All Questions
Tagged with simulation regression
120
questions
1
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0
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57
views
Least-bad stepwise procedure for a simulation that shows issues with stepwise regression
I am well-aware of the issues that stepwise regression causes. I want to demonstrate some of them via simulation in a particular situation.
I am thinking of a regression where I have some categorical ...
- 65k
3
votes
1
answer
47
views
How to simulate non-standardized artificial data for logistic regression?
I would like to simulate data for a logistic regression with the predictor variables on their original scale.
There are, of course, a litany of similar previous questions (e.g., here, here, and here). ...
- 133
3
votes
1
answer
129
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Gaussian noise added in social sciences data
In a simulation study (number of simulation $n=200$), there is this quadratic/parabolic function simulated with Gaussian noise added:
...
- 953
3
votes
1
answer
574
views
Calculating minimum sample size required for repeated measures linear mixed model using the simr package
I would like to use the simr package to calculate the smallest sample size needed to achieve $0.80$ power at the $0.05$ alpha level while accounting for a small ...
- 31
2
votes
1
answer
52
views
Omitted variable bias: 3 correlated variables and 1 omitted (R simulation)
I get weird results when trying to analyze omitted variable bias in R.
If I try to analyze the bias for coefficient $\beta_j$ of variable $x_j$ in case of one omitted variable from set of two ...
- 205
0
votes
0
answers
25
views
Analyzing multiple data points per condition of a simulation model
I wish to perform statistical analysis on a data set that is the result of running a simulation model.
I have simulated this model by varying five parameters, TA_PS, TA_IP, PA_PS, PA_IP, and PA_LGPP. ...
- 13
8
votes
1
answer
526
views
Power analysis for GAMM
Question
I am struggling with understanding how to run a simulated power analysis for GAMMs. Though my planned studies will include more variables, the core issue I'm trying to work out is to simulate ...
- 15.9k
2
votes
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34
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What's the theoretical basis of sampling ols regression coefficients from a multivariate $t$-distribution instead of a multivariate normal?
In their 2000 paper "Making the Most of Statistical Analyses: Improving Interpretation and Presentation", Gary King et al. present a method of using simulation to compute quantities of ...
- 31k
1
vote
1
answer
23
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Regression Simulation with random variable - Getting pvalue
i have the following problem:
I have a sample of individuals who have opinions on certain subjects. I have to group these individuals randomly in groups the same size for every subject and take the ...
- 11
1
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0
answers
55
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Understanding and simulating a classic linear regression model with fixed coefficients
I had used the GPT chat to ask some straightforward questions. However, one of the responses left me feeling quite confused. Currently, I am studying the classical regression model given by
$$y_t = ...
- 247
4
votes
1
answer
111
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How to simulate variability (errors) in fitting a gamma model to survival data by using a generalized minimum extreme value distribution in R?
As shown below and per the R code at the bottom, I plot a base survival curve for the lung dataset from the survival package ...
- 857
3
votes
1
answer
119
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In regression, should we adjust for variables only associated with the independent or dependent variable?
I have recently been reading more about causal inference so am trying to conceptually think about model specification in more detail. From reading (e.g. this paper), we adjust for confounders which, ...
- 133
3
votes
1
answer
95
views
Generating a bootstrap simulation of the response in regression
I'm studying regression bootstrap procedures for my thesis, and have stumbled something which I find difficult to understand. Consider the standard normal linear model
$$
Y = \beta x + \epsilon \,, \...
1
vote
0
answers
36
views
Probablistic linear regression predictions for simulation tasks
I have a linear regression task where I am trying to predict in the interval of roughly [-100, 100]. I'd like to build a GBM (it doesn't have to be) that allows me to see the probability distribution ...
- 226
8
votes
1
answer
839
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How to simulate data for an interaction?
I'd like to simulate data for an interaction / moderation with a continuous exposure and outcome and binary moderator. For example, for the association between X and Y to be 0.1 when moderator = 0 and ...
- 471