All Questions
37
questions
0
votes
0
answers
51
views
Why the MSE of the fitted data is not equal to the sum of the bias and the variance in R?
I use simple linear regression and I want to find the decomposition of MSE, that is as a sum of the bias, the variance and the variance of the error terms. I have the following code:
...
0
votes
1
answer
70
views
How to compare two multivariate distribution (of distances) to zero in terms of mean and variance in R?
We have N 3D coordinates estimated with two methods and want to compare them with a reference set of N 3D coordinates which is the ground truth, so in notations:
...
- 303
2
votes
1
answer
270
views
mlogit + logitr packages fail to recover true estimates of mixed logit random coefficient model
I am running Monte-Carlo simulations on a simple DGP of a mixed logit random coefficient model to check if the mlogit and logitr ...
- 21
1
vote
0
answers
16
views
How to detect bias between two experiments
I need to analyse one dataset composed of two experiments. The goal is to identify sick individuals (animals) based on different parameters. These parameters have been collected on different farms (...
- 41
1
vote
1
answer
34
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Why is standard error of clustered observations not under-estimated?
I regularly read that clustering will cause standard errors to under-estimated. So I simulated two distributions - one with clustered observations, one without. In both cases the standard error is 0....
- 14.5k
4
votes
1
answer
209
views
How to deal with sampling effort bias in biostatistics?
I am working on a dataset composed of different sites, where several replications were carried out on each site to measure abundance and biomass of observed species. Each site has its own level of ...
- 87
0
votes
0
answers
36
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How to correct sampling effort bias? [duplicate]
I am working on a dataset based on different sites, where each site has several transects. However, the sampling effort is not the same for each site (8th or 6th order sampling strength), which poses ...
- 87
4
votes
2
answers
9k
views
Calculating Bias in R
Write a simulation experiment to estimate the bias of the estimator λˆ= 1/ X¯ by sampling using x=rexp(n,rate=5) and recording the values of 1/mean(x). You should find that the bias is λ/n−1. Here we’...
- 41
1
vote
1
answer
99
views
poisson regression for events in a slice of time for a cohort (rather than in a designated start and stop time)
I am interested in determining if the different version of my favorite gene a patient has affects the number of prescription they fill for opiods.
I think I can do this with poisson regression. My ...
- 115
3
votes
1
answer
3k
views
Regression to the mean and its formula in R
In this book, the estimate of the regression to the mean phenomenon is said to be: $Prm=100(1-r)$.
Where $Prm$ is the percent of regression to the mean, and $r$ is the correlation between the two ...
- 4,076
1
vote
0
answers
82
views
Conjoint analysis: bias due to no-choice option and linear attribute
At the moment I am analysing survey data using Bayesian estimation in R (bayesm package)
For my analysis, I have included a no-choice option that is coded as a series of zeros. However, I also have a ...
- 11
0
votes
0
answers
756
views
Fixed and Proportional bias
I have a question regarding the fixed and proportional bias.
The definition for Fixed bias is:
Fixed bias is present if the confidence interval for the intercept of the OLP regression line DOES NOT ...
0
votes
1
answer
859
views
Positive model bias but negative percent bias; why?
I'm comparing my training data with some predicted values using the Metrics package in R. When running the bias function, R ...
- 127
1
vote
0
answers
22
views
Duration Biases in Survival Analysis
I'm doing a simple Kaplan-Meier Survival analysis, but my survival times, especially my median, is longer than it should be, leading me to believe there is a duration bias. I have person-level data, ...
- 11
2
votes
0
answers
112
views
Controlling the allocation bias in small RCT
In order to contain the allocation bias, I would like to understand if it is possible to have a randomization process during the patients enrollement controlling ...
- 342