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.
2,126
questions
1
vote
0
answers
32
views
Strong consistency of kernel density estimator
I am studying the book Nonparametric and Semiparametric Models written by Wolfgang Hardle and have difficulty with the following exercise:
$\textbf{Exercise 3.13}$ Show that $\hat{f_h}^{(n)}(x) \...
- 111
2
votes
2
answers
370
views
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 $\mu, \sigma^2$ ...
- 235
0
votes
0
answers
103
views
How to construct homogeneous subsets table for nonparametric tests?
Does post-hoc for friedman tests or nonparametric testshave like a homogeneous subset table from SPSS? Mean doesn't represent it well so I tried using median but my data was zero-inflated so the most ...
- 295
1
vote
2
answers
163
views
Parametric vs Non-parametric test recommendation
What type of non-parametric test would be suitable for the dataset shown in the image:
The sample size is 200 each for both variables. The data value can vary from 0-4 for both variables. The ...
- 13
0
votes
0
answers
18
views
Is there a method bias when I prefer a specific post-hoc that shows a significance after significance in test of difference in groups?
I'm working to see if a machine does better than a worker in terms measurement (by having a measurement from an expert be the control). So my dataframe contains the Measurement Value, Measuring Device,...
- 295
1
vote
0
answers
43
views
Why is histogram density estimation nonparametric?
My understanding of histogram density estimation:
For $k$ predefined equal-width bins $(b_0, b_1], (b_1, b_2], ..., (b_{k-1}, b_k]$ and $n$ observations $x_1,...,x_n \in (b_0,b_k]$, we estimate ...
- 11
3
votes
1
answer
695
views
I have applied many statistical tests to my data, but still cannot determine normality
I have run multiple tests to determine normality on my dataset, but I am unsure which one to adhere to, especially since my histograms, density plots, and QQ plots leave much to be desired in terms of ...
- 53
0
votes
0
answers
64
views
Multivariate analysis for non-normal variables
Edit: I am trying to produce a model in R in order to analyze the relationship between several variables. I am looking at the relationship between behaviour and dispersal of a population. Each ...
3
votes
1
answer
131
views
If I have a very small n for one group and a very large number of features, should I choose a parametric or a non-parametric test?
I have a dataset that contains human metabolite concetration in a fluid. One group has about 12 samples, while another only has 5. My question is if I can assume normality for this data and do ANOVA/t-...
2
votes
1
answer
152
views
Covariance between two binomial random variables or expectation of product of binomial random variables
I have an empirical distribution $S_n(x)$ (= proportion of samples less than equal to x) from a random sample $X_1, X_2, ..., X_n$ for a random variable $X \sim F_X$. Consider the random variable $T_n(...
- 61
0
votes
0
answers
21
views
GLMM not working if I specify the distribution as gamma
Following is the histogram and Q-Q plot of deceleration data retrieved from driving simulator experiment. As the data is not normally distributed, I am using generalized linear mixed model to analyze ...
- 1
0
votes
1
answer
56
views
Non-Parametric Test for Regression Significance
I have created a plot of the regression slope of sea surface temperatures (x) and an atmospheric variable (y). Although, I need to test the statistical significance of these trends using a non-...
1
vote
1
answer
45
views
Comparing data with opposite distributions
What test can I use to compare whether the difference between the following sets of data are significant.
I know, I can just look at them, but I'd like it to be a bit more scientific than that. The ...
0
votes
0
answers
71
views
How to determine significance for a Corrado rank test in an event study?
I apologise if this is a stupid question (it feels stupid tbh). I am currently doing an event study and my abnormal returns are not normally distributed. I am now in the process of performing a ...
0
votes
0
answers
17
views
Mixture of Conditional Random Variables by Sampling
I am struggling to put my transformation of data into mathematical contexts. My goal is to define a mapping that transforms the original data into some awkwardly mixed data. In my simulation study, I ...
- 1
3
votes
1
answer
88
views
Is this nonparametric tests with the same data valid?
I have 6 algorithms, and each algorithm I use on N problem instances (say N is around 200).
I divided the algos into two groups, 3 into group A and 3 into group B. They are divided into two groups ...
- 33
0
votes
0
answers
33
views
Understanding the bootstrapped method for calculating non-parametric p-values
I'm trying to understand the non-parametric bootstrapping to calculate p-values. I understand pearson correlation has it's own method for calculating p-values but I'm just using this as an example.
...
- 1,472
0
votes
0
answers
31
views
Anova violates normality assumption for error data
I have a 2 x 2 repeated measures ANOVA (N = 51) with Error Rate data as the dependent measure. The error data violates the normality assumption, even when outliers are removed. I have looked at the ...
- 113
1
vote
0
answers
43
views
Alternative to Bonferroni Correction for Dichotomous Variable? [closed]
I am working with a dichotomous variable and my supervisor has asked me to apply a Bonferroni correction to our data using SPSS. From my understanding, Bonferroni corrections are used when performing ...
- 97
1
vote
0
answers
23
views
Appropriate tests and normalization approaches for highly non-normal data
I'm trying to ascertain whether a particular type of article, $T$, is associated with higher engagement scores in academic journals, and how substantial the effect size might be. I have raw data of ...
- 323
2
votes
2
answers
164
views
Multiple regression on unpaired data (A~B+C)
I am not sure how to test one of my hypothesis from my data.
Basically, I have 3 behavioral measures A, B and C, and I want to test that A is a composite of B and C: A = B+C
However, for practical ...
- 21
1
vote
1
answer
111
views
OLR for non-normal continuous dependent variable with two categorical independent variables?
ID
Sex
Surface
B1
1
female
UN
1255
2
female
UN
542
3
female
UN
818
1
female
UN
274
2
female
UN
261
3
female
UN
314
1
female
UP
552
2
female
UP
548
3
female
UP
721
1
female
UP
431
2
female
...
- 11
1
vote
0
answers
171
views
Projection pursuit regression
Projection pursuit regression (PPR) is described in Hastie et al.'s The Elements of Statistical Learning in the chapter on neural networks. The algorithm was introduced by Friedman and Stuetzle (1981)....
- 751
2
votes
2
answers
121
views
How do I compare my data with the general population data in SPSS
My purpose is to compare my data with the general population data derived from a published report. I can only extract mean, median, 5th, 95th and 97.5th percentiles from it. Also, My data is non-...
- 21
2
votes
1
answer
177
views
Can ANOVA suffice for comparing mean of percent/proportion data?
I've been handed off some data to analyze and I'm looking for something simple and straightforward. The 1 response variable/dependent variable is average percent mortality from 7 treatment groups (...
- 101
3
votes
1
answer
55
views
Bonferroni correction gives weird results in R
I have this dataset:
Treatment
data
T1
0
T1
0
T1
0
T10
0
T10
0
T10
0
T11
0.2
T11
0.2
T11
0.2
T12
0
T12
0
T12
0
T2
0.7
T2
0.6
T2
0.6
T3
0.8
T3
0.7
T3
0.8
T4
0.3
T4
0.3
T4
0.4
T5
...
- 53
1
vote
0
answers
24
views
Gaussian white noise model in application
I am interested in applications (to data) of non-parametric statistics, and my question concerned the Gaussian white noise model defined by,
$$
X_{t_1, \ldots, t_d}=f\left(t_1, \ldots, t_d\right) d ...
- 11
1
vote
1
answer
236
views
In an A/B test, how can you check if assignment to the various buckets was truly random?
Trying to figure out how I can confirm that my A/B Test assignment is truly random. I know the runs test is used to test for randomness.
Is it possible to use the runs test to check if my A/B Test ...
- 65
1
vote
2
answers
2k
views
Non-parametric test for comparing means of 2 or more dependent variables in R?
I have a matched paired dataset (student survey before a topic was taught and student survey after the same topic was taught) where I compare the means of their answers (answers are given in Likert ...
denise
3
votes
1
answer
218
views
What exactly does the “symmetric distribution” assumption of the Wilcoxon signed-rank test refer to? [duplicate]
I have two lists (or sets) of data that I would like to statistically compare. More precisely, I would like to check if the difference between data list one and data list two is statistically ...
- 307