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 ...
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....
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 ...
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 ...
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....
670 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 ...
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 ...
782 views

### What is this equation (pictured) called?

Could someone provide some Google-able words for this equation? $$Q_{\chi^2,d} = \left[2^{d/2}\Gamma\left(\frac{d}{2}\right)\right]^{-1}\int_{\chi^2}^\infty (t)^{\frac{d}{2}-1}e^{-\frac{t}{2}}dt$$ ...
31k views

### Why does the p-value double when using two-tailed test compared to one-tailed one? [duplicate]

Since this has been marked as a duplicate, I want to clarify that it's not about critical values of one- vs two-tailed tests, but the calculation of the p-Value in this case. I get that in a two-...
23k views

### P-value vs Type 1 Error [duplicate]

I am trying to understand the relationship of a p-value vs Type 1 error rate. My understanding of one interpretation of a p-value is the following: "the p-value tells us the probability of making a ...
5k views

### Is “Confidence Level” just 1 minus P-Value?

If the results of a Chi-Square test give a P-Value of 0.01 then can we say that the confidence level in their being a difference is (1-0.01) = 99% confidence. Background. We are conducting website ...
16k views

### Pearson correlation coefficient test: low $r$ and low p-value

I am running a correlation coefficient test, and the results were: $r = 0.382, p = 2.76 \times 10^{-13}$. So the $r$ value is not that impressive (usually we see $r>.5$), but the $p$-value is ...
18k views

### Confused about region of rejection vs P-value.

What exactly is the difference between the Region of Rejection and P-value, when doing Hypothesis Testing? Read this online: To find a rejection region, work backwards from the level of ...
### Chi-square test statistic is significant but $p$-value says otherwise - what's the correct interpretation?
I have obtained a Pearson's Chi-Square test statistic value of $0.065$, for $1$ df, and a $p$-value of $0.799$. Comparing my calculated $\chi^2$ test statistic with the critical value in the $\chi^2$...