Bayesian Hypothesis Testing

bayes_hypotheses.js

function Pmf(domain){
	this.domain = {}
  
  for(var i = 0; i < domain.length; i++){
  	value = domain[i][0];
    probability = domain[i][1];
    
  	this.domain[value] = probability;
  }
}

Pmf.prototype.normalize = function(){
	total = 0;
	keys = Object.keys(this.domain);

	for(var i = 0; i < keys.length; i++){
  	mass = this.domain[keys[i]];
    total += mass;
  }

  for(var i = 0; i < keys.length; i++){
  	this.domain[keys[i]] /= total;
  }
};

Pmf.prototype.print = function(id){
	inner_html = document.querySelector(id).innerHTML;
  keys = Object.keys(this.domain);
  
  for(var i = 0; i < keys.length; i++){
  	inner_html += keys[i] + ": " + Math.round(this.domain[keys[i]] * 100) / 100;
    inner_html += "<br/>";
  }
  
  document.querySelector(id).innerHTML = inner_html;
};

function Hypotheses(hypotheses, id){
	let this_hypotheses = new Pmf(hypotheses);
  this.hypotheses = this_hypotheses;
  this.hypotheses.normalize();
  this.id = id;
}

Hypotheses.prototype.print = function(){
	document.querySelector(this.id).innerHTML += "Hypthesis: Probability<br/>";
  this.hypotheses.print(this.id);
};

Hypotheses.prototype.update = function(datum){
	keys = Object.keys(this.hypotheses.domain);
  for(var i = 0; i < keys.length; i++){
  	likelihood = this.get_likelihood(keys[i], datum);
    this.hypotheses.domain[keys[i]] *= likelihood;
  }
  this.hypotheses.normalize();
};