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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   0.544 -2.77  9.60e- 4 0.159    0.544
#>  2 1              2   2.03   0.740 2.10e- 1 0.610    2.03 
#>  3 1              3   3.44   4.25  8.76e- 2 0.747    3.44 
#>  4 1              4   1.83   7.75  9.92e- 3 0.580    1.83 
#>  5 1              5   2.01  11.3   1.34e- 5 0.607    2.01 
#>  6 1              6 166.    14.8   1.75e- 3 0.994  166.   
#>  7 1              7   1.15  18.3   6.77e- 3 0.418    1.15 
#>  8 1              8   0.428 21.8   2.85e- 7 0.0966   0.428
#>  9 1              9   3.70  25.3   8.73e-17 0.763    3.70 
#> 10 1             10   0.978 28.8   1.78e-19 0.360    0.978
#> # … with 40 more rows