In poissonconsulting/tmbr: Analyses Using TMB

knitr::opts_chunk$set(
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tmbr

Introduction

tmbr (pronounced timber) is an R package to facilitate analyses using Template Model Builder (TMB). It is part of the mbr family of packages.

Demonstration

library(magrittr)
library(ggplot2)
library(mbr)
library(tmbr)

model <- model("#include <TMB.hpp>

template<class Type>
Type objective_function<Type>::operator() () {

DATA_VECTOR(Pairs);
DATA_VECTOR(Year);
DATA_FACTOR(Annual);
DATA_INTEGER(nAnnual);

PARAMETER(alpha);
PARAMETER(beta1);
PARAMETER(beta2);
PARAMETER(beta3);
PARAMETER_VECTOR(bAnnual);
PARAMETER(log_sAnnual);

Type sAnnual = exp(log_sAnnual);

vector<Type> ePairs = Pairs;

Type nll = 0.0;

for(int i = 0; i < nAnnual; i++){
  nll -= dnorm(bAnnual(i), Type(0), sAnnual, true);
}

for(int i = 0; i < Pairs.size(); i++){
  ePairs(i) = exp(alpha + beta1 * Year(i) + beta2 * pow(Year(i), 2) + beta3 * pow(Year(i), 3) + bAnnual(Annual(i)));
  nll -= dpois(Pairs(i), ePairs(i), true);
}
ADREPORT(sAnnual)
return nll;
}")

# add R code to calculate derived parameters
model %<>% update_model(new_expr = "
for (i in 1:length(Pairs)) {
  log(prediction[i]) <- alpha + beta1 * Year[i] + beta2 * Year[i]^2 + beta3 * Year[i]^3 + bAnnual[Annual[i]]
}")

# define data types and center year
model %<>% update_model(
  gen_inits = function(data) list(alpha = 4, beta1 = 1, beta2 = 0, beta3 = 0, log_sAnnual = 0, bAnnual = rep(0, data$nAnnual)),
  select_data = list("Pairs" = integer(), "Year*" = integer(), Annual = factor()),
  random_effects = list(bAnnual = "Annual"))

data <- bauw::peregrine
data$Annual <- factor(data$Year)

analysis <- analyse(model, data = data)

coef(analysis)

year <- predict(analysis, new_data = "Year")

ggplot(data = year, aes(x = Year, y = estimate)) +
  geom_point(data = bauw::peregrine, aes(y = Pairs)) +
  geom_line() +
  expand_limits(y = 0)

Installation

To install from GitHub

install.packages("devtools")
devtools::install_github("poissonconsulting/tmbr")

Citation

citation(package = 'tmbr')

Contribution

Please report any issues.

Pull requests are always welcome.

Code of Conduct

Please note that the tmbr project is released with a Contributor Code of Conduct. By contributing to this project, you agree to abide by its terms.

poissonconsulting/tmbr documentation built on Oct. 3, 2023, 12:24 p.m.