All Questions
Tagged with nonparametric normality-assumption
9
questions
7
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answers
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Is the inference from a parametric test valid when the population distribution is not normal?
This question arose from reading this post: T-test for non normal when N>50?
In the response to this post, the author outlines really well that the assumption of normality with regard to the t-...
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6
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2
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Can we ALWAYS assume normal distribution if n >30?
I'm in a debate with a coworker and I'm starting to wonder if I'm wrong but the internet is confusing me more.
We have continuous data $[0, \infty)$ that is retrospectively selected on individuals. ...
- 185
6
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2
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Wilcoxon Test - non normality, non equal variances, sample size not the same
I know there are already a lot of posts out there, but I couldn't find this exact combination in any of them.
Comparing two samples (Prices associated with men and with women), but I have neither the ...
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7
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2
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Non-Parametric altervative to one sample t-test
I have a the following hypothesis: $H_0: \mu=4$, $H_1: \mu\neq 4$, which I wanted to test using a one sample t-test.
However, my data is not normally distributed and a transformation was not found. ...
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4
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3
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Normality assumption and sample size
I know this is a very debated topic, even on this site, but I still couldn't find an answer to my problem.
Recently I am working with large samples (300, 400 and more). For now, I am trying to use ...
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1
vote
1
answer
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Transforming positively skewed data with positive and negative values
My data (see image below) is positively skewed and contains both positive and negative values. I'd like to transform it to achieve normality so I can apply a repeated measures ANOVA, but can't find a ...
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3
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1
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Two-Way Non-Parametric Test for Non-normal Data?
I have an unbalanced design with two factors, gender and site. I'm trying to test for differences in a size variable. Levene's test reveals that the data has equal variances. However, log transformed ...
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2
votes
2
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370
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How could Lilliefors use Monte Carlo if the estimand is not distribution-free?
Lilliefors test is a well-known statistical test for normality. Its idea is based on the Kolmogorov-Smirnov test, except the CDF is replaced by the CDF of the normal distribution with $\mu, \sigma^2$ ...
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what is the meaning of 'normality' as a difference between parametric and nonparametric method? [duplicate]
I'm so confused of the definition of the terminology, "normality". I mean, normality of what?
According to central limit theorem, regardless of the distribution of population,the computed values of ...
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