All Questions
10 questions
5
votes
2
answers
109
views
How to calculate the reference level interaction in regression in R?
I am very confused on calculating the reference level interaction in regression in R.
Here is the sample code:
...
- 364
3
votes
2
answers
1k
views
Which groups are reference groups in a regression model with interaction?
What are the reference groups in a regression model where there are interaction categories? Using the iris dataset in R, I've created a category with three levels ...
- 615
0
votes
1
answer
68
views
Are these effects missing from my glm output because of a possible dummy trap?
I have a few generalized linear mixed model questions. I have an experiment that asked "is there a differential response between asexuals and sexuals by population density?". I am ...
- 55
1
vote
1
answer
2k
views
Interaction effects in regression models - should I include reference category?
I have a question about coding interaction effects using dummy coding which I’d be really grateful for your advice on please.
Imagine I want to design an experiment to measure the impact of amount of ...
- 11
3
votes
1
answer
909
views
Interpreting the effects of dummy interactions
Warning
This question is quite long, and maybe a lot of you will think it is too long. I however thought, and hope, that if this question gets a proper answer, it will actually be a really good post ...
- 528
1
vote
0
answers
368
views
Panel Data Regression in R with Dummy Variables [closed]
I am currently working on my thesis and thereby analyzing the effects of the increase of COVID-19 cases on the main stock indices of the G7 countries. For this purpose, I have divided the whole period ...
- 11
0
votes
0
answers
33
views
Assess impact on results of participants recruited via additional outreach efforts
I am currently working on a project that evaluates certain study recruitment strategies in regards of increasing participation among different subgroups.
One of those strategies is reminder letters. ...
- 71
0
votes
1
answer
2k
views
Interaction term with several levels in multi linear regression in R [closed]
first of all thank you very much for admitting me!
I am currently stuck with a problem regarding interaction terms:
I would like to interact a categorical variable with several levels with a ...
- 25
2
votes
1
answer
2k
views
Simple effects of categorical interaction
I have two two-level categorical variables, IV1 and IV2. I want to fit a linear model in R and find out the simple effect of IV1 on the DV at each level of IV2, separately. I'm not interested in the ...
- 205
4
votes
2
answers
183
views
Variable for logistic regression is categorical and continuous so creates “missingness” in R
I am doing a logistic regression analysis using the glm command in R. It is to identify causes of valve narrowing beyond a certain threshold; 0=no narrowing, 1=narrowed. One of my variables is the ...
- 41