68k views

### t test with drastically different sample sizes [duplicate]

I'm investigating if two of our processes are producing products with the same or different average measurements. The first process has been used for a very long time and thus I have a sample size ...
6k views

### What method is preferred, a bootstrapping test or a nonparametric rank-based test?

I want to perform a single-tail test on a single sample of real numbers (N~100) against an expected value. The population is known to be not normally distributed. So from what I've read about stats, I ...
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3k views

### Two methods of using bootstraping to test the difference between two sample means

I'd like to bootstrap test a hypothesis (two sample Student's t-test). In Efron and Tibshirani 1993 p.224 there is explicit code for that: for each observation, subtract its group mean and add the ...
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### converting a bootstrap confidence interval into a p-value

If a bootstrap confidence interval (CI) can be interpreted as a standard CI (e.g., the range of null hypothesis values that cannot be rejected) [also stated in this post]. Is it ok to derive a p-value ...
• 1,694
2k views

### How to test right-skewed distribution hypothesis?

Statistics is new to me. My dataset has 7000 incidents that were processed within x number of days. I took a sample of 400 from the population: ...
2k views

### R : Calculate a P-value of a random distribution [duplicate]

I want to get the P-value of two randomly distributed observations x and y, for example : ...
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1 vote
839 views

### Very small sample compared to comparatively very large baseline

I would like to know if a small test group (~5 samples) is significantly different from baseline (300-400 samples). I initially considered Student's T-Test, but it seems that I wouldn't be able to ...
• 43
99 views

### Confidence interval for the ratio

I have a problem that each customer gives us a revenue and a cost, one of the indicators of the company is the: $\frac{\sum Costs}{\sum Revenue}$ To estimate the confidence interval for this parameter ...
91 views

### Using non-parametric bootstrap to assess relative difference between means of two samples

Let's say we have 2 samples, A and B. I'd like to find out which distribution has a higher mean by using non-parametric bootstrap. My procedure goes like this: Calculate the mean of a resample 1 from ...
• 207
1 vote
126 views

### Using bootstrap to compare performance of two machine learning models

I have a binary classification problem, and two ML models $A$ and $B$. I evaluate performance of these models using the area under the ROC curve (AUROC). I want to assess whether model $A$ is ...
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1 vote