# All Questions

138,955 questions
5 views

### Test to compare means of non independent samples with repeated measures

I am struggling a little to know if I am comparing independent or not independent data and I am not sure what kind of test I should use. Here is the pitch : I would like to compare latencies between ...
7 views

### How to calculate the mean over uneven observation times?

Possibly a very basic question, but I would really appreciate clarification from those with a strong background in stats/epi. I have a number of human patient medical records. They are retrospective ...
7 views

### Extreme Value Simulation from Copulas with Monte Carlo

I'm trying to simulate the tail values from a multivariate distribution using copulas. I'm using Vine Copula package of R to derive the suitable copula for my data and I generate random samples out of ...
4 views

### Mediation, All significant but negative total effect, positive direct effect, negative indirect effect - Help!

I am doing a mediation analysis using PROCESS, and need some help with the below: Total effect of X on Y ...
3 views

### Statistical analysis of multiple trials (3 categories) at 3 time periods for 2 group of subjects

I am confused about statistical analysis of an experiment in which there are two groups of subjects i.e. experimental & control. Each group goes through a treatment and multiple readings of ...
8 views

### Increasing number of observations worsen the regression model [on hold]

I have this code ...
10 views

### Question related to poisson process [on hold]

Customers arrive at a bank at a Poisson rate of λ. Let M(t) be the number of customers who enter the bank by time t only to make deposits to their accounts. Suppose that, independent of other ...
4 views

6 views

### GMM estimator: Two-step vs. Iterated estimator

I'm currently trying to understand the differences between the two-step efficient GMM estimator, and the Iterated GMM estimator. As I understand the T-S, is based on the First-step and depends on the ...
Problem In order to find the optimal parameter $\lambda$, each individual observation is taken out from design matrix $\mathbf{X}$ and solves  \text{minimize}_{\beta} \frac{1}{2}\Vert \mathbf{y}_{-...