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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] -2.340131855 -1.101269773 -1.166113717 -2.408639618  0.025387599
#>   [6]  0.383326868 -3.549434060 -0.331145396 -1.379215137 -0.955975125
#>  [11] -0.784898159 -1.253269187 -1.445455143 -0.815082619 -0.582551350
#>  [16] -3.336837735 -2.799487997  0.850082421 -1.337395945 -0.536545140
#>  [21]  0.303465825 -2.016517309 -2.050202142 -1.342355176 -1.916535664
#>  [26] -0.700983780 -0.843067324 -1.847374593 -1.321957554 -1.038221493
#>  [31] -0.311497267 -2.569897507 -0.991323738 -0.889499404  0.703523164
#>  [36] -1.167505994 -0.018742191 -1.242087093 -1.285426537 -1.630612379
#>  [41] -0.803889900 -1.065616006  0.467454981  0.465777451 -0.005154571
#>  [46] -2.488022418 -1.534366717 -1.777327686 -1.795710315 -1.009855866
#>  [51] -0.232552851 -0.201816969  0.029513937 -1.081178368 -1.098242691
#>  [56] -1.367581691 -3.193730735 -1.122425176 -2.033604033 -2.038209999
#>  [61] -0.371511634 -1.952157586 -1.285099319 -0.408026122  0.174499883
#>  [66] -1.843202171 -1.327465396 -0.112784449 -1.259452484 -1.137322961
#>  [71] -1.970894262 -0.684010378 -2.518420060 -1.933332082 -0.464202045
#>  [76] -0.661114484 -0.205251794 -1.738377749 -1.024072184 -0.563885686
#>  [81] -1.287187390  0.090299772 -1.913330282 -1.005827591 -2.420592555
#>  [86] -0.889120065 -2.146610106 -0.088631254 -0.701535529 -1.500497309
#>  [91] -0.132492199  1.268038963 -1.587332135 -1.498055505  0.262911457
#>  [96] -0.217729616  1.411819264 -0.685845274 -0.203796710  0.111649592
#> 
#> $alpha1
#>   [1]  1.01398841  1.56566128 -0.70237537  2.29234015 -0.53435720  1.71652381
#>   [7]  1.19530803  1.51547497  1.79866938  1.48153848  1.66616656  1.71483075
#>  [13]  2.41042114  1.55021500  0.17934873  2.58297580  2.98709153 -0.66868091
#>  [19]  2.19307827  1.56814853  1.28745685  1.04816322  2.73207674  0.85164066
#>  [25]  1.03611422  2.01264245  2.27095088  3.07471308 -0.49740236  1.29643463
#>  [31] -0.55420091  2.93383316  0.99886801  1.69949281 -0.49666672  0.20345308
#>  [37]  1.85829535  0.48500033 -0.50146935  2.73101717  1.28343722  0.82025186
#>  [43]  0.78736783  1.44383324  0.31418922  2.27750346  2.74722500  0.73282653
#>  [49]  0.64588078  0.81273916  0.07739871  0.91184640  1.02600750  2.77677847
#>  [55]  0.18166404  2.02227440  1.66960111  0.23255165  2.51727613  0.76073368
#>  [61]  3.00083691  0.55305830  0.95857150  1.39803487  0.93644781  1.35244504
#>  [67]  2.18225990 -1.12737965  1.76220336  1.59148503  3.23293586  1.70854891
#>  [73]  0.22922087  1.48910859  0.96334508  1.11322484  0.78179463  1.96134353
#>  [79] -0.99592652  2.09198325 -0.04713409  1.67449636  1.76566497  1.45598201
#>  [85]  1.02047017  0.69328814  1.19256669  0.63796497  0.33673949  0.38050675
#>  [91]  1.19062618 -1.73114647  2.11635031  2.16218417  0.56861246  0.31045862
#>  [97]  1.28056412 -0.06391553  1.33886636  0.82044731
#> 
#> 
#> 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
#> 
#>