Linked Questions

1
vote
0answers
400 views

Why according to distribution graph it's normally distributed, but Jarque-Bera test shows non-normally distributed? [duplicate]

I am working on Kaggle's house pricing exercise and I cannot understand something. I watch and read articles on normality tests, and more specifically JB test, but I cannot understand why according to ...
344
votes
16answers
121k views

Is normality testing 'essentially useless'?

A former colleague once argued to me as follows: We usually apply normality tests to the results of processes that, under the null, generate random variables that are only asymptotically or ...
13
votes
11answers
7k views

Is a distribution that is normal, but highly skewed, considered Gaussian?

I have this question: What do you think the distribution of time spent per day on YouTube looks like? My answer is that it is probably normally distributed and highly left skewed. I expect there is ...
38
votes
6answers
10k views

How did scientists figure out the shape of the normal distribution probability density function?

This is probably an amateur question, but I am interested in how did the scientists come up with the shape of the normal distribution probability density function? Basically what bugs me is that for ...
35
votes
4answers
68k views

How is Poisson distribution different to normal distribution?

I have generated a vector which has a Poisson distribution, as follows: x = rpois(1000,10) If I make a histogram using hist(x)...
14
votes
11answers
7k views

Is standard deviation totally wrong? How can you calculate std for heights, counts and etc (positive numbers)?

Let's say I am calculating heights (in cm) and the numbers must be higher than zero. Here is the sample list: ...
26
votes
4answers
13k views

Is Shapiro–Wilk the best normality test? Why might it be better than other tests like Anderson-Darling?

I have read somewhere in the literature that the Shapiro–Wilk test is considered to be the best normality test because for a given significance level, $\alpha$, the probability of rejecting the null ...
4
votes
3answers
3k views

Are all continuous random variables normally distributed?

All the time I see examples of the normal/Gaussian distribution with continuous random variables. So my question is do all continuous random variables have a Gaussian distribution?
1
vote
0answers
108 views

Assessing Multiple Regression Normality

Normal distribution in data is one of the assumptions in multiple regression analysis. In the situation where the Skewness test, Kurtosis and Q-Q plot showed the evidence of normally distributed data,...
1
vote
2answers
44 views

Is there any particular historic/socio-economic reason why the distribution of car ages at an auction site follows a bell curve?

Just analyzed the image names of automobiles in an auto auction sale archive and filtered the image names by the automobile's model year and counted the years' frequencies. I came up with the ...