Linked Questions
11 questions linked to/from t-test when the data population is not normally distributed
77
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15
answers
13k
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Why would parametric statistics ever be preferred over nonparametric?
Can someone explain to me why would anyone choose a parametric over a nonparametric statistical method for hypothesis testing or regression analysis?
In my mind, it's like going for rafting and ...
- 957
5
votes
3
answers
1k
views
How do I compare the results between two different Likert Scales questionnaires?
For my dissertation, I am currently evaluating pharmacy students' perception on two distinct academic electronic health record systems - A and B. The students were asked to identify how much they ...
- 59
5
votes
3
answers
750
views
Should the t-statistic (not data) be normally distributed for using the t-test?
Reading the introduction of English Wikipedia's article about the t-test, I was confused by this statement:
It is most commonly applied when the test statistic would follow a
normal distribution
To ...
- 53
3
votes
3
answers
2k
views
importance of CLT in t-test and z-test
I was going through the assumptions of z-test and t-test, all most all of the references mention that the data should be normally distributed. There is no mention of estimator's distribution. If the ...
- 97
3
votes
2
answers
502
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How to use one-sample t-test on skewed distributions?
I have been reading that people use the one-sample t-test also for skewed underlying distributions, saying that for a high enough number of datapoints (I read for example N=30 and N=100 in some places)...
- 31
0
votes
2
answers
1k
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p-value test for comparing classifiers
I have to use p-value test to compare two classifiers. I am getting the error vectors of 2 hypothesis and I am using their difference as an input in ttest function of MATLAB
...
- 101
0
votes
0
answers
538
views
How do I test differences between two (non-normal) distributions?
I have a large dataset containing the peak velocities of different people. I have then split this dataset into two depending on an attribute (for example male vs. female). Each dataset now contains ...
2
votes
0
answers
151
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Which distributions are valid for Student's t-test?
When I read Wikipedia - Student's t-test I can see it assumes that:
The sample mean follows a Gaussian distribution.
The sampled mean follows a chi square distribution.
Samples of Gaussian ...
- 277
2
votes
1
answer
61
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Can you help me determine if these two groups are statistically different?
I have two groups, A & B. Let's say A are the users who wrote a review for place A, and B for place B.
For each user $u$ I have recorded his total number of reviews $r_u$. Since we're talking ...
- 566
0
votes
1
answer
34
views
How to model individual estimates of probabilities
I have data from human participants who had to estimate the probability of an event happening under conditions A and B. They used a slider on an interval of 0-1 where 0 means the event is not gonna ...
- 137
0
votes
0
answers
35
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In a skewed sample with a large n, does Central Limit Theorem dictate that a t-test can be used, even if the mean cannot be interpreted? [duplicate]
I understand that, in the case of a highly skewed population and sample, the sampling distribution of the mean can still be normally distributed if the sample size is large, according to Central Limit ...
- 95