The title of this page is, "Unbiased estimate of population variance", but doesn't this program measure the biased estimate?

as the title says, it is about "estimating" the unbiased value using biased value. with sample sizes from 2 to 10, it shows a relation of (n-1)/n between the two, resulting in the division with the "n-1". for a sample size of 2 this is 1/2, and of 3 gives 2/3 and so on. it becomes "unbiased = biased *n/(n-1)" or simply the equation with "n-1" as the denominator.

In Population, N=463 but sample Size Vs variance has samples in thousands ?? How come it is possible?

think about how many groups (=samples) of 2, 3, 4...or 10 you could build out of 463! Lets say it would be 463 people and you build groups of 2. How many different groups could you build? Combinatorics say 463C2, which is 463*462/2 which is 106,953 possibilities. But then you can also build groups of 3, of 4... and so on. There is a lot of possibilities to build samples!

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AP®︎/College Statistics

Course: AP®︎/College Statistics > Unit 3

Lesson 5: More on standard deviation (optional)

Unbiased estimate of population variance

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UNC‑1.J (LO)

UNC‑1.J.3 (EK)

UNC‑3 (EU)

UNC‑3.I (LO)

UNC‑3.I.1 (EK)

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Jei-Cyn Kendrick
Posted 7 years ago. Direct link to Jei-Cyn Kendrick's post “The title of this page is...”
The title of this page is, "Unbiased estimate of population variance", but doesn't this program measure the biased estimate?
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(42 votes)
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- Yılmaz Durmaz
  Posted 5 years ago. Direct link to Yılmaz Durmaz's post “as the title says, it is ...”
  as the title says, it is about "estimating" the unbiased value using biased value. with sample sizes from 2 to 10, it shows a relation of (n-1)/n between the two, resulting in the division with the "n-1". for a sample size of 2 this is 1/2, and of 3 gives 2/3 and so on. it becomes "unbiased = biased *n/(n-1)" or simply the equation with "n-1" as the denominator.
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  (4 votes)
Ashik Gurung
Posted 4 years ago. Direct link to Ashik Gurung's post “So what I'm getting is th...”
So what I'm getting is that the n-1 unbiased formula describes the phenomenon where the sample variance estimate is closer to population variance using n-1 than n. However, I don't understand why this phenomenon occurs? Why does using n to divide cause an underestimation in the first place?
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(12 votes)
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Ashutosh Singh
Posted 7 years ago. Direct link to Ashutosh Singh's post “In Population, N=463 but ...”
In Population, N=463 but sample Size Vs variance has samples in thousands ?? How come it is possible?
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(2 votes)
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- Lucia Christians
  Posted 7 years ago. Direct link to Lucia Christians's post “think about how many grou...”
  think about how many groups (=samples) of 2, 3, 4...or 10 you could build out of 463! Lets say it would be 463 people and you build groups of 2. How many different groups could you build? Combinatorics say 463C2, which is 463*462/2 which is 106,953 possibilities. But then you can also build groups of 3, of 4... and so on. There is a lot of possibilities to build samples!
  Button navigates to signup page
  (14 votes)
mohale marothi
Posted 7 years ago. Direct link to mohale marothi's post “how do i find the varianc...”
how do i find the variance of classified data?
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(2 votes)
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Valerie Juma
Posted 7 years ago. Direct link to Valerie Juma's post “how do i find the varianc...”
how do i find the variance of classified data?
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(4 votes)
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konika
Posted 3 years ago. Direct link to konika's post “Can a population data be ...”
Can a population data be less than the sample data ?
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122512
Posted 3 years ago. Direct link to 122512's post “yeap this is biased one”
yeap this is biased one
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sachita chittal
Posted 3 years ago. Direct link to sachita chittal's post “Are there any places to f...”
Are there any places to find practice questions on these lessons?
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laurab549
Posted 6 years ago. Direct link to laurab549's post “In the green bar graph, w...”
In the green bar graph, what is the median?
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SA
Posted 6 years ago. Direct link to SA's post “What is this can someone ...”
What is this can someone explain?
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