A situation where the effect of an explanatory variable may depend on the value of another explanatory variable.

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1answer
32 views

Curvilinear relationship with moderator

I am trying to moderate a curve and determine which equation I should follow. A simple curvilinear relationship has the following equation: (1) $Y = b_0 + b_1X + b_2X^2$ (i.e. a linear term and a ...
2
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2answers
21 views

Imputing using CFA for use in a Cox regression

I am using CFA (confirmatory factor analysis) to create a measurement model of social capital that is to be used in a Cox regression. Because of missing data I first impute the incomplete data by MICE ...
-1
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0answers
9 views

Moderating a curve [on hold]

I have a paper that has a main relationship with a negative curve. It actually looks like a left leaning hockey stick. We have three moderators - two that strengthen the negative slope and one that ...
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0answers
21 views

What is a good mouse cursor to point at objects in diagrams? [on hold]

Do you know of any study or evaluation of the use of mouse cursors specifically designed for the use in diagrams? For example I'm thinking about using a cross hair instead of an arrow cursor when I ...
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0answers
10 views

Performing interaction with a very significant predictor drives down p val of other predictors. But does it makes sense?

I'm observing a phenomenon that I can't understand. I have a linear regression setting with categorical vars. A couple of these elicit an highly significant coefficient and low p values. When used ...
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0answers
12 views

PROCESS (Hayes) by using IV categorical

I am trying to run a moderation using SPSS with Hayes'macro. But I have a IV with 3 categories (a,b,c). In his page Hayes gives this explanation (see below) but I am not sure how to do this using ...
2
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1answer
11 views

What's the best way to model two insurance categories that are non-exclusive?

I am modeling insurance status in a logistic regression as separate dummy variables for private, Medicare, Medicaid, uninsured, etc. For people that are dual eligible, should I have a separate "dual ...
1
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0answers
11 views

How to analyze the interaction of temperature and PM on mortailtiy? [closed]

library(dlnm);library(mgcv);library(splines);library(tsModel) the model for main effect,(R code) ...
2
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2answers
25 views

Can a continuous effect modifier be categorized into quartiles? [duplicate]

Is it statistically sound to dummy code a continuous variable (effect modifier) into quartiles and compare the odds ratios of an IV vs. DV in Q1 and IV vs. DV in Q4 in logistic regression? If so, how ...
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0answers
15 views
0
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1answer
26 views

Multi level regression with interaction using R lme4

I'd like to do a regression analysis with interactions, my data has two levels (school classes and pupils). My variables are: Predictor = dummy variable on Level 1, dependent Variable = metric on ...
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0answers
19 views

how do we know if interaction effect exist between two continuous variables

I have a dependent variable (y) and three independent variables X1, X2, and X3. The correlation table shows that each of these independent variables has significant positive relationship with Y. But ...
1
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3answers
32 views

creating interaction term for dummy variables and categorical variables

I want to create interaction term by using dummy variables and categorical variables. For example, if I want to create interaction term by gender(0=male, 1=female) and education level(0=less than ...
0
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2answers
91 views

Multiple regression analysis - using all possible interactions

I have data on about 8000 persons and I am trying to find independent predictors of a health outcome variable (yvar). The predictor variables are age, gender, height, city and 3 other predictor ...
0
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1answer
104 views

How to interpret “main effects” in a GLMM?

Recently, I asked a question about what procedure to use to analyse mixed data with dichotomous outcomes, see [here][1]. Now I started running some first analyses (mainly with SPSS, but I'll post the ...
0
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0answers
40 views

In R package lme4, how do you force the random slopes and intercepts to be uncorrelated for an interaction term?

I have a mixed model, fit using lmer in R, that has three interaction terms (X1:X1, X1:X3, ...
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0answers
48 views

Meta-analysis of percent relative to baseline in R using metafor package

I would like to conduct a meta-anaylsis in the context where I have studies available that measure a continuos variable at multiple time points (0, 1, 2, 3, 4, 5). Time 0 represents the baseline at ...
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0answers
8 views

Including an interaction term in GLM with full factorial experiment data

I collected data from an 2 X 2 X 2 full factorial experiment. Because a DV is a count variable and unequal mean and variance, I ran a Negative Bimonial Model. It was hard for me to come up a good ...
0
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1answer
13 views

Prediction on Interaction Terms in Multiple Linear Model

I have created a MLR model where my predictor variables are continuous and categorical. I am interested in the interactions between the categorical variables. Let's say I have the response variable ...
1
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0answers
16 views

3-way repeated mesures ANOVA

I conducted reaction-time experiment with three factors - set size (4, 16, 64), presense of the target (present, absent) and the third factor with two levels (C, F). After that I ran a repeated ...
1
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1answer
31 views

How to report data when there is interaction

I did a multivariable logistic regression analysis to estimate the effect of an exposure (E) on an outcome while adjusting for confounders. I investigated interaction and discovered a significant ...
0
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1answer
46 views

How to explain when Main Effect and Interaction are not significant?

I've spent hours trying to interpret my data but I can't figure out how to explain the results when both the main effect and the interaction are not significant. I'm suppose to discuss my results, ...
0
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0answers
7 views

Testing for a 3-way interaction between a within-subjects factor, a continuous IV and a categorical IV in SPSS

I'd like to test whether the moderating effect of a (continuous) personality variable on the effect of an experimental manipulation differs between conditions. Does anyone know how to go about this in ...
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0answers
12 views

Identifying repeat interaction from two columns [migrated]

I have two columns which contain investment bank names in joint debt offerings. I want to create a dummy variable if the Bank 1 & Bank 2 have recurring relationships. Ex: if Lehman Brothers ...
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1answer
41 views

R adds unexpected variable to interaction model

Not sure if this is more of a programming question (in which case please move to stack overflow) or a statistical model question (in which case, please read on!) I'm exploring a data set and doing ...
2
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1answer
32 views

Interaction effect of 2x2 ANOVA in meta-analysis

I want to meta-analyze the interaction effect of a 2x2 ANOVA. (I am not talking about an interaction in the meta-regression, as in this question but about an interaction as the focal effect that ...
0
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1answer
24 views

Dropping the interaction term when the interaction effect is not significant?

Can I drop the interaction term from the model if the interaction term is insignificant?
0
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1answer
13 views

main effects of moderating variables

I am sorry if this is very trivial and a repetition. I could not find a direct question on the website that addresses my question I am studying the relationship between X1 (independent variable) and ...
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0answers
20 views

Can I interpret a simple slope if the product is not significant?

I used Hayes' PROCESS macro to run a simple regression. The interaction product was not significant (p=0.13) however the conditional effect (simple slope) was significant (at high levels of the ...
2
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1answer
53 views

Investigating interaction

Please I need to check for interaction before building an explanatory model (logistic regression). I have 16 interaction terms in total. Please how what is the best way to go about it. Will I need to ...
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3answers
60 views

Testing and reporting interactions in multiple regression

I have a model with two between-participants predictors -- one continuous (a), and one categorical with two levels (b) -- and ...
7
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2answers
93 views

How should I model interactions between explanatory variables when one of them may have quadratic and cubic terms?

I'm sincerely hoping that I have phrased this question in such a way that it can be definitively answered--if not, please let me know and I will try again! I should also I guess note that I will be ...
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0answers
31 views

Interaction with contrast and dummy coding

I have a question regarding the interpretation of an interaction using categorical variables where one is dummy coded (0, 1) and the other is contrast coded. The variables are: Var1: 3 levels, ...
0
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1answer
39 views

regarding the explanation of interaction plot

I was trying to draw an interaction plot for two predictor variables as follows: interaction.plot(xtest[,2],xtest[,8],y) I got the following plot. I do not know ...
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1answer
28 views

Interpretation of significant interaction

I look for an intuitive understanding of interaction effect in ANOVA or regression. Let's keep things simple as the following. Suppose we have a standard 2 x 2 factorial design, where each factor ...
1
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0answers
67 views

testing interaction terms in regression model [duplicate]

Based on domain knowledge and preliminary variable selection, we have decided a set of 10 variables as predictor variables for building regression models. What are the general approaches to identify ...
0
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1answer
19 views

Can moderators be affected by the manipulated/independent variable?

I was wondering whether I can use a measured variable as a moderator in a linear regression. Say I have a manipulated variable X, and two measured variables Y and Z. There is a main effect of X on Y, ...
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0answers
17 views

Do I need to concern the direction change of main effects when including in the interaction term?

I am fitting a GLIMMIX model with two treatment (outcome variable is binomial variable), say x1 and x2, each of which is a dichotomous variable. When x1 and x2 only were included in the model, the ...
2
votes
1answer
57 views

Closed form for the variance of a sum of two estimates in logistic regression?

In logistic regression with an intercept term and with at least one dependent variable which is categorical, is there a closed form for the variance of the sum of the intercept and the coefficient of ...
2
votes
1answer
89 views

How to implement ordinal logistic regression for a factorial design

I have read a few answers (e.g. this, this and this) recommending to use Ordinal Logistic Regression (OLR) as a generalized method when Kruskal-Wallis is not suitable. For instance, a 2x2 factorial ...
0
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1answer
24 views

How to deal with variable new behavior in multiple linear regression

Let's suppose that I have one model with 6 dummy variables for the days of the week and from those in 5 days a specific event happen, suppose that is daytostudy variable and I want to predict how many ...
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0answers
43 views

How to create dummy variables for interaction term between categorical variables?

I'm building a logistic regression model estimating the probability of hospitalization based on several predictor variables, including indicator variables for various diagnosis categories (coded as ...
0
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0answers
13 views

interpreting an interaction of two continuous variables in a mixed effects model [duplicate]

I am hoping for some guidance on how to interpret the interaction in a mixed effects model. The interaction is between two continuous variables (EarlyLanguageExposure and NeighborhoodSize). My ...
0
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1answer
36 views

Interaction Dummy

I have a model: $$ \ln({\rm earnings}) = 2.618656-0.0899657{\rm female}+0.382019{\rm white}-0.2754126{\rm female}\times{\rm white} $$ ${\rm female}$ and ${\rm white}$ are dummy variables. t= ...
0
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0answers
30 views

Dummy variable interpretation [duplicate]

I have a model: $$ \ln({\rm earnings}) = a+b_1{\rm female}+b_2{\rm white}+b_3{\rm female}\times{\rm white} $$ ${\rm female}$ and ${\rm white}$ are dummy variables. t= female=-1.65 white=8.86 ...
1
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1answer
81 views

Dummy variable interaction regression [duplicate]

I have a model: $$ \ln({\rm earnings}) = a+b_1{\rm female}+b_2{\rm white}+b_3{\rm female}\times{\rm white} $$ ${\rm female}$ and ${\rm white}$ are dummy variables. I have interpreted $b_1$ and $b_2$: ...
3
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1answer
92 views

Interpretation of interaction term

I have a model: $$ \ln({\rm earnings}) = a+b_1{\rm female}+b_2{\rm white}+b_3{\rm female}\times{\rm white} $$ ${\rm female}$ and ${\rm white}$ are dummy variables. I have interpreted $b_1$ and $b_2$: ...
0
votes
0answers
21 views

Cox proportional hazards (setting a reference level and an interaction with time)

I am currently trying to analysis some data in R using Cox proportional hazards. I have been able to get my coxph model to run but, I am having some coding difficulties. I have two factors (individual ...
0
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1answer
13 views

Citation for IV coefficient sign change with inclusion of interaction term

I have a two step regression model where I entered my three IVs in step 1 and one interaction in step 2. One of the IVs in the interaction has a positive coefficient in the first step and then a ...
2
votes
2answers
48 views

Interaction between a dummy variable and a variable with a quadratic form

I am finishing up an econometrics assignment and this problem has me stuck. I have estimated a regression equation for ln hourly wages on a gender dummy variable, several race dummy variables, a ...