Questions tagged [modeling]
This tag describes the process of creating a statistical or machine learning model. Always add a more specific tag.
2,626 questions
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Advice on regression approach
How should I handle a mass-point in the dependent variable when running OLS regression in R?
I’m working with a a household expenditure dataset (Living Costs 2019) where the dependent variable is the ...
- 31
2
votes
1
answer
46
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Pattern analysis for time between events data
I am trying to subset data based on a pattern of "strings" or clusters of food deliveries to young that I see in my data (see plots labeled 2, 4, 5, 6, and 8 in the figure below for the most ...
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1
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0
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16
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Modelling profile over time when changing start point
I have data in JMP which is formatted with columns (simplified):
Sample name
Initial value
Value after 4 weeks
Value after 8 weeks
Value after 12 weeks
I have 200+ rows
My aim is to model all of ...
- 11
5
votes
3
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533
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How to handle outliers when some predictors perform better with them and others without
I’m working on a project where I need to build a predictive model for wine quality based on its chemical properties. The goal is to find which features best explain or predict the quality score.
I’ve ...
- 51
0
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0
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60
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What kind of time series model am I working with? (EView)
I am taking a mandatory Time Series class at university. The professor's lecture slides, reading materials, and seminar training are all the more confusing. He also refuses to answer any kind of ...
- 21
4
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1
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125
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3
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1
answer
89
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measurement invariance with theta and lisrel parameterization
I’m trying to test a model of threshold invariance for ordinal indicators across 6 time points using semTools::measEq.syntax() with
parameterization = "theta",
ID.cat = "...
- 359
2
votes
1
answer
71
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Dataset for CFA and EFA
I first performed an Exploratory Factor Analysis (EFA) to identify the number of factors and the pattern of loadings. Then, using the same dataset (5165 observations), I conducted a Confirmatory ...
- 359
2
votes
1
answer
98
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Clarification on parameterizations in lavaan for measurement invariance
I’m using lavaan in R to test measurement invariance of a factor model. I’ve seen that lavaan allows different parameterizations ("standard" and "theta" via the parameterization ...
- 359
6
votes
1
answer
142
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GAMM with a global smooth term and site-specific deviations with concurvity present (mgcv::gam())
I’m fitting generalized additive mixed models in R (mgcv::gam()) to study how productivity changes over time across multiple Locations.
Each Location has repeated measurements from several plots. I ...
- 175
5
votes
1
answer
162
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Strange pattern of fit indices in Measurement invariance testing
I am testing measurement invariance across 7 time points using WLSMV since my indicators are ordinal. Here are my results:
When I impose threshold constraints, the overall fit indices get worse (...
- 359
5
votes
1
answer
188
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Why do GAMM partial effects have such different scales across distributions (Tweedie vs Gaussian)?
I’m fitting generalized additive mixed models (GAMMs) using mgcv::gam() in R, and I’ve run into a question about the scale of model outputs.
The goal of my analysis ...
- 175
1
vote
1
answer
64
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Autoregressive Latent Trajectory with Structured Residuals
I'm trying to estimate an ALT-SR model (autoregressive latent trajectory with random intercepts) where stress is continuous and smoke is ordinal (0/1).
When I run the model I get the following warning:...
- 359
4
votes
1
answer
101
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cross-lagged panel model (lavaan)
I am modelling the longitudinal relationships between three observed variables:
behavior (binary: 0/1)
affect (continuous)
wellbeing (5-point Likert scale)
The baseline year is 2008, and I have ...
- 359
2
votes
2
answers
144
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Clarification on Δχ² interpretation for metric invariance with WLSMV and Svetina et al. (2019)
I'm performing measurement invariance testing across six groups using lavaan with categorical data (4-point Likert), the WLSMV estimator, and the delta parameterization with Wu & Estabrook (2016) ...
- 359