Linked Questions

37
votes
2answers
212k views

How to interpret the output of the summary method for an lm object in R? [duplicate]

I am using sample algae data to understand data mining a bit more. I have used the following commands: ...
35
votes
7answers
6k views

Why is the null hypothesis often sought to be rejected?

I hope I am making sense with the title. Often, the null hypothesis is formed with the intention of rejecting it. Is there a reason for this, or is it just a convention?
32
votes
3answers
4k views

Is p-value a point estimate?

Since one can calculate confidence intervals for p-values and since the opposite of interval estimation is point estimation: Is p-value a point estimate?
31
votes
3answers
868 views

Accommodating entrenched views of p-values

Sometimes in reports I include a disclaimer about the p-values and other inferential statistics I've provided. I say that since the sample wasn't random, then such statistics would not strictly apply....
18
votes
6answers
5k views

Why is statistics useful when many things that matter are one shot things?

I don't know if it's just me, but I am very skeptical of statistics in general. I can understand it in dice games, poker games, etc. Very small, simple, mostly self-contained repeated games are fine....
18
votes
6answers
668 views

How to explain hypothesis testing for teenagers in less than 10 minutes?

For over a year now I've been giving a one-hour "a taste for statistics" class. Each time I get a different group of kids coming over, and I give them the class. The theme of the class is that we run ...
16
votes
4answers
6k views

Misunderstanding a P-value?

So I've been reading a lot about how to correctly interpret a P-value, and from what I've read, the p-value says NOTHING about the probability that the null hypothesis is true or false. However, when ...
14
votes
4answers
21k views

How to specify the null hypothesis in hypothesis testing

What is a good rule of thumb for how to choose the question for the null hypothesis. For instance, if I want to check if the hypothesis B is true, should I use B as the null, B as the alternative ...
11
votes
3answers
1k views

“Reversed” Shapiro–Wilk

The Sharipo-Wilk test, according to wikipedia, tests the null-hypothesis ($H_0$) "The population is normally distributed". I am looking for a similar normality test with $H_0$ "The population is not ...
11
votes
2answers
253 views

What is this trick with adding 1 here?

I was looking at this page on Lillefors test's Monte Carlo implementation. I don't understand this sentence: There is random error in this calculation from the simulation. However, because of the ...
10
votes
1answer
689 views

When can't frequentist sampling distribution be interpreted as Bayesian posterior in regression settings?

My actual questions are in the last two paragraphs, but to motivate them: If I am attempting to estimate the mean of a random variable that follows a Normal distribution with a known variance, I've ...
10
votes
1answer
238 views

How to test if “previous state” has influence on “subsequent state” in R

Imagine a situation: We have historical records (20 years) of three mines. Does the presence of silver increases the probability of finding gold in next year? How to test such question? Here is ...
9
votes
8answers
426 views

Should I trust the $p$-value in statistical tests?

I got into a debate with my supervisor over a recent paper. The test of correlation in a sample of 77 participants yielded a p-value smaller than 0.05. After removing a few participants (because later ...
9
votes
1answer
5k views

How to test the median of a population?

I have a sample of 250 units. The distribution is asymmetric. I want to test a hypothesis that the median of the population is different from 3.5, so I think a one-sample test would be appropriate. I ...
8
votes
4answers
3k views

Check if a character string is not random

Background Let's say we have an alphabet of A,B, C, D, then we look through some data and find a "word" which is DDDDDDDDCDDDDDD ...

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