All Questions

My independent variable has a huge proportion of zeros in the data, and I've been thinking of using a zero-inflated Poisson regression to account for this. However, this method is only specified for ...

I strongly feel that this question has been answered or explained somewhere, however, I'm struggling to find the correct terminology and resources to learn about this, and I believe this post may have ...

If weights are not shared the number of parameters will be extremely large and difficult to compute which I understand. I don't understand the argument that varying length inputs is taken care by ...

I have a second-order differential nonhomogeneous linear equations? And their solution $y(1)=c_1x^2+c*cosx$ $y(2)=c_2x^2-c_3x+c*cosx$ $y(3)=x^2-c_4x+c*cosx$ what is the set of fundamental solution ...

I am using a program in R to conduct the wildbootstrap Variance Ratio Test used by Mckinley and Lo(1988) in order to predict the underlying expectancy of the s&p 500. (To tell whether it's random, ...

Hello amazing community! I am attempting to run an ordinal regression (one ordinal (likert scale) DV) and multiple IV (categorical, nominal). I tried doing an ordinal regression in SPSS but ...

I wonder if there is a book talking about profile likelihood in detail, about the parameter computation procedure (grid search, newton-raphson method, or iterative estimation (converge or not?)); ...

A variation of this question has been asked, but certain items remain unanswered - I am modeling the proportion of mortality (Prop) using a single continuous predictor variable which is temperature (...

I am deciding between a panel regression with fixed effects or random effects. The outcome variable here is labor force participation rate "lfp_rate", and one independent variable is poverty ...

I was looking around for a good explanation as to why LSTMs are better able to handle vanishing and exploding gradients compared to vanilla RNNs. I know it is due to the cell memory $c_t$ acting as a ...

The question is about the 2nd data table from the article Symptom improvement in children with autism spectrum disorder following bumetanide administration is associated with decreased GABA/glutamate ...

In a paper by Mark P. Taylor he conducts ADF tests on exchange rates and he describes the determination of lag number with "The number of lagged dependents that we need to include to induce ...

I'm trying to model deforestation as a survival analysis. I have a raster map where unaffected areas are zero and deforested pixels have values 1-20 depending on the year of deforestation (2001-20). I ...

I'm looking to calculate the degrees of freedom (df) for a chi squared test which has one dependent group with 3 categories and one dependent group with 4 categories. What would the df be?

Say I have a table of data with four columns labelled A, B, C, D, where each entry is either a 0 or 1, how do I calculate P(D=1|A=1,B=1,C=1) from the data? Can I use P(D|A,B,C)=P(A,B,C,D)/P(A,B,C)? ...

Heteroskedasticity means that the variance of the residuals changes with respect to input variables. Is there a name for an analogous concept where the shape of the distribution, i.e., skewness, ...

I have a poisson distributed liklihood, and a gamma distributed prior. I know that the posterior distribution is also gamma because gamma is a conjugate prior of the poisson distribution. I multiplied ...

I tried to make a logistic regression classifier to predict the class of unseen data. In this data cross terms play important role to predict the multi imbalance class, with this information I cannot ...

Problem description Suppose we have fixed number of people that are the test population, let's say $t=200$ persons. For each one of them $\mathbf{r}_j$ we know about $m=300$ features that describes ...

I have data for neighbourhoods with median income. I also have a standard low-income cutoff. (Just using regression analysis) I feel it would lead to a simpler and cleaner result if I just use the ...

In rpart I estimated the complexity parameter to which it is convenient to prune the tree. I used the grid search and the functions of another package, ...

I'm new in time series analysis and I'm currently working with a time series that has a trend and a marked seasonalization. As a result, I've detrended and deseasonalized the series before plotting ...

Is it possible to infer the power from the distribution of a statistic? For instance, let's assume we are dealing with a Wald statistic of given mean and variance. Here is the distribution of this ...

What's the meaning of indexes in the definition of populational regression? $$Y_i=\beta_0+\beta_1X_i+e_i$$ When we have a sample the indexes make sense to me because we have each $x_i$ associate with ...

I have written the code in this gist that classifies poker images with a neural network. Training reaches 99% accuracy but when reloading the trained model, all is wrong. https://gist.github.com/...

The TL;DR of the dataset is this: The data set I'm working with is a set of votes. Experts in a field vote for outcome A or outcome B and I'm running a logistic regression to get a feel for how the ...

In a summary of this behavioral economics article, it says Our third finding is that cross-consumer heterogeneity in biases is poorly explained by even a “kitchen sink” of other consumer ...

I am looking for research articles on different research databases, such as google scholar, sciencedirect, web of science, etc. I was wondering, if there is a way to find research articles using a ...

Suppose I have $p$ students who take an exam with $t$ questions, and $r$ raters who will be involved in scoring these questions. For each student, $s < t$ questions were randomly assigned for ...

I am estimating a VAR-model with three (anual) variables: GDP, Unemployment rate and Inflation. (57 observations) Inflation and GDP are I(1), so I want to use them as growth rates in the model. But ...

If I have a regression model $Y = \beta_0 + \beta_1 A + \beta_2 B$, where $A$ and $B$ are treatment indicators. Firstly, if I frame the definition of $\beta_1$ in terms of expectations, how do you ...

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I'm currently estimating a DCC-type model by maximum likelihood. Im using the command solnp and it return an object where I can compute the Hessian H evaluated at ...

As I understand minimizing the sum-of-squares error function is equivalent to maximizing the likelihood function and in fact the sum-of-squares error function stems directly from the derivation of ...

I am confused with the the binary classifier evaluation criteria in anomaly detection domain for highly imbalanced data. I see that some authors claimed that their model performed excellent to predict ...

I have a set of data in histogram format with uneven bin sizes, which represents the weight of horses at a certain point in their lifetimes when they are switched from grazing to a racing diet. Here ...

I have to improve my panel data analysis by detecting outliers. I already tried by removing them manually. Do you know some function running robust fixed effect or random effect model? There is ...

I have 2 questions needed to be answered. Do I need to apply PCA only on the train dataset? And then test the performance of models on the original test data? Or shall I apply PCA on the whole data ...

I have been stuck trying to apply the function rescale() of the scales package to a data frame. The tricky thing is to apply this function by groups based on the "f.name" categorial factor ...

I have built a weighted least squares regression model and was about to interpret the results. But before doing that, I wanted to check for assumptions first. However, I couldn't find the assumptions ...

I have a large water chemistry dataset where my response variable (radium-226 concentration) has two types of missing data. Sometimes it is left censored, sometimes the value is reported, but most ...

We know that $Y$ is independent of a vector $X$ means it's independent of all linear combinations of components of $X$. Then I'm curious about the correctness of the following statement: If $Y$ is ...

I am working on a two-class classification task that involves the classification of samples from 10 subjects who belong to two different classes. The three main variables are: X - feature matrix (...

I have two groups of data (N > 30 in each group). I want to know if the two groups differ from each other. So I thought about making an independent t-test. But then I remembered that the groups ...

I have read that in regression there is no need for the response variable (independent variable) to be statistically independent. The source is https://en.wikipedia.org/wiki/...

What, if any, asymptotic arguments are used in moving between the various statements of the central limit theorem (e.g. in terms of sample means compared with standardised sample means)? Context. My ...

In class, our professor explained that the martingale process is the in between case of random walk type I (innovations are i.i.d.) and random walk type II (innovations are serially uncorrelated). ...

In my econometrics lecture we discussed the consistency of the OLS estimator ($\hat{\beta} \overset{P}{\rightarrow}\beta)$ and I don't understand why it holds that $(X'X)^{-1}=\Big(\frac{X'X}{N}\Big)^{...

Que ) what is the Logistic Curve ? Describe in detail method of Pearl and read and also rhode's method of fitting a Logistic Curve to population data. Now in this question I know the first part of ...

i run a Tukey HSD test insade the r package agricolae and got significant diffenrences between my groups. Now I would like to report that in a figure with the basic significance asteriks. How can I ...