initial confusion about the role of size remains unresolved.

Contextual Notes

The discussion does not clarify the assumptions regarding the distributions of sizes for the red and blue balls, nor does it resolve the implications of size on the overall distribution. The definitions of "mixed distribution" and "mixture distribution" are also not explicitly defined within the conversation.

Apteronotus
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Suppose I have an box (set) containing two different colored balls, red and blue, say.

Now, suppose the balls differ in size, where the size of the red balls has one particular distribution and those of the blue another.

How can we describe the distribution of the balls in the box?
 
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Your description is confusing. What has size got to do with the distribution?
 
Apteronotus said:
Suppose I have an box (set) containing two different colored balls, red and blue, say.

Now, suppose the balls differ in size, where the size of the red balls has one particular distribution and those of the blue another.

How can we describe the distribution of the balls in the box?
It's a weighted average of the PDF_red and PDF_blue, with weights proportional to the fraction of each color:

PFD_total = (num_red/total_num) * PDF_red + (num_blue/total_num) * PDF_blue
 
mathman said:
Your description is confusing. What has size got to do with the distribution?

I'm interested in the distribution of the sizes.
 
FactChecker said:
It's a weighted average of the PDF_red and PDF_blue, with weights proportional to the fraction of each color:

PFD_total = (num_red/total_num) * PDF_red + (num_blue/total_num) * PDF_blue

So would it be a "mixed distribution"?
 
Apteronotus said:
So would it be a "mixed distribution"?

It is a single distribution where a ball can be picked at random by a blind person and it would give the probability distribution of the size, without knowing the color. It combines the two distributions into one.
 
Apteronotus said:
So would it be a "mixed distribution"?
Yes. That is called a "mixture distribution".
 

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