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[Stable]

LogisticNormal is the class for the usual logistic regression model with a bivariate normal prior on the intercept and slope.

Usage

LogisticNormal(mean, cov, ref_dose = 1)

.DefaultLogisticNormal()

Arguments

mean

(numeric)
the prior mean vector.

cov

(matrix)
the prior covariance matrix. The precision matrix prec is internally calculated as an inverse of cov.

ref_dose

(number)
the reference dose \(x*\) (strictly positive number).

Details

The covariate is the natural logarithm of the dose \(x\) divided by the reference dose \(x*\), i.e.: $$logit[p(x)] = alpha0 + alpha1 * log(x/x*),$$ where \(p(x)\) is the probability of observing a DLT for a given dose \(x\). The prior $$(alpha0, alpha1) ~ Normal(mean, cov).$$

Note

Typically, end users will not use the .DefaultLogisticNormal() function.

Examples

# Define the dose-grid.
empty_data <- Data(doseGrid = c(1, 3, 5, 10, 15, 20, 25, 40, 50, 80, 100))

my_model <- LogisticNormal(
  mean = c(-0.85, 1),
  cov = matrix(c(1, -0.5, -0.5, 1), nrow = 2)
)

my_options <- McmcOptions(burnin = 10, step = 2, samples = 100)

samples <- mcmc(empty_data, my_model, my_options)
samples
#> An object of class "Samples"
#> Slot "data":
#> $alpha0
#>   [1] -2.82949518 -1.02917101 -1.29167752 -1.55700188 -3.22177256 -0.68794857
#>   [7] -1.90668250 -0.03341115 -0.31170864 -1.13596284 -0.05913492 -2.57962742
#>  [13]  1.34175697  0.19392927 -0.27504979 -1.25661078 -0.62397103 -1.38710576
#>  [19]  0.68044132 -0.10687252 -0.12441895 -1.81073385 -2.24296128 -0.07668373
#>  [25] -0.78150240  0.61720545 -0.57351003 -0.83516244 -0.53142721 -1.24189773
#>  [31] -1.76164563 -0.19342259 -0.05097796 -0.12235362 -2.33678300 -1.86789760
#>  [37] -0.56050861 -0.56968101 -0.19358889  0.35596115 -1.42745911  0.25651078
#>  [43] -1.20500096 -2.06927133 -2.31728151  0.66557573 -0.47118929 -2.07492020
#>  [49] -0.06524878 -0.66118853 -2.32939279 -0.70641193 -0.16073208  0.34878162
#>  [55] -1.84884026  0.09941423 -0.96746911 -0.77619353 -1.28263915 -0.22670391
#>  [61] -1.29673835  0.04723881  0.03080882 -0.49606501 -1.00477959 -1.69132369
#>  [67] -2.59326614 -1.35318552  1.00404536  0.57219418 -0.20959853 -0.87172893
#>  [73]  0.16553983 -0.43234660 -0.10204120 -1.55086149 -3.06977530 -0.02385605
#>  [79] -0.68243736 -1.05368443 -1.07844373 -0.21310344 -2.93671458 -0.85793555
#>  [85] -0.64686322 -0.53472655  0.37263481 -0.27354652 -0.44689751 -0.54590378
#>  [91] -2.01692296 -0.52448954 -0.55328782 -0.02215291 -1.04644483 -1.12629486
#>  [97]  0.72644346 -2.39596990 -1.48958993 -1.74883842
#> 
#> $alpha1
#>   [1]  0.84577657  1.13406930  1.27059126  2.70711409  2.97274660 -0.37764901
#>   [7]  2.78326246  0.24109395  0.79540947  2.08581480  2.06574877 -0.35203018
#>  [13] -1.79562865  0.50644514  0.65996682  2.46493181  0.91621213  0.61156991
#>  [19] -0.33779058  1.19729655  0.64951676  1.96070288  1.80584820  0.48180988
#>  [25]  1.43023314  0.60321716  0.95677785  0.49153265  1.00047031  0.60421015
#>  [31]  1.31537304  2.09064362  3.23369363  0.42050457  2.30590533  2.09369359
#>  [37]  0.23392451  1.03794048  1.09473970 -0.39161620  0.39703435  0.19639991
#>  [43]  0.91451091  1.71939755  2.50771184  0.78896948  0.21771350  0.08344010
#>  [49]  1.62177480  0.53135333  2.17538339 -0.56961772  0.21383861  0.52305069
#>  [55]  1.51011486  0.48288176  0.50322867  1.55441013  0.62107274  0.03289801
#>  [61]  1.30596390  1.28203479  0.93559990  0.77655385 -0.31092848  2.36944918
#>  [67]  1.98287367  1.40987161 -0.13560283 -0.20684955  0.47605104  1.30855065
#>  [73]  1.66809661  0.94652497 -0.51491989  1.64276393  2.81480863 -1.10838760
#>  [79] -0.11130911 -0.18462476  0.89527352 -1.01018336  1.99963243  1.68116337
#>  [85]  2.29545362  0.02711322  0.71887354  0.45310190  0.57046545  1.14708072
#>  [91]  1.95629000  1.46083973  2.32648018 -0.47370253  0.83816483  1.82841383
#>  [97]  0.17347158  2.01610174  1.39713221  0.49608864
#> 
#> 
#> Slot "options":
#> An object of class "McmcOptions"
#> Slot "iterations":
#> [1] 210
#> 
#> Slot "burnin":
#> [1] 10
#> 
#> Slot "step":
#> [1] 2
#> 
#> Slot "rng_kind":
#> [1] NA
#> 
#> Slot "rng_seed":
#> [1] NA
#> 
#>