All Questions
3,130 questions
1
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1
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27
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Why are two CFA models not equivalent if I drop some variables from my dataframe or restrict factor loadings to 0, keeping all variables? lavaan
Exploring nested vs. non-nested models, I was surprised with a strange result. The first model uses 21 variables from my dataframe and runs a CFA. The second model uses 28 variables from my dataframe, ...
- 194
1
vote
2
answers
30
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Should I conduct a multilevel for this or another analysis? Need help
I have three sources of data (teachers, parents and students) assessing students, in three waves. I want to assess all and see the differences between moments but then I also want to use variables for ...
0
votes
0
answers
16
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Negative Lambda in box/cox: Caveats and Interpretation [closed]
I have a highly-skewed DV which has not responded well to standard transformations (square root, cubed root, log or ln, hyperbolic arcsine).I do get some reduction in skew, but not enough to normalize ...
-1
votes
0
answers
8
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what happens when a network has low closeness centrality - what happens to nodes on the periphery [closed]
I have thirty-nine nodes with closeness centrality scores but I do not know what to say about the nodes on the periphery who do not have scores.
3
votes
1
answer
46
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Calculate marginal effects for random effects model with two crossed random effects
I am trying to get effects marginal of two crossed random effects (using STAN or brms). I understand how to do it for a single random effect following McElreath's book and Kurtz's brms version of the ...
4
votes
2
answers
41
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Accounting for non-independence and autocorrelation in HGAM
I am currently trying to fit a HGAM to model differences in daily activity patterns of fish in two treatments. Data were collected with high-resolution telemetry, and I currently have estimates of ...
- 105
1
vote
1
answer
33
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Modeling longitidunal relationships without estimating indirect effects
I'm analyzing a three-time point study using structural equation modeling (SEM). I only care about the direct effects of my variables. Is it okay to only model those direct paths, or should I include ...
- 13
0
votes
0
answers
22
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Derive gamma-parameters from preset R^2 in mixed models
For a simulation study in R, I want to select the effect sizes according to a preset $R^2$.
Consider this two level random intercept mixed model, with one L1 predictor $X_{ij}$ and one L2 predictor $...
- 153
0
votes
0
answers
7
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Prediction with categorical data in semopy [migrated]
I'm using semopy for the first time (I am more familiar with lavaan in R). I was able to apply the ...
- 119
0
votes
0
answers
9
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Extracting individual level posterior class memebership probabilities in multilevel LCA
I am conducting a multilevel laten class analysis using the R package multilevLCA.
I have fitted the model using multiple steps (i.e. determining optimal number of classes as well as clusters). I now ...
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2
votes
2
answers
28
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Calculating path coefficients manually from correlations
As I understand it, in a path model, we can use Wright's approach to manually calculate (standardized) path coefficients from the correlations between the variables. In the saturated case, we ...
- 41
6
votes
1
answer
125
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Is there a way to forecast by subgroup without forecasting each subgroup separately?
I am trying to find an appropriate model to forecast the number of applications received at the end of a recruitment cycle based on previous recruitment cycles and the number of applications received ...
1
vote
0
answers
34
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Errors in constructing SEM using lavaan package
I’m looking for a second set of eyes to help diagnose the issues I am having with my SEM model:
Here is my SEM code:
...
- 203
1
vote
0
answers
48
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Opposite results using Bayesian (STAN) vs Multilevel model (nlme). How is this possible?
My datasets contains the median wages and the cumulative installed wind-capacity for 4000 counties over a period of 20 years. The wages tend to rise over the period and the capacity tends to highly ...
- 11
1
vote
0
answers
61
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Causal Discovery Packages Supporting Mixed Data Types and Prior Knowledge
I am new to the field of Causal Discovery and would like to apply standard algorithms to my dataset, which contains both categorical and continuous variables. I am looking for Python packages that can ...
- 63
0
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0
answers
18
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How to Forecast Sales for Sub-Locations Without Historical Proportion Data?
I have a time series dataset of total sales for a product in a store over time. This product is available in two different locations within the store: one stand near the checkout and another stand in ...
1
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0
answers
14
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How many clusters are needed for applying cluster-robust standard errors in a SEM model?
I’m working on an SEM model with data from 1078 students, distributed across 13 schools (clusters). I’d like to apply cluster-robust standard errors, but I’m unsure whether 13 clusters is enough for ...
- 81
1
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0
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92
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Best way to report indirect effects in a complex Structural Equation Model (SEM) with a large number of variables and paths
I am fitting a complex structural equation model (SEM) with 4 latent and 2 observed variables (15 direct and 36 indirect effects). Importantly, in this model, some indirect effects from a given ...
- 79
2
votes
0
answers
38
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Handling Underrepresented Gender Categories in SEM [closed]
I’m including gender as a covariate in my SEM. My data consists of 1,078 cases
with 29 "Prefer not to say" and 8 "Diverse gender".
I’ve treated "Prefer not to say" as NA. ...
- 81
0
votes
0
answers
24
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Multilevel Model in R
I have data from a study in which 19 participants (9 males, 10 females) have each completed 4 jumping conditions (BW, 20, 25, 30) whilst I have measured joint level data for the hip, knee and ankle. I ...
- 1
2
votes
1
answer
86
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Structural Equation Modelling - Semopy
I have created some simulated data. To keep things simple, lets say I have done the following:
y = (X_1 + X_2 + X_3)/3 + e
Where each X_i is drawn from a normal distribution and I have added ...
- 93
0
votes
1
answer
42
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CWC(M) in multilevel modeling
I am new to multilevel modeling and recently learned about CWC(M) by Zhang et al. (2009, https://journals.sagepub.com/doi/abs/10.1177/1094428108327450). I am running a multitlevel moderated mediation ...
- 1
0
votes
0
answers
92
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Using classifier prediction as independent variable with within-subjects data?
In my work I've stumbled upon an interesting result when a classifier is applied to within-subjects data. My question is whether this is a known result, and if so, does it have a name? I can't find ...
- 1,944
7
votes
2
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254
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Can you have bidirectional correlation in path analysis?
Something like this:
Where B causes A, C causes D, and A and D are directly correlated.
Is it possible to solve a system like this?
- 375
1
vote
1
answer
28
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Path analysis indirect correlation highly correlated to direct one. Is this expected? [closed]
Assume B has a direct effect on A and C has a direct on A as well. Here γ, α and β are the corresponding correlations. β is an indirect "artificial" correlation and γ*α is "true" ...
- 375
0
votes
0
answers
12
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mice multilevel imputation: does specifying cluster variable ("-2" in predictor Matrix) without multilevel methods lead to cluster robust imputation?
In short: Are mice's imputations cluster robust when I only specify the cluster variable with "-2" in the predictor matrix but do not use multilevel models during imputation?
For clustered ...
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3
votes
1
answer
40
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Is it possible to model a Second-order growth slope factor as a mediator of another second-order growth slope factor?
I am running a second-order growth model with three variables.
My data spans 7 waves of data. I am currently running a multivariate growth model
which models the associative relation of multiple ...
- 31
11
votes
4
answers
647
views
Generally, are we supposed to remove all nonsignificant paths in an SEM analysis?
Given that we favour parsimony in science, should we remove nonsignificant paths that are nonsignificant if they do not result in significantly worse model fit?
After we remove the nonsignificant ...
- 331
4
votes
1
answer
45
views
How to Simulate a Multilevel Predictor Variable with Both L1 and L2 Variance Components?
I'm working on simulating multilevel data where I have a predictor variable measured at Level 1 (L1), which has both L1 and L2 variance components. For example, I want to simulate a socio-economic ...
- 153
5
votes
1
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229
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In SEM, is there any point in interpreting path coefficients if the model shows poor fit in the first place?
If there were some path coefficients that were significant but the whole model shows poor fit, can I still use the result from the significant path?
By extension, if the model evidenced poor fit in ...
- 331
2
votes
1
answer
35
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Reporting Hierarchical Regression Results in Abstract
I did a hierarchical regression test in a social science study looking at how two variables (A and B) and their interaction term can predict variable C. My mentor told me to write in the abstract that ...
- 21
1
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1
answer
55
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How/where to add covariates in SEM mediation model (lavaan)?
Say I have a predictor X, a mediator M, and an outcome Y. I also have a covariate W1 that I assume to have a direct effect on X and M (based on conceptual closeness and empirical findings) but not ...
4
votes
2
answers
156
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Path Analysis with a variable use d as grouping variable and predictor at the same time
I am conducting path analysis using structural equation modeling (SEM) and have a question regarding the use of a grouping variable in my model. One of my key longitudinal hypotheses is whether the ...
- 41
0
votes
1
answer
33
views
Mediation models require a sigma matrix that is symmetric
I'm trying to fit the following reproducible mediation model called final. But I get an error saying:
sigma must be a symmetric matrix
Could you please advise how ...
- 397
2
votes
1
answer
28
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Second-Order Latent Variable in SEM
I am planning to examine the effect of instructional quality on well-being using SEM. Well-being is conceptualized as consisting of five dimensions, with the possibility of calculating a general ...
- 81
2
votes
0
answers
16
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Which estimator to choose for meta-analysis^ REML or CR2 with Wild Bootstrap?
I am following the following book: https://bookdown.org/MathiasHarrer/Doing_Meta_Analysis_in_R/multilevel-ma.html
I can't choose which estimator to choose: REML or CR2 with Wild Bootstrap.
Or maybe ...
- 21
3
votes
1
answer
61
views
How can we simulate correlated random variables that vary at different levels in a multilevel/mixed effects setting?
I am very familiar with generating correlated random variables from a multivariate normal distribution.
This question is about doing that in a multilevel setting, where variables only vary at ...
- 65.8k
2
votes
1
answer
78
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General formula for mixed models
I'm trying to wrap my head around the general formula of mixed models and how it relates to the system of equations I'm used to.
The general formula read like this:
$$\mathbf{Y_{j}}=\mathbf{X_{j} \...
- 153
2
votes
2
answers
99
views
Dealing with Two-Item Factors in CFA
I am setting up a latent variable model for a CFA in lavaan (R), with plans to use the measurement model in a subsequent SEM analysis. The model includes five correlated factors, each with 3-4 ...
- 81
4
votes
1
answer
39
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Outcome in mixed models - lower level or upper level?
I am learning about mixed models and I have a question regarding the outcomes that can be considered. If I have hierarchical data, do the outcomes that I can consider need to belong to the lower level?...
- 43
2
votes
1
answer
36
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How should you specify a bifactor SEM, where one factor only has one item?
I am trying to respecify an SEM in R using the lavaan package to improve model fit. After inspecting the standardized residuals I noticed that item injnorm2 is formulated in conjunctive (i.e. using ...
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8
votes
1
answer
471
views
Power analysis for three-level multilevel models in R
For a study in a social science setting - where huge number of participants are not easily available - I'm trying to do a power analysis for a three-level multilevel design.
There are few packages ...
- 153
3
votes
1
answer
90
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All correlations meta-analysis
I am new with MetaSEM. I am trying to fit a simple meta-analysis (I just want to analyse 2 correlations; see Figure).
Here you can find the code that I am using with some simulated data but if there ...
- 73
1
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0
answers
15
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How to Set Up a Polynomial Multilevel Model
I have a modeling situation that I am not 100% sure how to approach. I have two independent variables, information and time, with time being a repeated measure. The dependent measure is difference. ...
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0
votes
1
answer
36
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Modeling approaches for conditional probability distribution, applied to Propensity Score estimation for IPW (causal inference)
I'm trying to understand and ideally implement the Inverse Probability Weighting approach to estimate a causal effect. My ressources so far have been Pearl's Primer and the book "What If?".
...
- 225
3
votes
1
answer
24
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Can I replicate SEM results with only variance-covariance matrix of the summated scores?
I am trying to replicate structural equation modeling results from some research papers using just the variance-covariance matrix.
If the authors estimated the models using observed variables from the ...
- 331
1
vote
1
answer
56
views
Multi-level modelling?
In an instructional study, I have pretest and post-test measures of writing quality--no control condition. There are 110 students nested in 10 classes. I have pretest measures of spelling skill and ...
- 13
1
vote
0
answers
62
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Prediction Intervals With Hierarchical Regression Model
I'm reading this data analysis book by Gelman and Hill and am trying to understand predictions with hierarchical models. On page 273 they are demonstrating making new predictions for an already ...
- 133
1
vote
1
answer
47
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Mixed Effects CFA using R and lavaan
I want to conduct a CFA with 3 factors and 9 items each. The data contains cluster of highly varying size. (1 < n < 40, 90 clusters in total while 40 clusters only have one observation). I ...
- 11
0
votes
1
answer
42
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(R) Second-order latent variable CFA not providing standard errors, one variance is negative
I am going to run an SEM model of one second-order latent variable, parental stress, which is made up by two first-order latent variables. Before I run the SEM model, I am verifying the measurement ...
- 11