Linked Questions
18 questions linked to/from Regarding p-values, why 1% and 5%? Why not 6% or 10%?
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What is a good P value for statistical significance when conducting a Wilcoxon Rank Sum test? [duplicate]
Is a P value of 0.4 statistically significant for a Wilcoxon Rank Sum test?
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Reason behind the choice of the 0.05 p-value threshold value [duplicate]
I just would like to understand the basis and rational why 0.05 is widely used as the accepted value to decide rare or unlikely.
Is p-value threshold related with the confidence interval or +/- $2\...
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Who decided that p value should be less than 0.05 and why? [duplicate]
In many scientific fields, a p value less than 0.05 is considered significant, pointing to real difference in reality, whereas anything above it cannot be accepted (i.e. null hypothesis cannot be ...
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Famous statistical quotations
What is your favorite statistical quote?
This is community wiki, so please one quote per answer.
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What are some examples of anachronistic practices in statistics?
I am referring to practices that still maintain their presence, even though the problems (usually computational) they were designed to cope with have been mostly solved.
For example, Yates' ...
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Is the exact value of a 'p-value' meaningless?
I had a discussion with a statistician back in 2009 where he stated that the exact value of a p-value is irrelevant: the only thing that is important is whether it is significant or not. I.e. one ...
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Is p=5.0% significant?
Today I was asked, whether a p-value of 0.05 (exactly) is considered significant (given alpha=5%) or not. I did not know the answer and Google turned up both answers: (a) the result is significant if ...
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Number of trials required from a binomial distribution to get the desired odds
This question may have been asked before, but I couldn't find it. So, here goes.
From about 3000 data points that can be characterized as "wins" or "losses" (binomial), it turns out that there are ...
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Why is usually the acceptable probability of type 1 and type 2 errors different?
This question is raised by my supervisor and I don't know how to explain.
Usually the accepted confident level is 0.95 which means that the probability of type 1 error is 5%. But the usually ...
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3
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Paired t-test to support increase in student reading scores from fall to spring
I did a pre-test, post-test method and I tried to perform a t-test to show how reading scores increased from fall to spring.
I’m not sure if my numbers are accurate.
What throws me off is the NULL ...
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Chi-square origin of the name
What are the origins of the names and letters in these distributions:
What is the origin of the name in chi-square distribution $\chi_k^2$?
And the origin of $t$ in student's $t$-test?
And naming $...
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Clinical trials significance
I have been a studying high energy physics (HEP) for the last few years but I recently started working on a project in medical imaging. I have been a little surprised (not entirely I was aware that 95%...
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how to apply bootstrapping in this case?
I have a small sample of marks obtained by a group of students and I would like to apply a binomial test to check if more than half of the size of the classroom has failed due to the application of a ...
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Optimal approach to independence check
I want to see if a vendor is biased against one type of vehicle compared to another.
I have two categories of vehicles: OWN and T/C.
The vendor sells fuel to these vehicles.
The process is as ...
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What is significant?
There is a widespread notion that a p-value less than 0.05 is to be considered statistically significant, and above, not so.
I understand that the "0.05" was an arbitrary number, albeit arbitrated by ...
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