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error in `contrasts<-`(`*tmp*`, value = contr.funs[1 + isOF[nn]]) : contrasts can be applied only to factors with 2 or more levels, in R - Stack Overflow
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Deep convolutional neural networks to predict cardiovascular risk from computed tomography | Nature Communications
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Smart computational light microscopes (SCLMs) of smart computational imaging laboratory (SCILab) | PhotoniX | Full Text
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![R gives me the error "contrasts can be applied only to factors with 2 or more levels" running an mlogit model, but all my factors have 2 levels - Cross Validated R gives me the error "contrasts can be applied only to factors with 2 or more levels" running an mlogit model, but all my factors have 2 levels - Cross Validated](https://i.stack.imgur.com/3bk85.png)
R gives me the error "contrasts can be applied only to factors with 2 or more levels" running an mlogit model, but all my factors have 2 levels - Cross Validated
![Smart computational light microscopes (SCLMs) of smart computational imaging laboratory (SCILab) | PhotoniX | Full Text Smart computational light microscopes (SCLMs) of smart computational imaging laboratory (SCILab) | PhotoniX | Full Text](https://media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs43074-021-00040-2/MediaObjects/43074_2021_40_Fig1_HTML.png)
Smart computational light microscopes (SCLMs) of smart computational imaging laboratory (SCILab) | PhotoniX | Full Text
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Factors associated with deaths due to COVID-19 versus other causes: population-based cohort analysis of UK primary care data and linked national death registrations within the OpenSAFELY platform - The Lancet Regional Health –
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