Error in stepwise backward selection

[aravindhebbali]

For the same model, ols_step_backward_p() works or throws error for different range of prem (p value threshold for removing a variable from the model) values.

# load package
library(olsrr)
#> 
#> Attaching package: 'olsrr'
#> The following object is masked from 'package:datasets':
#> 
#>     rivers

# model
model <- lm(y ~ age + gender + alc_mod, data = surgical)

# stepwise backward selection
# works
ols_step_backward_p(model, 0.2)
#> 
#> 
#>                            Elimination Summary                             
#> --------------------------------------------------------------------------
#>         Variable                  Adj.                                        
#> Step    Removed     R-Square    R-Square     C(p)       AIC         RMSE      
#> --------------------------------------------------------------------------
#>    1    age           0.0653      0.0286    2.4695    802.9616    380.6259    
#> --------------------------------------------------------------------------

# throws error
ols_step_backward_p(model, 0.1)
#> Error in str2lang(x): <text>:2:0: unexpected end of input
#> 1: y ~ 
#>    ^

^{Created on 2021-08-13 by the reprex package (v0.3.0)}