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Glen_b
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Udacity claims that the fF-distribution peaks at 1, but Wikipedia has counterexamples. Which is true?

Here's a transcript of the first minute, though you may watch the video here:

The F distribution is positively skewed, meaning it peaks on the left side and is stretched off to the right side. This distribution peaks at 1. This is because if there are no differences in the population means, in other words the between group variability is expected to be 0. Then the mean of each sample will still, likely differ by chance. Since the difference, then, is due to chance. The same way that each subject in each sample differs by chance, as measured by the within-group variability. Then the between group variability and within group variability will be the same. Therefore, when we divide them we get 1. And that's where this distribution peaks.

A visit to wikipedia shows fF-distributions that do not peak at 1. Does the video use a detail that I'm not aware of to generate fF-distributions that only peak at 1? Or is the video correct (fF-distributions always peak at 1) and I'm missing a detail somewhere when looking at these fF-distributions that seemingly don't peak at 1?

Udacity claims that the f-distribution peaks at 1, but Wikipedia has counterexamples. Which is true?

Here's a transcript of the first minute, though you may watch the video here:

The F distribution is positively skewed, meaning it peaks on the left side and is stretched off to the right side. This distribution peaks at 1. This is because if there are no differences in the population means, in other words the between group variability is expected to be 0. Then the mean of each sample will still, likely differ by chance. Since the difference, then, is due to chance. The same way that each subject in each sample differs by chance, as measured by the within-group variability. Then the between group variability and within group variability will be the same. Therefore, when we divide them we get 1. And that's where this distribution peaks.

A visit to wikipedia shows f-distributions that do not peak at 1. Does the video use a detail that I'm not aware of to generate f-distributions that only peak at 1? Or is the video correct (f-distributions always peak at 1) and I'm missing a detail somewhere when looking at these f-distributions that seemingly don't peak at 1?

Udacity claims that the F-distribution peaks at 1, but Wikipedia has counterexamples. Which is true?

Here's a transcript of the first minute, though you may watch the video here:

The F distribution is positively skewed, meaning it peaks on the left side and is stretched off to the right side. This distribution peaks at 1. This is because if there are no differences in the population means, in other words the between group variability is expected to be 0. Then the mean of each sample will still, likely differ by chance. Since the difference, then, is due to chance. The same way that each subject in each sample differs by chance, as measured by the within-group variability. Then the between group variability and within group variability will be the same. Therefore, when we divide them we get 1. And that's where this distribution peaks.

A visit to wikipedia shows F-distributions that do not peak at 1. Does the video use a detail that I'm not aware of to generate F-distributions that only peak at 1? Or is the video correct (F-distributions always peak at 1) and I'm missing a detail somewhere when looking at these F-distributions that seemingly don't peak at 1?

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Glen_b
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Post Reopened by Glen_b
Less mindreading
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Why does Udacity claimclaims that the f-distribution peaks at 1, when thisbut Wikipedia has counterexamples. Which is not always the casetrue?

Here's a transcript of the first minute, though you may watch the video here:

The F distribution is positively skewed, meaning it peaks on the left side and is stretched off to the right side. This distribution peaks at 1. This is because if there are no differences in the population means, in other words the between group variability is expected to be 0. Then the mean of each sample will still, likely differ by chance. Since the difference, then, is due to chance. The same way that each subject in each sample differs by chance, as measured by the within-group variability. Then the between group variability and within group variability will be the same. Therefore, when we divide them we get 1. And that's where this distribution peaks.

A visit to wikipedia shows f-distributions that do not peak at 1. Also,Does the video only semantically explains what it meansuse a detail that I'm not aware of to have angenerate f-statistic/ANOVA value ofdistributions that only peak at 1. It does not explain why? Or is the distributionvideo correct peaks(f-distributions always peak at 1.

I would have assumed that the narrator was speaking particularly about of this randomly selected) and I'm missing a detail somewhere when looking at these f-distribution with unspecified degrees of freedom... but it seems a strange thing to emphasize. Am I missing something obviousdistributions that seemingly don't peak at 1?

Why does Udacity claim that the f-distribution peaks at 1, when this is not always the case?

Here's a transcript of the first minute, though you may watch the video here:

The F distribution is positively skewed, meaning it peaks on the left side and is stretched off to the right side. This distribution peaks at 1. This is because if there are no differences in the population means, in other words the between group variability is expected to be 0. Then the mean of each sample will still, likely differ by chance. Since the difference, then, is due to chance. The same way that each subject in each sample differs by chance, as measured by the within-group variability. Then the between group variability and within group variability will be the same. Therefore, when we divide them we get 1. And that's where this distribution peaks.

A visit to wikipedia shows f-distributions that do not peak at 1. Also, the video only semantically explains what it means to have an f-statistic/ANOVA value of 1. It does not explain why the distribution peaks at 1.

I would have assumed that the narrator was speaking particularly about of this randomly selected f-distribution with unspecified degrees of freedom... but it seems a strange thing to emphasize. Am I missing something obvious?

Udacity claims that the f-distribution peaks at 1, but Wikipedia has counterexamples. Which is true?

Here's a transcript of the first minute, though you may watch the video here:

The F distribution is positively skewed, meaning it peaks on the left side and is stretched off to the right side. This distribution peaks at 1. This is because if there are no differences in the population means, in other words the between group variability is expected to be 0. Then the mean of each sample will still, likely differ by chance. Since the difference, then, is due to chance. The same way that each subject in each sample differs by chance, as measured by the within-group variability. Then the between group variability and within group variability will be the same. Therefore, when we divide them we get 1. And that's where this distribution peaks.

A visit to wikipedia shows f-distributions that do not peak at 1. Does the video use a detail that I'm not aware of to generate f-distributions that only peak at 1? Or is the video correct (f-distributions always peak at 1) and I'm missing a detail somewhere when looking at these f-distributions that seemingly don't peak at 1?

Post Closed as "Opinion-based" by Glen_b
Post Reopened by Glen_b
Post Closed as "Needs more focus" by Glen_b
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