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This function will generate n random points from an inverse gamma distribution with a user provided, .shape, .rate, .scale, and number of random simulations to be produced. The function returns a tibble with the simulation number column the x column which corresponds to the n randomly generated points, the d_, p_ and q_ data points as well.

The data is returned un-grouped.

The columns that are output are:

  • sim_number The current simulation number.

  • x The current value of n for the current simulation.

  • y The randomly generated data point.

  • dx The x value from the stats::density() function.

  • dy The y value from the stats::density() function.

  • p The values from the resulting p_ function of the distribution family.

  • q The values from the resulting q_ function of the distribution family.

Usage

tidy_inverse_gamma(
  .n = 50,
  .shape = 1,
  .rate = 1,
  .scale = 1/.rate,
  .num_sims = 1,
  .return_tibble = TRUE
)

Arguments

.n

The number of randomly generated points you want.

.shape

Must be strictly positive.

.rate

An alternative way to specify the .scale

.scale

Must be strictly positive.

.num_sims

The number of randomly generated simulations you want.

.return_tibble

A logical value indicating whether to return the result as a tibble. Default is TRUE.

Value

A tibble of randomly generated data.

Details

This function uses the underlying actuar::rinvgamma(), and its underlying p, d, and q functions. For more information please see actuar::rinvgamma()

Author

Steven P. Sanderson II, MPH

Examples

tidy_inverse_gamma()
#> # A tibble: 50 × 7
#>    sim_number     x     y     dx       dy      p     q
#>    <fct>      <int> <dbl>  <dbl>    <dbl>  <dbl> <dbl>
#>  1 1              1 2.55  -1.68  8.94e- 4 0.676  2.55 
#>  2 1              2 2.90   0.568 3.36e- 1 0.709  2.90 
#>  3 1              3 0.322  2.81  1.39e- 1 0.0447 0.322
#>  4 1              4 2.54   5.06  3.37e- 2 0.675  2.54 
#>  5 1              5 1.33   7.30  1.37e- 2 0.470  1.33 
#>  6 1              6 2.18   9.55  5.38e- 3 0.632  2.18 
#>  7 1              7 0.907 11.8   9.91e- 8 0.332  0.907
#>  8 1              8 2.77  14.0   1.27e-17 0.697  2.77 
#>  9 1              9 0.262 16.3   0        0.0218 0.262
#> 10 1             10 0.526 18.5   0        0.150  0.526
#> # ℹ 40 more rows