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Problem

I've been using a tidy wrapper for the drc package—tidydrc— to build growth curves which produces a tidy version of the normal output (best for ggplot). However, due to the inherit nesting of the models, I can't run simple drc functions since the models are nested inside a dataframe. I've attached code that mirrors drc and tidydrc package below.

Goal

To compare information criteria from multiple model fits for the tidydrc output using the drc function mselect()—ultimately to efficiently select the best fitting model.

Ideal Result (works with drc)

library(tidydrc) # To load the Puromycin data
library(drc)

model_1 <- drm(rate ~ conc, state, data = Puromycin, fct = MM.3())

mselect(model_1, list(LL.3(), LL.5(), W1.3(), W1.4(), W2.4(), baro5()))


# DESIRED OUTPUT SIMILAR TO THIS
         logLik       IC Lack of fit  Res var
MM.3  -78.10685 170.2137   0.9779485 70.54874 # Best fitting model
LL.3  -78.52648 171.0530   0.9491058 73.17059
W1.3  -79.22592 172.4518   0.8763679 77.75903
W2.4  -77.87330 173.7466   0.9315559 78.34783
W1.4  -78.16193 174.3239   0.8862192 80.33907
LL.5  -77.53835 177.0767   0.7936113 87.80627
baro5 -78.00206 178.0041   0.6357592 91.41919

Not Working Example with tidydrc

library(tidyverse) # tidydrc utilizes tidyverse functions

model_2 <- tidydrc_model(data = Puromycin, conc, rate, state, model = MM.3())
summary(model_2)

Error: summary.vctrs_list_of() not implemented.

Now, I can manually tease apart the list of models in the dataframe model_2 but can't seem to figure out the correct apply statements (it's a mess) to get this working.

Progress Thus Far

These both produce the same error, so at least I've subsetted a level down but now I'm stuck and pretty sure this is not the ideal solution.

mselect(model_2$drmod, list(LL.3(), LL.5(), W1.3(), W1.4(), W2.4(), baro5()))

model_2_sub <- model_2$drmod # Manually subset the drmod column

apply(model_2_sub, 2, mselect(list(LL.3(), LL.5(), W1.3(), W1.4(), W2.4(), baro5())))

Error in UseMethod("logLik") : no applicable method for 'logLik' applied to an object of class "list"

I've even tried the tidyverse function unnest() to no avail

model_2_unnest <- model_2 %>% unnest_longer(drmod, indices_include = FALSE)
TheSciGuy
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    Can you please provide the desired output? – tmfmnk Feb 14 '20 at 18:40
  • The desired output would be the similar to the result from first section of code that I posted: "**Ideal Result (works with `drc`)**" or something very similar. This might be unachievable because `tidydrc` makes lists of the models. I just need to unnest those lists and then run the `drc` function `mselect()` to compare model information criteria such as "logLik, IC, Lack of fit, and Res var". – TheSciGuy Feb 14 '20 at 20:10

0 Answers0