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1answer
65 views

How to explain control variables and interaction effects

I'm a bit stuck on running a GLM between 3 continuous variables in R. I can't make them categorical as it removes the significance. I have two questions. I'm analysing data on eggs. I had read that ...
2
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2answers
29 views

Balancing gender in an experiment

Say a study aims to see if two variables A and B are correlated in the general population. It isn't clear to me how extraneous variables like gender should be treated when the sample is selected. Each ...
1
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0answers
34 views

How to assess whether IQ predicts emotional experiment more at time 1 or time 2 controlling for covariates?

I have the following data set of a two-wave longitudinal study in educational psychology. A group of 400 people did some questionnaire on IQ, personality and two different emotional states (sadness ...
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0answers
14 views

Controlling for respondents' propensity to rate high/low or moderate/extreme

I am doing a simple linear regression to test the relationship between voters' self-reported policy stands and their approval ratings for two hypothetical presidential candidates in a simulated ...
1
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2answers
103 views

How to determine the correlation between 2 time series while controlling for a 3rd?

I would like to determine the relationship between two variables after controlling for a third. Specifically, I want to know if the prices of mercury and gold over time are correlated with each other ...
14
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3answers
781 views

What does “all else equal” mean in multiple regression?

When we do multiple regressions and say we are looking at the average change in the $y$ variable for a change in an $x$ variable, holding all other variables constant, what values are we holding the ...
4
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2answers
62 views

How can I calculate the effect of my equipment on my sport's performance?

I'm doing a stationary sport like golf, so the details matter. I'm recording each of my scores with detailed information about the equipment I'm using, and the weather conditions. So 1 score has 2-3 ...
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2answers
147 views

How are partial regression slopes calculated in multiple regression?

I'm trying to understand how multiple regression statistically controls for the effects of other predictor variables when calculating partial regression slopes. In a multiple regression of Y~X1+X2, ...
1
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0answers
44 views

Unexpected correlation, Method to account for the shared variance

Summary: While looking at the correlations I noticed a wired, relation. Variables: User comments - A; User community activity- B; Comments on user's wall - C (control) I expected that A and B will ...
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0answers
25 views

Base model regression with controls

Summary: I have a regression model hypothesizing mediation effect. Next to the variables I am interested to, I also have few control variables. First I want to express the base regression model. Then ...
1
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1answer
574 views

Covariates considered moderator or control variables?

Are covariates considered moderator variables or control variables? To elaborate on my question, I'm conducting a research study which has: variables that are supposed to affect the dependent ...
0
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0answers
224 views

How to control for categorical variable in SEM?

I have a categorical control variable (say, project type) and a continuous DV (latent with 6 observed variables). How do I best control for the effect of project type on the latent DV?
2
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1answer
82 views

Pros and cons of controlling for age when examining effect of cognition on driving performance

I am reviewing some studies on the relationship between cognition and driving. Some studies have controlled for age and some have not (age is correlated with cognition. Can anyone please provide any ...
2
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1answer
132 views

How to control for a variable

The goal of the analysis is to find a correlation between birth context and stature, while controlling for age. Each person has an ID number, age, stature, and birth context. That last part is what ...
0
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0answers
69 views

Too many controls?

I am purposely keeping this question vague since this has happened to me with multiple datasets. I have a DV and a few IV then several controls, and all looks fine. Then I add one more controls and ...
0
votes
1answer
123 views

Partial correlation

I want to create a regression model to predict state crime rate. There are two variables among 10 ( Vi= # of violent crimes per 100,000 population, Vi2 = # of violent crimes per 10,000 population) ...
0
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2answers
45 views

How to determine influence of two time series with feedback?

Say you have two time series, A & B. Each have a mutual effect on the other. To give a real-world example, say that time series A measures an artist's CD sales per month, and time series B is some ...
1
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1answer
116 views

Dividing controls between two groups of cases

I have a set of data that contains cases and controls. I would like to divide the cases by a particular phenotype before running my tests, to see how these groups differ (but not necessarily to ...
1
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1answer
346 views

What if only control variables are significant in a differences-in-differences analysis?

Regarding the standard DID model: $$ y=\alpha+\beta_1\text{treat}+\beta_2\text{post}+\beta_3\text{treatâ‹…post}+u $$ What exactly does it mean if say $\beta_3$ is not statistically significant, but ...
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3answers
122 views

What is the link between methods such as matching and statistically controlling for variables?

Often in research articles you read the researchers have controlled for certain variables. This can be done by methods such as matching, blocking, etc. But I always thought controlling for variables ...
0
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1answer
132 views

controlling for a highly correlated variable

In a paper looking at hand movements and time taken to complete a task it appears that the ratio of movements over time is constant (i.e., movement and time are highly correlated) yet they say in the ...
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3answers
930 views

How to control for market return in an (SPSS) OLS?

Please consider the following panel dataset: ...
1
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1answer
219 views

Interpreting Omitted Variables

I do not fully understand how to interpret the difference between two statistical models where they only differ based on whether a certain variable is included on the right hand side. If the results ...