Maximum likelihood inference
Challenge
By looking at the (log) likelihoods for different dice models, try to work out which model fits best.
Is it the one where I blu-tacked 1 (so that 6 never turns up?). Or the one where I blu-tacked 4 (so that 3 never turns up)? Or another one?
Here is a way to do that using tribble() (a tibble specified row-wise) to put together the loglikeihood under all the
possible models:
loglikelihoods = tibble::tribble(
~model, ~loglikelihood,
"Normal dice", total_loglikelihood( data$sum_of_dice, rep( 1/6, 6 ) ),
"Omit 1", total_loglikelihood( data$sum_of_dice, c( 0.0, 0.2, 0.2, 0.2, 0.2, 0.2 ) ),
"Omit 2", total_loglikelihood( data$sum_of_dice, c( 0.2, 0.0, 0.2, 0.2, 0.2, 0.2 ) ),
"Omit 3", total_loglikelihood( data$sum_of_dice, c( 0.2, 0.2, 0.0, 0.2, 0.2, 0.2 ) ),
"Omit 4", total_loglikelihood( data$sum_of_dice, c( 0.2, 0.2, 0.2, 0.0, 0.2, 0.2 ) ),
"Omit 5", total_loglikelihood( data$sum_of_dice, c( 0.2, 0.2, 0.2, 0.2, 0.0, 0.2 ) ),
"Omit 6", total_loglikelihood( data$sum_of_dice, c( 0.2, 0.2, 0.2, 0.2, 0.2, 0.0 ) )
)
print( loglikelihoods )
We could plot that:
(
ggplot( data = loglikelihoods )
+ geom_point(
aes( x = model, y = loglikelihood )
)
+ theme(
axis.text.x = element_text( angle = 60, hjust = 1, vjust = 1 )
)
)
What does that mean?