Compute exact partition function

For Cayley, Hamming, and Kendall distances, computationally tractable functions are available for the exact partition function.

Usage

compute_exact_partition_function(
  alpha,
  n_items,
  metric = c("cayley", "hamming", "kendall")
)

Arguments

alpha

Dispersion parameter.

n_items

Number of items.

metric

Distance function, one of "cayley", "hamming", or "kendall".

Value

The logarithm of the partition function.

References

See also

Other partition function: estimate_partition_function(), get_cardinalities()

Examples

compute_exact_partition_function(
  alpha = 3.4, n_items = 34, metric = "cayley"
)
#> [1] 85.60544

compute_exact_partition_function(
  alpha = 3.4, n_items = 34, metric = "hamming"
)
#> [1] 85.286

compute_exact_partition_function(
  alpha = 3.4, n_items = 34, metric = "kendall"
)
#> [1] 65.91866