log likelihood and derivatives for Geom distribution

Usage

llikGeom(x, prob, full = FALSE)

Arguments

x: variable distributed by a geom distribution
prob: probability of success in each trial. 0 < prob <= 1.
full: Add the data frame showing x, mean, sd as well as the fx and derivatives

Value

data frame with fx for the log pdf value of with dProb that has the derivatives with respect to the prob parameters at the observation time-point

Details

In an rxode2() model, you can use llikGeom() but you have to use the x and rate arguments. You can also get the derivative of prob with llikGeomDprob().

Author

Matthew L. Fidler

Examples


# \donttest{

llikGeom(1:10, 0.2)
#>           fx dProb
#> 1  -1.832581  3.75
#> 2  -2.055725  2.50
#> 3  -2.278869  1.25
#> 4  -2.502012  0.00
#> 5  -2.725156 -1.25
#> 6  -2.948299 -2.50
#> 7  -3.171443 -3.75
#> 8  -3.394586 -5.00
#> 9  -3.617730 -6.25
#> 10 -3.840873 -7.50

et  <- et(1:10)
et$prob <- 0.2
 
model <- function() {
  model({
    fx <- llikGeom(time, prob)
    dProb <- llikGeomDprob(time, prob)
  })
}

rxSolve(model, et)
#>  
#>  
#> ℹ parameter labels from comments are typically ignored in non-interactive mode
#> ℹ Need to run with the source intact to parse comments
#>  
#>  
#> using C compiler: ‘gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0’
#> ── Solved rxode2 object ──
#> ── Parameters (value$params): ──
#> # A tibble: 1 × 0
#> ── Initial Conditions (value$inits): ──
#> named numeric(0)
#> ── First part of data (object): ──
#> # A tibble: 10 × 4
#>    time    fx dProb  prob
#>   <dbl> <dbl> <dbl> <dbl>
#> 1     1 -1.83  3.75   0.2
#> 2     2 -2.06  2.5    0.2
#> 3     3 -2.28  1.25   0.2
#> 4     4 -2.50  0      0.2
#> 5     5 -2.73 -1.25   0.2
#> 6     6 -2.95 -2.5    0.2
#> # ℹ 4 more rows
# }