diff --git a/src/extractor/AmrexCastro.jl b/src/extractor/AmrexCastro.jl
index 9bf31ac6fd67acf00135a9df3607b6563515f13d..4def44e6a40bd6e03a17f5b4fc1f4d0fc091dce5 100644
--- a/src/extractor/AmrexCastro.jl
+++ b/src/extractor/AmrexCastro.jl
@@ -24,7 +24,7 @@ struct AmrexCastro <: AbstractAmrex
             "castro.max_grid_size",
         ],
         Dict{String,Array{String}}(
-            "plots_size" => ["amr.nplot_files", "amr.ncells", "amr.max_level"],
+            "plots_size" => ["amr.nplot_files", "amr.ncells"],
             "checks_size" => [
                 "amr.check_int",
                 "amr.ncheck_files",
@@ -128,21 +128,31 @@ function _run_linear_model_plots_size(extractor::AmrexCastro, X::DataFrames.Data
         push!(plotsSizesData, [plotsSize])
     end
 
+    println(plotsSizesData)
+    
     # Prepare the X independent variables in the linear model
     XNames::Array{String} = extractor.outputs["plots_size"]
-
-    for XName in XNames
-        columnName = Symbol(XName)
+      
+   col1 = Symbol("amr.nplot_files")
+   col2 = Symbol("amr.ncells")
+   
+   insert!(plotsSizesData, 2 ,X[!,col1] .* X[!,col2], :new_data) 
+   #plotsSizesData[!,col1] = 
+    
+                                    
+
+    #for XName in XNames
+        #columnName = Symbol(XName)
         # this syntax [!, symbol] does not make a copy, use [:, symbol] for copies
-        plotsSizesData[!, columnName] = X[!, columnName]
-    end
+        #plotsSizesData[!, columnName] = X[!, columnName]
+    #end
 
     # formula from https://discourse.julialang.org/t/glm-jl-with-unknown-column-names/20692/5
     response = Symbol(names(plotsSizesData)[1])
     predictors = Symbol.(names(plotsSizesData)[2:end])
 
     println(plotsSizesData)
-    f = @eval(GLM.@formula($response ~ (+)(1, $(predictors...))))
+    f = @eval(GLM.@formula($response ~ (+)( $(predictors...))))
 
 
     ols = GLM.lm(f, plotsSizesData)