Questions tagged [parametric]
The parametric tag has no usage guidance.
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How to fit data to a parametric curve/model (x(t), y(t)?
I've got data of x and y pairs and I'd like to fit it to a model that is parametrized as f = (x(t), y(t)). Unfortunately, there is no way for me to analytically solve for t and get a direct ...
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I want to show by simulation that the Wilcoxon test is more robust than the Student test for non-normally distributed data
I want to test by simulation that the Wilcoxon test is more robust than the Student test for non-normally distributed data.
For example, I'm testing the ...
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Interpreting AFT Model Coefficients: Mean vs. Median Survival Time in Log-Normal Distribution
When interpreting the coefficients of an Accelerated Failure Time (AFT) model that assumes a log-normal distribution, should we focus on the impact of coefficients on the mean survival time or the ...
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Parametric copulas with marginals that are regressions
In Dependence Modeling with Copulas (Harry Joe) I'm struggling to interpret the meaning of a statement. In Chaper 5.1, it is stated:
Parametric inference for copulas
For dependence modeling with ...
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Which statistical test is appropriate to compare two parametric bootstrap samples drawn from model fits of two time series?
In previous threads , parametric bootstrapping was suggested as a method to test for differences between time series at specific time points. I have followed the methods as described in this answer (...
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Can multicollinearity of parametric terms in a GAM be ignored?
I've had such a hard time finding a source that addresses how to handle multicollinearity of parametric terms in a generalized additive model (GAM) that I'm starting to think it may not be important, ...
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Parametric or non parametric mixed effect models for very small sample size in ecological/soil data?
I am running an ecological/environmental experiment in a salt marsh with 5 experimental treatments and 3 replicate soil samples taken from each treatment. I have been taking measurements from these ...
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Estimators that are superefficient on a dense set
In Chapter 8 of van der Vaart's Asymptotic Statistics, it is shown that (under weak regularity conditions) an estimator can be "superefficient" on at most a set of Lebesgue measure zero (...
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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 ...
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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-...
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Must an alpha=0.01 be used to interpret significance of parametric terms in a GAM?
I have fit a time-series count HGAM with environmental covariates as parametric terms and year as a site-varying smooth term. I am wondering if I need to use an alpha threshold of 0.01 to interpret ...
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GAM - parametric coefficients - what is mgcViz::pterm() actually plotting?
I built a GAM with two categorical variables and two smooth terms, following this structure:
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Is there a statistical test for five groups with averages ONLY?
The data I collected was measuring plant shoot masses and these were extremely small, so I could only find the total mass of the shoots from 30 plants. Hence, I only have the mean and none of the ...
user387381
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Fisher Z transformation still not normal
I have 18 different groups that I need to compare. I used the raw values from a neuroimaging file to represent synchronization between two brain regions (which ranged from 0 to 1) and Fisher Z ...
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How to interpret the partial effect plots for parametric terms while using gratia::draw() and gratia::parametric_effects()?
I am asking a question akin to this one: https://stackoverflow.com/questions/71884457/what-does-the-y-axis-effect-mean-after-using-gratiadraw-for-a-gam but am wondering the same question for ...
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