effects package does not work with logical variables

Create outcome data

## Annette Dobson (1990) "An Introduction to Generalized Linear Models".
## Page 9: Plant Weight Data.
ctl <- c(4.17,5.58,5.18,6.11,4.50,4.61,5.17,4.53,5.33,5.14)
trt <- c(4.81,4.17,4.41,3.59,5.87,3.83,6.03,4.89,4.32,4.69)
weight <- c(ctl, trt)

Create binary predictor as factor, logical, and numeric

group.factor  <- gl(2,10,20, labels=c("Ctl","Trt"))
group.logical <- group.factor == "Trt"
group.numeric <- as.numeric(group.logical)

Perform linear regression for each

lm.factor  <- lm(weight ~ group.factor)
lm.logical <- lm(weight ~ group.logical)
lm.numeric <- lm(weight ~ group.numeric)

list(summary(lm.factor),
     summary(lm.logical),
     summary(lm.numeric))

[[1]]

Call:
lm(formula = weight ~ group.factor)

Residuals:
    Min      1Q  Median      3Q     Max 
-1.0710 -0.4938  0.0685  0.2462  1.3690 

Coefficients:
                Estimate Std. Error t value Pr(>|t|)    
(Intercept)        5.032      0.220   22.85  9.5e-15 ***
group.factorTrt   -0.371      0.311   -1.19     0.25    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 

Residual standard error: 0.696 on 18 degrees of freedom
Multiple R-squared: 0.0731, Adjusted R-squared: 0.0216 
F-statistic: 1.42 on 1 and 18 DF,  p-value: 0.249 


[[2]]

Call:
lm(formula = weight ~ group.logical)

Residuals:
    Min      1Q  Median      3Q     Max 
-1.0710 -0.4938  0.0685  0.2462  1.3690 

Coefficients:
                  Estimate Std. Error t value Pr(>|t|)    
(Intercept)          5.032      0.220   22.85  9.5e-15 ***
group.logicalTRUE   -0.371      0.311   -1.19     0.25    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 

Residual standard error: 0.696 on 18 degrees of freedom
Multiple R-squared: 0.0731, Adjusted R-squared: 0.0216 
F-statistic: 1.42 on 1 and 18 DF,  p-value: 0.249 


[[3]]

Call:
lm(formula = weight ~ group.numeric)

Residuals:
    Min      1Q  Median      3Q     Max 
-1.0710 -0.4938  0.0685  0.2462  1.3690 

Coefficients:
              Estimate Std. Error t value Pr(>|t|)    
(Intercept)      5.032      0.220   22.85  9.5e-15 ***
group.numeric   -0.371      0.311   -1.19     0.25    
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 

Residual standard error: 0.696 on 18 degrees of freedom
Multiple R-squared: 0.0731, Adjusted R-squared: 0.0216 
F-statistic: 1.42 on 1 and 18 DF,  p-value: 0.249 

Create allEffects plot for each

library(effects)
plot(allEffects(lm.factor))

plot(allEffects(lm.logical))

Error: error in evaluating the argument 'x' in selecting a method for function 'plot': Error in mod.matrix %*%
mod$coefficients : non-conformable arguments Calls: allEffects -> allEffects.default -> lapply -> FUN -> effect.lm

plot(allEffects(lm.numeric))