Questions tagged [nonparametric]
Use this tag to ask about the nature of nonparametric or parametric methods, or the difference between the two. Nonparametric methods generally rely on few assumptions about the underlying distributions, whereas parametric methods make assumptions that allow data to be described by a small number of parameters.
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How to explain such a big difference between parametric and non parametric test (and other questions)?
I am advising a small medical study (two groups, treatment is a dummy variable), i.e. a 2x2 contingency table. I'm comparing the value of the Pearson's $\chi^2$ test and a non parametric competitor ...
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What software allows non-parametric repeated-measures multi-way Anova? [duplicate]
A previous user asked this question specifically for R. I'd like to know what, if any, other software can do this.
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How to test group differences on a five point variable?
I have a series of observations that fall into bins (or "scores"); that is, the data can be 0, 1, 2, 3 or 4. There are two groups of such data, control and treated. I know the number of individuals ...
John
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Wald-Wolfowitz Runs Test for Normality Assumptions Testing
Some guys told me that it's appropriate to use Wald-Wolfowitz Runs Test as a normality test (like Shapiro-Wilk's or Kolmogorov-Smirnov...). Do you think this is good way to test normality assumptions?
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Density estimation methods?
What non-/semiparametric methods to estimate a probability density from a data sample are you using ?
(Please do not include more than one method per answer)
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Whither bootstrapping - can someone provide a simple explanation to get me started?
Despite several attempts at reading about bootstrapping, I seem to always hit a brick wall. I wonder if anyone can give a reasonably non-technical definition of bootstrapping?
I know it is not ...
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What is the weak side of decision trees?
Decision trees seems to be a very understandable machine learning method.
Once created it can be easily inspected by a human which is a great advantage in some applications.
What are the practical ...
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How can I obtain some of all possible combinations in R?
Sometimes I want to do an exact test by examining all possible combinations of the data to build an empirical distribution against which I can test my observed differences between means. To find the ...
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A non-parametric repeated-measures multi-way Anova in R?
The following question is one of those holy grails for me for some time now, I hope someone might be able to offer a good advice.
I wish to perform a non-parametric repeated measures multiway anova ...
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Why haven't robust (and resistant) statistics replaced classical techniques?
When solving business problems using data, it's common that at least one key assumption that under-pins classical statistics is invalid. Most of the time, no one bothers to check those assumptions so ...
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Help me understand nMDS algorithm
I have been reading Zuur, Ieno and Smith (2007) Analyzing ecological data, and on page 262, they try to explain how nMDS (non-metric multidimensional scaling) algorithm works. As my background is in ...
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Robust nonparametric estimation of hazard/survival functions based on low count data
We're trying to use a Gaussian process to model h(t) -- the hazard function -- for a very small initial population, and then fit that using the available data. While this gives us nice plots for ...
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