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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
)

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.

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  0.507 -1.85 1.13e- 3 0.139   0.507
#>  2 1              2  0.447  2.22 1.60e- 1 0.107   0.447
#>  3 1              3  2.38   6.30 1.57e- 2 0.657   2.38 
#>  4 1              4 15.0   10.4  1.23e- 5 0.936  15.0  
#>  5 1              5  4.41  14.5  2.52e- 2 0.797   4.41 
#>  6 1              6  1.73  18.5  7.63e- 7 0.561   1.73 
#>  7 1              7  2.35  22.6  2.24e-18 0.653   2.35 
#>  8 1              8  0.404 26.7  2.93e-11 0.0840  0.404
#>  9 1              9  0.722 30.8  9.74e- 3 0.250   0.722
#> 10 1             10  0.735 34.8  2.44e- 8 0.257   0.735
#> # ℹ 40 more rows