Added Daniel's Bayes Net code. Converted example code to unit tests. Minor code clean-up.

This commit is contained in:
Woody Folsom
2012-03-11 10:33:45 -04:00
parent a021dc2fc0
commit 571d0a1922
27 changed files with 2310 additions and 0 deletions

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package dkohl.bayes.bayesnet;
import java.util.HashMap;
import java.util.LinkedList;
import dkohl.bayes.probability.Variable;
import dkohl.bayes.probability.distribution.ProbabilityDistribution;
/**
* Represents a Bayes net as a graph with a probability table associated with
* each node.
*
* @author Daniel Kohlsdorf
*/
public class BayesNet extends NamedGraph {
/**
* The probability tables for each node
*/
private HashMap<String, ProbabilityDistribution> nodes;
private LinkedList<Variable> variables;
public BayesNet(String names[]) {
super(names);
this.nodes = new HashMap<String, ProbabilityDistribution>();
this.variables = new LinkedList<Variable>();
}
public void setDistribution(Variable node, ProbabilityDistribution dist) {
nodes.put(node.getName(), dist);
variables.add(node);
}
public void updateDistribution(Variable node, ProbabilityDistribution dist) {
nodes.put(node.getName(), dist);
}
public HashMap<String, ProbabilityDistribution> getNodes() {
return nodes;
}
public LinkedList<Variable> getVariables() {
return variables;
}
}

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package dkohl.bayes.bayesnet;
import java.util.HashMap;
import java.util.LinkedList;
import com.google.common.base.Preconditions;
/**
* A Graph: G(V, E) implemented as a |V| x |V| matrix.
*
* Just one node type !!!!
*
* @author Daniel Kohlsdorf
*/
public class NamedGraph {
/**
* net[i][j]: variable i is connected to j.
*/
private boolean net[][];
/**
* Mapping variable names to positions in the graph's matrix.
*/
private HashMap<String, Integer> variable2pos;
/**
* Mapping positions in the graph to variable names.
*/
private HashMap<Integer, String> pos2variable;
/**
* Initializes the graph of size: |VariableNames| x |VariableNames|
*
* @param variableNames
* The names of the variables
*/
public NamedGraph(String variableNames[]) {
variable2pos = new HashMap<String, Integer>();
pos2variable = new HashMap<Integer, String>();
int num_nodes = variableNames.length;
net = new boolean[num_nodes][num_nodes];
for (int i = 0; i < num_nodes; i++) {
variable2pos.put(variableNames[i], i);
pos2variable.put(i, variableNames[i]);
for (int j = 0; j < num_nodes; j++) {
net[i][j] = false;
}
}
}
/**
* Connects two existing vertices in the graph.
*
* @param x
* the variable to connect
* @param y
* the parent (or other node for undirected graphs)
*/
public void connect(String x, String y) {
Preconditions.checkArgument(variable2pos.containsKey(x),
"Variable not known: " + x);
Preconditions.checkArgument(variable2pos.containsKey(y),
"Variable not known: " + y);
int variable_index = variable2pos.get(x);
int bias_index = variable2pos.get(y);
net[bias_index][variable_index] = true;
}
/**
* Returns the names of the variable's parents
*
* @param variable
* the target variable
* @return list of variable names
*/
public LinkedList<String> getParents(String variable) {
Preconditions.checkArgument(variable2pos.containsKey(variable),
"Variable not known: " + variable);
LinkedList<String> parents = new LinkedList<String>();
int variable_pos = variable2pos.get(variable);
for (int i = 0; i < net.length; i++) {
if (net[i][variable_pos]) {
String variableName = pos2variable.get(i);
parents.add(variableName);
}
}
return parents;
}
}

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package dkohl.bayes.estimation;
import java.util.LinkedList;
import com.google.common.base.Preconditions;
import dkohl.bayes.bayesnet.BayesNet;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
import dkohl.bayes.probability.Variable;
import dkohl.bayes.probability.distribution.ContinousDistribution;
import dkohl.bayes.probability.distribution.ProbabilityDistribution;
import dkohl.bayes.probability.distribution.ProbabilityTable;
import dkohl.bayes.probability.distribution.ProbabilityTree;
import dkohl.bayes.statistic.DataSet;
/**
* Works for fully observable bayes nets
*
* @author Daniel Kohlsdorf
*/
public class MaximumLikelihoodEstimation {
/**
* Enumerates all possible assignments for a set of variables using depth
* first + back tracking. Estimates the probability for each assignment
* given data and inserts the values in a probability function.
*
* @param target
* The target variable
* @param assignments
* A list built by traversing the tree. Adding an assignment on
* each layer
* @param variables
* All variables to assign
* @param current
* The current variable
* @param data
* the data for estimation
* @param table
* the probability table
*/
private static void enumerate(Assignment target,
LinkedList<Assignment> assignments, LinkedList<Variable> variables,
int current, DataSet data, ProbabilityDistribution dist) {
if (assignments.size() == variables.size()) {
if (dist instanceof ProbabilityTable) {
double likelihood = data.prob(target, assignments)
.getProbability();
assignments.add(target);
ProbabilityTable table = (ProbabilityTable) dist;
table.setProbabilityForAssignment(assignments, new Probability(
likelihood));
}
if (dist instanceof ProbabilityTree) {
double likelihood = data.prob(target, assignments)
.getProbability();
assignments.add(target);
ProbabilityTree tree = (ProbabilityTree) dist;
tree.setProbabilityForAssignment(assignments, new Probability(
likelihood));
}
if (dist instanceof ContinousDistribution) {
ContinousDistribution pdf = (ContinousDistribution) dist;
for (LinkedList<Assignment> assignment : data
.getAssignmentMatchesForQuery(assignments)) {
pdf.pushAssignment(assignment);
}
}
return;
}
Variable variable = variables.get(assignments.size());
for (String value : variable.getDomain()) {
LinkedList<Assignment> new_assignments = new LinkedList<Assignment>(
assignments);
new_assignments.add(new Assignment(variable, value));
enumerate(target, new_assignments, variables, current + 1, data,
dist);
}
}
public static void estimate(DataSet data, BayesNet net, String targetName) {
Variable target = null;
// Search parent variables
LinkedList<String> parentNames = net.getParents(targetName);
LinkedList<Variable> allVariables = net.getVariables();
LinkedList<Variable> parentVariables = new LinkedList<Variable>();
for (Variable variable : allVariables) {
if (parentNames.contains(variable.getName())) {
parentVariables.add(variable);
}
if (variable.getName().equals(targetName)) {
target = variable;
}
}
Preconditions.checkState(target != null, "MLE: variable " + targetName
+ "Not in net");
/**
* For all assignments of this variable list all assignments of it's
* parents and estimate the probability for each assignment using data.
*/
ProbabilityDistribution dist = net.getNodes().get(targetName);
if (dist instanceof ContinousDistribution) {
enumerate(null, new LinkedList<Assignment>(), parentVariables, 0,
data, dist);
} else {
for (String value : target.getDomain()) {
enumerate(new Assignment(target, value),
new LinkedList<Assignment>(), parentVariables, 0, data,
dist);
}
}
net.updateDistribution(target, dist);
}
}

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package dkohl.bayes.inference;
import java.util.LinkedList;
import java.util.List;
import dkohl.bayes.bayesnet.BayesNet;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.ProbabilityAssignment;
import dkohl.bayes.probability.Variable;
/**
* Enumeration Algorithm: Exact inference in Baysian Networks.
*
* @author Daniel Kohlsdorf
*
*/
public class EnumerateAll {
/**
* The probability distribution of a variable.
*
* @param query
* the variable
* @param net
* the bayes net defining the independence
* @param assignments
* a set of assignments in this net.
* @return
*/
public static LinkedList<ProbabilityAssignment> enumerateAsk(
Variable query, BayesNet net, LinkedList<Assignment> assignments) {
LinkedList<Variable> variables = net.getVariables();
LinkedList<ProbabilityAssignment> result = new LinkedList<ProbabilityAssignment>();
// Evaluate probability for each possible
// value of the variable by enumeration
for (String value : query.getDomain()) {
LinkedList<Assignment> temp = new LinkedList<Assignment>();
temp.addAll(assignments);
temp.add(new Assignment(query, value));
double prob = enumerateAll(net, variables, temp);
result.add(new ProbabilityAssignment(query, value, prob));
}
return result;
}
/**
* Decides if a variable is hidden or not. A variable is hidden if it is not
* assigned.
*
* @param variable
* the variable in question.
* @param assignments
* all the assignments
* @return true if not assigned
*/
private static boolean hidden(Variable variable,
LinkedList<Assignment> assignments) {
for (Assignment assignment : assignments) {
if (assignment.getVariable().getName().equals(variable.getName())) {
return false;
}
}
return true;
}
/**
* Recursively evaluate probability of an assignment.
*
* Can be seen as depth first search + backtracking (branching on hidden
* nodes)
*
* @param net
* a bayes net defining independence
* @param variables
* the variables left to evaluate
* @param assignments
* all assignments
* @return
*/
public static double enumerateAll(BayesNet net, List<Variable> variables,
LinkedList<Assignment> assignments) {
// if no variables left to evaluate,
// leaf node reached.
if (variables.isEmpty()) {
return 1;
}
// evaluate variable, recurse on rest
// PROLOG: [Variable|Rest].
Variable variable = variables.get(0);
List<Variable> rest = variables.subList(1, variables.size());
// if current variable is hidden
if (hidden(variable, assignments)) {
// sum out all possible values for that variable
double sumOut = 0;
for (String value : variable.getDomain()) {
// by temporarily adding each value to the asigned variable set
LinkedList<Assignment> temp = new LinkedList<Assignment>();
temp.addAll(assignments);
temp.add(new Assignment(variable, value));
// then evaluate this variable
double val = net.getNodes().get(variable.getName()).eval(temp)
.getProbability();
// and all that depend on it
val *= enumerateAll(net, rest, temp);
sumOut += val;
}
return sumOut;
}
// if not just evaluate variable and continue.
return net.getNodes().get(variable.getName()).eval(assignments)
.getProbability()
* enumerateAll(net, rest, assignments);
}
}

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package dkohl.bayes.probability;
/**
* An assigned variable
*
* @author Daniel Kohlsdorf
*/
public class Assignment {
public static final String NOT_ASSIGNED = "NOT_ASSIGNED";
/**
* The variable specifying the domain.
*/
private Variable variable;
/**
* The assigned value
*/
private String value;
public Assignment(Variable variable, String value) {
super();
this.variable = variable;
this.value = value;
}
/**
* Is this assignment a valid one given my domain?
*
* @return true if the assignment is valid
*/
public boolean valid() {
for (String outcome : variable.getDomain()) {
if (outcome.equals(value)) {
return true;
}
}
return false;
}
public Variable getVariable() {
return variable;
}
public void setVariable(Variable variable) {
this.variable = variable;
}
public String getValue() {
return value;
}
public void setValue(String value) {
this.value = value;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(variable);
sb.append(" = ");
sb.append(value);
return sb.toString();
}
}

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package dkohl.bayes.probability;
import com.google.common.base.Preconditions;
/**
* A probabilistic event
*
* @author Daniel Kohlsdorf
*/
public class Probability {
/**
* The probability for this event
*/
private double probability;
public Probability(double probability) {
setProbability(probability);
}
public double getProbability() {
return probability;
}
/**
* Sets this probability to a value p that holds:
*
* 0 >= p <= 1, p in R
*
* @param probability
*/
public void setProbability(double probability) {
Preconditions.checkArgument(probability <= 1,
"Probability Error: P >= 1: " + probability);
Preconditions.checkArgument(probability >= 0,
"Probability Error: P <= 0: " + probability);
this.probability = probability;
}
/**
* Returns the rest of the probability
*
* @return 1 - p
*/
public Probability rest() {
return new Probability(1 - probability);
}
}

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package dkohl.bayes.probability;
public class ProbabilityAssignment extends Assignment {
private double probability;
public ProbabilityAssignment(Variable variable, String value,
double probability) {
super(variable, value);
this.probability = probability;
}
public double getProbability() {
return probability;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("(");
sb.append(super.toString());
sb.append(") ");
sb.append(probability);
return sb.toString();
}
}

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package dkohl.bayes.probability;
/**
* A named variable with a domain of possible values it can take
*
* @author Daniel Kohlsdorf
*/
public class Variable {
/**
* The name of the variable
*/
private String name;
/**
* The domain of the variable
*/
private String domain[];
public Variable(String name, String[] domain) {
super();
this.name = name;
this.domain = domain;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String[] getDomain() {
return domain;
}
public void setDomain(String[] domain) {
this.domain = domain;
}
public int domainSize() {
return domain.length;
}
@Override
public String toString() {
return name;
}
}

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package dkohl.bayes.probability.distribution;
import java.util.HashMap;
import java.util.LinkedList;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
public class ContinousDistribution implements ProbabilityDistribution {
/**
* The involved variables mapping to row
*/
private HashMap<String, Integer> variable2row;
private HashMap<String, Gaussian> distribution;
private String name;
public ContinousDistribution(String names[], int self) {
distribution = new HashMap<String, Gaussian>();
this.variable2row = new HashMap<String, Integer>();
int count = 0;
for (int i = 0; i < names.length; i++) {
if (i != self) {
variable2row.put(names[i], count);
count++;
} else {
name = names[i];
}
}
}
/**
* Generates a table entry key for an assignment
*
* @param assignment
* the assignment
*
* @return the key
*/
public String generateKey(LinkedList<Assignment> assignment) {
String[] values = new String[variable2row.size()];
for (Assignment col : assignment) {
if (variable2row.containsKey(col.getVariable().getName())) {
int row = variable2row.get(col.getVariable().getName());
values[row] = col.getValue();
}
}
String key = "";
for (String entry : values) {
key += entry + ";";
}
return key;
}
public Assignment value(LinkedList<Assignment> assignment) {
for (Assignment a : assignment) {
if (a.getVariable().getName().equals(name)) {
return a;
}
}
return null;
}
@Override
public Probability eval(LinkedList<Assignment> assignment) {
String assignment_key = generateKey(assignment);
if (distribution.get(assignment_key) == null) {
return new Probability(0);
}
return new Probability(distribution.get(assignment_key).eval(
value(assignment)));
}
public void pushAssignment(LinkedList<Assignment> assignment) {
String key = generateKey(assignment);
Gaussian gaussian = new Gaussian();
if (distribution.containsKey(key)) {
gaussian = distribution.get(key);
}
gaussian.push(value(assignment));
distribution.put(key, gaussian);
}
public void estimate() {
for (String key : distribution.keySet()) {
distribution.get(key).estimate();
}
}
public String[] getNames() {
String[] names = new String[variable2row.size()];
for (String name : variable2row.keySet()) {
names[variable2row.get(name)] = name;
}
return names;
}
public HashMap<String, Gaussian> getAssignments() {
return distribution;
}
}

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package dkohl.bayes.probability.distribution;
import java.util.Vector;
import dkohl.bayes.probability.Assignment;
public class Gaussian {
public static final double TWO_PI = 2 * Math.PI;
private double mean;
private double var;
private Vector<Double> samples;
public Gaussian() {
samples = new Vector<Double>();
}
public void push(Assignment assignment) {
double sample = Double.valueOf(assignment.getValue());
samples.add(sample);
}
public void estimate() {
mean = 0;
for(Double sample : samples) {
mean += sample;
}
mean /= samples.size();
var = 0;
for(Double sample : samples) {
var += Math.pow(sample - mean, 2);
}
var /= samples.size();
}
public double eval(Assignment assignment) {
double sample = Double.valueOf(assignment.getValue());
double fac = 1 / (Math.sqrt(TWO_PI * var));
return fac * Math.exp(-0.5 * (Math.pow(sample - mean, 2) / var));
}
@Override
public String toString() {
return "< " + mean + ", " + Math.sqrt(var) + " >";
}
}

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package dkohl.bayes.probability.distribution;
import java.util.LinkedList;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
/**
* A probability distribution.
*
* @author Daniel Kohlsdorf
*/
public interface ProbabilityDistribution {
/**
* Returns probability given an assignments.
*
* @param assignment A set of assigned variables
* @return probability of that assignment
*/
public Probability eval(LinkedList<Assignment> assignment);
}

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package dkohl.bayes.probability.distribution;
import java.util.HashMap;
import java.util.LinkedList;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
/**
* A probability table defined as a table of all combinations of all possible
* values of the varibales involved.
*
* @author Daniel Kohlsdorf
*/
public class ProbabilityTable implements ProbabilityDistribution {
/**
* The involved variables mapping to row
*/
private HashMap<String, Integer> variable2row;
/**
* An P(assignment key) assignment_key var1_value....varN_value : String
*/
private HashMap<String, Probability> assignments;
public ProbabilityTable(String names[]) {
assignments = new HashMap<String, Probability>();
this.variable2row = new HashMap<String, Integer>();
for (int i = 0; i < names.length; i++) {
variable2row.put(names[i], i);
}
}
public ProbabilityTable(LinkedList<String> names) {
assignments = new HashMap<String, Probability>();
this.variable2row = new HashMap<String, Integer>();
for (int i = 0; i < names.size(); i++) {
variable2row.put(names.get(i), i);
System.out.println(names.get(i));
}
}
/**
* Sets the probability for a table entry key. You can generate one from
* your assignments using generateKey, or just use this same method with
* your assignments.
*
* @param key
* the entry key
* @param probability
* the associated probability
*/
public void setProbabilityForAssignment(String key, Probability probability) {
assignments.put(key, probability);
}
/**
* Sets the probability for the given assignment
*
* @param assignment
* the assignment
* @param probability
* the associated probability
*/
public void setProbabilityForAssignment(LinkedList<Assignment> assignment,
Probability probability) {
String key = generateKey(assignment);
assignments.put(key, probability);
}
@Override
public Probability eval(LinkedList<Assignment> assignment) {
String key = generateKey(assignment);
return assignments.get(key);
}
/**
* Generates a table entry key for an assignment
*
* @param assignment
* the assignment
*
* @return the key
*/
public String generateKey(LinkedList<Assignment> assignment) {
String[] values = new String[variable2row.size()];
for (Assignment col : assignment) {
if (variable2row.containsKey(col.getVariable().getName())) {
int row = variable2row.get(col.getVariable().getName());
values[row] = col.getValue();
}
}
String key = "";
for (String entry : values) {
key += entry + ";";
}
return key;
}
public HashMap<String, Probability> getAssignments() {
return assignments;
}
public String[] getNames() {
String[] names = new String[variable2row.size()];
for (String name : variable2row.keySet()) {
names[variable2row.get(name)] = name;
}
return names;
}
}

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package dkohl.bayes.probability.distribution;
import java.util.LinkedList;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
import dkohl.bayes.probability.distribution.tree.DecisionNode;
import dkohl.bayes.probability.distribution.tree.ProbabilityLeaf;
/**
* Probability distribution in descision tree representation
*
* DANGER: No node ordering during creation yet.
*
* @author Daniel Kohlsdorf
*/
public class ProbabilityTree implements ProbabilityDistribution {
/**
* The trees root node
*/
private DecisionNode root = null;
/**
* Initialize the tree
* by creating one path, along an assignment of
* variables and add a probability node at the end.
*
* @param assignment
* @param probability
*/
private void initTree(LinkedList<Assignment> assignment, Probability probability) {
root = new DecisionNode(assignment.get(0).getVariable().getName());
DecisionNode parent = root;
for(int i = 1; i < assignment.size(); i++) {
// add the child to the parent with the key of the parents assignment
DecisionNode child = new DecisionNode(assignment.get(i).getVariable().getName());
parent.put(assignment.get(i - 1).getValue(), child);
parent = child;
}
parent.put(assignment.getLast().getValue(), new ProbabilityLeaf(probability));
}
/**
* Follow existing paths until
* successors do not contain the current assignment,
* then start inserting.
*
* @param assignment
* @param probability
*/
public void setProbabilityForAssignment(LinkedList<Assignment> assignment, Probability probability) {
if(root == null) {
initTree(assignment, probability);
} else {
DecisionNode parent = root;
for(int i = 1; i < assignment.size(); i++) {
if(parent.getSuccessors().containsKey(assignment.get(i - 1).getValue())) {
parent = (DecisionNode) parent.getSuccessors().get(assignment.get(i - 1).getValue());
} else {
DecisionNode child = new DecisionNode(assignment.get(i).getVariable().getName());
parent.put(assignment.get(i - 1).getValue(), child);
parent = child;
}
}
parent.put(assignment.getLast().getValue(), new ProbabilityLeaf(probability));
}
}
@Override
public Probability eval(LinkedList<Assignment> assignment) {
return root.eval(assignment);
}
}

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package dkohl.bayes.probability.distribution.tree;
import java.util.HashMap;
import java.util.LinkedList;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
import dkohl.bayes.probability.distribution.ProbabilityDistribution;
/**
* Represents a random variable. Maps each outcome to a successor.
*
* @author Daniel Kohlsdorf
*/
public class DecisionNode implements ProbabilityDistribution {
/**
* The successors for each outcome
*/
private HashMap<String, ProbabilityDistribution> successors;
/**
* Name of the variable
*/
private String variable;
public DecisionNode(String variable) {
this.variable = variable;
successors = new HashMap<String, ProbabilityDistribution>();
}
public String getVariable() {
return variable;
}
public void put(String value, ProbabilityDistribution distribution) {
successors.put(value, distribution);
}
public HashMap<String, ProbabilityDistribution> getSuccessors() {
return successors;
}
@Override
public Probability eval(LinkedList<Assignment> assignment) {
// Evaluate recursively
for (Assignment a : assignment) {
if (a.getVariable().getName().equals(variable)) {
return successors.get(a.getValue()).eval(assignment);
}
}
try {
throw (new Exception("Domain Violation: " + variable));
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
}

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package dkohl.bayes.probability.distribution.tree;
import java.util.LinkedList;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
import dkohl.bayes.probability.distribution.ProbabilityDistribution;
/**
* Just a dummy node. Always returns the probability value, ignoring the
* assignment.
*
* @author Daniel Kohlsdorf
*/
public class ProbabilityLeaf implements ProbabilityDistribution {
private Probability probability;
public ProbabilityLeaf(Probability probability) {
super();
this.probability = probability;
}
@Override
public Probability eval(LinkedList<Assignment> assignment) {
return probability;
}
}

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package dkohl.bayes.statistic;
import java.util.HashMap;
import dkohl.bayes.probability.Assignment;
/**
* A data point or feature vector, that keeps observations.
*
* @author Daniel Kohlsdorf
*/
public class DataPoint extends HashMap<String, Assignment> {
private static final long serialVersionUID = 1L;
public DataPoint(DataPoint point) {
putAll(point);
}
public DataPoint() {
}
public void add(Assignment assignment) {
put(assignment.getVariable().getName(), assignment);
}
}

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package dkohl.bayes.statistic;
import java.util.LinkedList;
import java.util.Vector;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
/**
* A data set, defined as a vector of data points
*
* @author Daniel Kohlsdorf
*/
public class DataSet extends Vector<DataPoint> {
private static final long serialVersionUID = 1L;
public LinkedList<LinkedList<Assignment>> getAssignmentMatchesForQuery(
LinkedList<Assignment> given) {
LinkedList<LinkedList<Assignment>> assignments = new LinkedList<LinkedList<Assignment>>();
for (DataPoint point : this) {
boolean insert = true;
for (Assignment assignment : given) {
if (!match(point, assignment)) {
insert = false;
}
}
if (insert) {
assignments.add(new LinkedList<Assignment>(point.values()));
}
}
return assignments;
}
/**
* Is the assignment equal to a data point / observation ?
*
* @param point
* the point / observation
* @param query
* the assignment
* @return
*/
private boolean match(String queryName, DataPoint point,
LinkedList<Assignment> query) {
boolean queryFound = false;
for (Assignment assignment : query) {
if (!match(point, assignment)) {
return false;
}
if (point.containsKey(queryName)) {
queryFound = true;
}
}
if (!queryFound) {
return false;
}
return true;
}
private boolean match(DataPoint point, Assignment query) {
String name = query.getVariable().getName();
String value = query.getValue();
if (point.containsKey(name)) {
if (point.get(name).getValue().equals(value)) {
return true;
}
}
return false;
}
/**
* Estimating probability for: P(Query | given_1 .... given_N) = #(Query |
* given_1 .... given_N) / #(given_1 .... given_N)
*
* @param query
* @param given
* @return
*/
public Probability prob(Assignment query, LinkedList<Assignment> given) {
int matches = 0;
int num_query_given = 0;
for (DataPoint point : this) {
if (match(query.getVariable().getName(), point, given)) {
matches += 1;
if (match(point, query)) {
num_query_given += 1; // point.getWeight();
}
}
}
if (matches == 0) {
return new Probability(0);
}
return new Probability(num_query_given / ((double) matches));
}
}

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package dkohl.onthology;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Set;
import com.google.common.base.Preconditions;
public class Ontology {
/**
* Thing <- Class
*/
private HashMap<String, String> inheritance;
private HashMap<String, LinkedList<String>> classes2thing;
public Ontology(HashSet<String> classes) {
inheritance = new HashMap<String, String>();
this.classes2thing = new HashMap<String, LinkedList<String>>();
for (String key : classes) {
classes2thing.put(key, new LinkedList<String>());
}
}
public void define(String thing, String isA) {
Preconditions.checkArgument(classes2thing.containsKey(isA), "Class: "
+ isA + "notDefined");
LinkedList<String> things = classes2thing.get(isA);
things.add(thing);
classes2thing.put(isA, things);
inheritance.put(thing, isA);
}
public HashMap<String, String> getInheritance() {
return inheritance;
}
public HashMap<String, LinkedList<String>> getClasses2thing() {
return classes2thing;
}
public Set<String> getClasses() {
return classes2thing.keySet();
}
}

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package dkohl.bayes.example;
import static org.hamcrest.core.IsEqual.equalTo;
import static org.junit.Assert.assertThat;
import static org.junit.Assert.assertTrue;
import java.util.LinkedList;
import org.junit.Test;
import dkohl.bayes.bayesnet.BayesNet;
import dkohl.bayes.example.builders.AlarmNetBuilderTable;
import dkohl.bayes.example.builders.AlarmNetBuilderTree;
import dkohl.bayes.inference.EnumerateAll;
import dkohl.bayes.probability.ProbabilityAssignment;
import dkohl.bayes.probability.Variable;
public class AlarmExampleTest {
@Test
public void testAlarmExample() {
BayesNet sprinkler = AlarmNetBuilderTable.alarm();
sprinkler = AlarmNetBuilderTree.sprinkler();
// P(B | j, m)
LinkedList<ProbabilityAssignment> probs = EnumerateAll.enumerateAsk(
new Variable(AlarmNetBuilderTable.BURGLARY,
AlarmNetBuilderTable.DOMAIN), sprinkler,
AlarmNetBuilderTable.completeQueryBulgary());
System.out.print("Burglary: <");
for (ProbabilityAssignment p : probs) {
System.out.print("p: "+ p.toString() + ",");
}
System.out.println(">");
//assert that burglary is more likely to be false
assertThat(probs.size(),equalTo(2));
assertTrue(probs.get(0).getProbability() < probs.get(1).getProbability());
}
}

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package dkohl.bayes.example;
import java.util.LinkedList;
import static org.hamcrest.core.IsEqual.equalTo;
import static org.junit.Assert.assertThat;
import static org.junit.Assert.assertTrue;
import org.junit.Test;
import dkohl.bayes.bayesnet.BayesNet;
import dkohl.bayes.example.builders.FoodExampleBuilder;
import dkohl.bayes.inference.EnumerateAll;
import dkohl.bayes.probability.ProbabilityAssignment;
import dkohl.bayes.probability.Variable;
import dkohl.bayes.probability.distribution.ContinousDistribution;
import dkohl.bayes.probability.distribution.ProbabilityTable;
public class FoodExampleTest {
@Test
public void testFoodExample() {
BayesNet net = FoodExampleBuilder.dishNet();
System.out.println("VEGETRAIAN: ");
ProbabilityTable table = (ProbabilityTable) net.getNodes().get(
FoodExampleBuilder.SOMEONE_VEGETARIAN);
for (String name : table.getNames()) {
System.out.print(name + " ");
}
System.out.println();
for (String assignment : table.getAssignments().keySet()) {
System.out.println(assignment + " "
+ table.getAssignments().get(assignment).getProbability());
}
System.out.println("MEET: ");
table = (ProbabilityTable) net.getNodes().get(
FoodExampleBuilder.CONTAINS_MEET);
for (String name : table.getNames()) {
System.out.print(name + " ");
}
System.out.println();
for (String assignment : table.getAssignments().keySet()) {
System.out.println(assignment + " "
+ table.getAssignments().get(assignment).getProbability());
}
System.out.println("VEGETABLES: ");
table = (ProbabilityTable) net.getNodes().get(
FoodExampleBuilder.CONTAINS_VEGETABLE);
for (String name : table.getNames()) {
System.out.print(name + " ");
}
System.out.println();
for (String assignment : table.getAssignments().keySet()) {
System.out.println(assignment + " "
+ table.getAssignments().get(assignment).getProbability());
}
System.out.println("BEEF: ");
table = (ProbabilityTable) net.getNodes().get(
FoodExampleBuilder.CONTAINS_BEEF);
for (String name : table.getNames()) {
System.out.print(name + " ");
}
System.out.println();
for (String assignment : table.getAssignments().keySet()) {
System.out.println(assignment + " "
+ table.getAssignments().get(assignment).getProbability());
}
System.out.println("PORK: ");
table = (ProbabilityTable) net.getNodes().get(
FoodExampleBuilder.CONTAINS_PORK);
for (String name : table.getNames()) {
System.out.print(name + " ");
}
System.out.println();
for (String assignment : table.getAssignments().keySet()) {
System.out.println(assignment + " "
+ table.getAssignments().get(assignment).getProbability());
}
System.out.println("POTATOS: ");
table = (ProbabilityTable) net.getNodes().get(
FoodExampleBuilder.CONTAINS_POTATOS);
for (String name : table.getNames()) {
System.out.print(name + " ");
}
System.out.println();
for (String assignment : table.getAssignments().keySet()) {
System.out.println(assignment + " "
+ table.getAssignments().get(assignment).getProbability());
}
System.out.println("TOMATOS: ");
table = (ProbabilityTable) net.getNodes().get(
FoodExampleBuilder.CONTAINS_TOMATOS);
for (String name : table.getNames()) {
System.out.print(name + " ");
}
System.out.println();
for (String assignment : table.getAssignments().keySet()) {
System.out.println(assignment + " "
+ table.getAssignments().get(assignment).getProbability());
}
System.out.println("TASTE: ");
ContinousDistribution dist = (ContinousDistribution) net.getNodes()
.get(FoodExampleBuilder.TASTE);
for (String name : dist.getNames()) {
System.out.print(name + " ");
}
System.out.println();
for (String assignment : dist.getAssignments().keySet()) {
System.out.println(assignment + " "
+ dist.getAssignments().get(assignment));
}
LinkedList<ProbabilityAssignment> probs = EnumerateAll.enumerateAsk(
new Variable(FoodExampleBuilder.TASTE,
FoodExampleBuilder.RATING_DOMAIN), net,
FoodExampleBuilder.completeQueryTasteBeef());
double max_val = 0;
String max_arg = null;
for (ProbabilityAssignment p : probs) {
if (p.getProbability() > max_val) {
max_val = p.getProbability();
max_arg = p.getValue();
}
}
System.out.println("TASE BEEF: " + max_arg + " " + max_val);
probs = EnumerateAll.enumerateAsk(new Variable(
FoodExampleBuilder.TASTE, FoodExampleBuilder.RATING_DOMAIN),
net, FoodExampleBuilder.completeQueryTastePork());
max_val = 0;
max_arg = null;
for (ProbabilityAssignment p : probs) {
if (p.getProbability() > max_val) {
max_val = p.getProbability();
max_arg = p.getValue();
}
}
System.out.println("TASE PORK: " + max_arg + " " + max_val);
assertThat(max_arg, equalTo("10"));
assertTrue("Error: max_val for TASTE_PORK should be > 2.6%", max_val > 0.026);
}
}

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package dkohl.bayes.example;
import org.junit.Test;
import static org.hamcrest.core.IsEqual.equalTo;
import static org.junit.Assert.assertThat;
import dkohl.bayes.bayesnet.BayesNet;
import dkohl.bayes.estimation.MaximumLikelihoodEstimation;
import dkohl.bayes.example.builders.EstimateSprinklerNetBuilderTable;
import dkohl.bayes.probability.distribution.ProbabilityTable;
import dkohl.bayes.statistic.DataSet;
/**
* Parameter estimation for the sprinkler net example
*
* http://www.cs.ubc.ca/~murphyk/Bayes/bnintro.html
*
* @author Daniel Kohlsdorf
*/
public class SprinklerNetExampleTest {
@Test
public void testSprinklerNetExample() {
BayesNet net = EstimateSprinklerNetBuilderTable.sprinkler();
DataSet data = EstimateSprinklerNetBuilderTable.dataSet();
MaximumLikelihoodEstimation.estimate(data, net,
EstimateSprinklerNetBuilderTable.GRASS_WET);
/**
* Output PDF for grass is wet
*/
ProbabilityTable table = (ProbabilityTable) net.getNodes().get(
EstimateSprinklerNetBuilderTable.GRASS_WET);
for (String name : table.getNames()) {
System.out.print(name + " | ");
}
System.out.println();
for (String key : table.getAssignments().keySet()) {
System.out.println(key + " "
+ table.getAssignments().get(key).getProbability());
if ("false;false;true;".equals(key)) {
assertThat(table.getAssignments().get(key).getProbability(), equalTo(0.0));
}
if ("true;false;true;".equals(key)) {
assertThat(table.getAssignments().get(key).getProbability(), equalTo(0.9));
}
}
}
}

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package dkohl.bayes.example.builders;
import java.util.LinkedList;
import dkohl.bayes.bayesnet.BayesNet;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
import dkohl.bayes.probability.Variable;
import dkohl.bayes.probability.distribution.ProbabilityTable;
/**
* The alarm example for baysian nets.
*
* Stuart Russel, Peter Norvig: Artificial Intelligence: A Modern Approach, 3ed
* Edition, Prentice Hall, 2010
*
* @author Daniel Kohlsdorf
*/
public class AlarmNetBuilderTable {
// Variable names
public static final String BURGLARY = "Burglary";
public static final String EARTHQUAKE = "Earthquake";
public static final String ALARM = "Alarm";
public static final String JOHN = "John";
public static final String MARRY = "Marry";
// Possible outcomes
public static final String TRUE = "true";
public static final String FALSE = "false";
// A variables domain
public static final String DOMAIN[] = { TRUE, FALSE };
// A set of variables
public static final String VARIABLES[] = { BURGLARY, EARTHQUAKE, ALARM,
JOHN, MARRY };
/**
* Builds the query from the book: P(B| j, m)
*/
public static LinkedList<Assignment> completeQueryBulgary() {
LinkedList<Assignment> assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(JOHN, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(MARRY, DOMAIN), TRUE));
return new LinkedList<Assignment>(assignment);
}
/**
* Build burglary prior
*
* @param alarmNet
*/
private static void burglary(BayesNet alarmNet) {
Probability p_bulglary = new Probability(0.001);
String names[] = { BURGLARY };
ProbabilityTable burglary = new ProbabilityTable(names);
burglary.setProbabilityForAssignment("true;", p_bulglary);
burglary.setProbabilityForAssignment("false;", p_bulglary.rest());
alarmNet.setDistribution(new Variable(BURGLARY, DOMAIN), burglary);
}
/**
* Build earthquake prior
*
* @param alarmNet
*/
private static void earthquake(BayesNet alarmNet) {
Probability p_earthquake = new Probability(0.002);
String names[] = { EARTHQUAKE };
ProbabilityTable earthquake = new ProbabilityTable(names);
earthquake.setProbabilityForAssignment("true;", p_earthquake);
earthquake.setProbabilityForAssignment("false;", p_earthquake.rest());
alarmNet.setDistribution(new Variable(EARTHQUAKE, DOMAIN), earthquake);
}
/**
* Jhon calls!
*
* @param alarmNet
*/
private static void jhon(BayesNet alarmNet) {
// P(ALARM) == true
Probability t = new Probability(.90);
// P(ALARM) == false
Probability f = new Probability(.05);
String names[] = { ALARM, JOHN };
ProbabilityTable jhon = new ProbabilityTable(names);
jhon.setProbabilityForAssignment("true;true;", t);
jhon.setProbabilityForAssignment("false;true;", f);
jhon.setProbabilityForAssignment("true;false", t.rest());
jhon.setProbabilityForAssignment("false;false;", f.rest());
alarmNet.setDistribution(new Variable(JOHN, DOMAIN), jhon);
}
/**
* Marry calls!
*
* @param alarmNet
*/
private static void mary(BayesNet alarmNet) {
// P(ALARM) == true
Probability t = new Probability(.70);
// P(ALARM) == false
Probability f = new Probability(.01);
String names[] = { ALARM, MARRY };
ProbabilityTable marry = new ProbabilityTable(names);
marry.setProbabilityForAssignment("true;true;", t);
marry.setProbabilityForAssignment("false;true;", f);
marry.setProbabilityForAssignment("true;false", t.rest());
marry.setProbabilityForAssignment("false;false;", f.rest());
alarmNet.setDistribution(new Variable(MARRY, DOMAIN), marry);
}
/**
* The alarm goes off!
*
* @param alarmNet
*/
private static void alarm(BayesNet alarmNet) {
// P(ALARM | BURGLARY = true, EARTHQUAKE = true)
Probability tt = new Probability(.95);
// P(ALARM | BURGLARY = true, EARTHQUAKE = false)
Probability tf = new Probability(.94);
// P(ALARM | BURGLARY = false, EARTHQUAKE = true)
Probability ft = new Probability(.29);
// P(ALARM | BURGLARY = false, EARTHQUAKE = false)
Probability ff = new Probability(.001);
String names[] = { BURGLARY, EARTHQUAKE, ALARM };
ProbabilityTable alarm = new ProbabilityTable(names);
alarm.setProbabilityForAssignment(TRUE + ";" + TRUE + ";" + TRUE + ";",
tt);
alarm.setProbabilityForAssignment(
TRUE + ";" + FALSE + ";" + TRUE + ";", tf);
alarm.setProbabilityForAssignment(
FALSE + ";" + TRUE + ";" + TRUE + ";", ft);
alarm.setProbabilityForAssignment(FALSE + ";" + FALSE + ";" + TRUE
+ ";", ff);
alarm.setProbabilityForAssignment(
TRUE + ";" + TRUE + ";" + FALSE + ";", tt.rest());
alarm.setProbabilityForAssignment(TRUE + ";" + FALSE + ";" + FALSE
+ ";", tf.rest());
alarm.setProbabilityForAssignment(FALSE + ";" + TRUE + ";" + FALSE
+ ";", ft.rest());
alarm.setProbabilityForAssignment(FALSE + ";" + FALSE + ";" + FALSE
+ ";", ff.rest());
alarmNet.setDistribution(new Variable(ALARM, DOMAIN), alarm);
}
public static BayesNet alarm() {
BayesNet alarmNet = new BayesNet(VARIABLES);
// set probability tables and priors
burglary(alarmNet);
earthquake(alarmNet);
alarm(alarmNet);
jhon(alarmNet);
mary(alarmNet);
// construct the graph
alarmNet.connect(ALARM, BURGLARY);
alarmNet.connect(ALARM, EARTHQUAKE);
alarmNet.connect(JOHN, ALARM);
alarmNet.connect(MARRY, ALARM);
return alarmNet;
}
}

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package dkohl.bayes.example.builders;
import java.util.LinkedList;
import dkohl.bayes.bayesnet.BayesNet;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
import dkohl.bayes.probability.Variable;
import dkohl.bayes.probability.distribution.ProbabilityTree;
public class AlarmNetBuilderTree {
// Variable names
public static final String BURGLARY = "Burglary";
public static final String EARTHQUAKE = "Earthquake";
public static final String ALARM = "Alarm";
public static final String JOHN = "John";
public static final String MARRY = "Marry";
// Possible outcomes
public static final String TRUE = "true";
public static final String FALSE = "false";
// A variables domain
public static final String DOMAIN[] = { TRUE, FALSE };
// A set of variables
public static final String VARIABLES[] = { BURGLARY, EARTHQUAKE, ALARM,
JOHN, MARRY };
/**
* Builds the query from the book: P(B| j, m)
*/
public static LinkedList<Assignment> completeQueryBulgary() {
LinkedList<Assignment> assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(JOHN, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(MARRY, DOMAIN), TRUE));
return new LinkedList<Assignment>(assignment);
}
/**
* Build burglary prior
*
* @param sprinklerNet
*/
private static void burglary(BayesNet sprinklerNet) {
Probability p_bulglary = new Probability(0.001);
ProbabilityTree burglary = new ProbabilityTree();
LinkedList<Assignment> assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(BURGLARY, DOMAIN), TRUE));
burglary.setProbabilityForAssignment(assignment, p_bulglary);
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(BURGLARY, DOMAIN), FALSE));
burglary.setProbabilityForAssignment(assignment, p_bulglary.rest());
sprinklerNet.setDistribution(new Variable(BURGLARY, DOMAIN), burglary);
}
/**
* Build earthquake prior
*
* @param sprinklerNet
*/
private static void earthquake(BayesNet sprinklerNet) {
Probability p_earthquake = new Probability(0.002);
ProbabilityTree earthquake = new ProbabilityTree();
LinkedList<Assignment> assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(EARTHQUAKE, DOMAIN), TRUE));
earthquake.setProbabilityForAssignment(assignment, p_earthquake);
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(EARTHQUAKE, DOMAIN), FALSE));
earthquake.setProbabilityForAssignment(assignment, p_earthquake.rest());
sprinklerNet.setDistribution(new Variable(EARTHQUAKE, DOMAIN),
earthquake);
}
/**
* Jhon calls!
*
* @param sprinklerNet
*/
private static void jhon(BayesNet sprinklerNet) {
// P(ALARM) == true
Probability t = new Probability(.90);
// P(ALARM) == false
Probability f = new Probability(.05);
ProbabilityTree jhon = new ProbabilityTree();
LinkedList<Assignment> assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(JOHN, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), TRUE));
jhon.setProbabilityForAssignment(assignment, t);
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(JOHN, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), FALSE));
jhon.setProbabilityForAssignment(assignment, f);
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(JOHN, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), TRUE));
jhon.setProbabilityForAssignment(assignment, t.rest());
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(JOHN, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), FALSE));
jhon.setProbabilityForAssignment(assignment, f.rest());
sprinklerNet.setDistribution(new Variable(JOHN, DOMAIN), jhon);
}
/**
* Marry calls!
*
* @param sprinklerNet
*/
private static void mary(BayesNet sprinklerNet) {
// P(ALARM) == true
Probability t = new Probability(.70);
// P(ALARM) == false
Probability f = new Probability(.01);
ProbabilityTree mary = new ProbabilityTree();
LinkedList<Assignment> assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(MARRY, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), TRUE));
mary.setProbabilityForAssignment(assignment, t);
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(MARRY, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), FALSE));
mary.setProbabilityForAssignment(assignment, f);
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(MARRY, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), TRUE));
mary.setProbabilityForAssignment(assignment, t.rest());
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(MARRY, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), FALSE));
mary.setProbabilityForAssignment(assignment, f.rest());
sprinklerNet.setDistribution(new Variable(MARRY, DOMAIN), mary);
}
/**
* The alarm goes off!
*
* @param sprinklerNet
*/
private static void alarm(BayesNet sprinklerNet) {
// P(ALARM | BURGLARY = true, EARTHQUAKE = true)
Probability tt = new Probability(.95);
// P(ALARM | BURGLARY = true, EARTHQUAKE = false)
Probability tf = new Probability(.94);
// P(ALARM | BURGLARY = false, EARTHQUAKE = true)
Probability ft = new Probability(.29);
// P(ALARM | BURGLARY = false, EARTHQUAKE = false)
Probability ff = new Probability(.001);
ProbabilityTree alarm = new ProbabilityTree();
LinkedList<Assignment> assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(BURGLARY, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(EARTHQUAKE, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), TRUE));
alarm.setProbabilityForAssignment(assignment, tt);
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(BURGLARY, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(EARTHQUAKE, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), TRUE));
alarm.setProbabilityForAssignment(assignment, tf);
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(BURGLARY, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(EARTHQUAKE, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), TRUE));
alarm.setProbabilityForAssignment(assignment, ft);
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(BURGLARY, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(EARTHQUAKE, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), TRUE));
alarm.setProbabilityForAssignment(assignment, ff);
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(BURGLARY, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(EARTHQUAKE, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), FALSE));
alarm.setProbabilityForAssignment(assignment, tt.rest());
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(BURGLARY, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(EARTHQUAKE, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), FALSE));
alarm.setProbabilityForAssignment(assignment, tf.rest());
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(BURGLARY, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(EARTHQUAKE, DOMAIN), TRUE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), FALSE));
alarm.setProbabilityForAssignment(assignment, ft.rest());
assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(BURGLARY, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(EARTHQUAKE, DOMAIN), FALSE));
assignment.add(new Assignment(new Variable(ALARM, DOMAIN), FALSE));
alarm.setProbabilityForAssignment(assignment, ff.rest());
sprinklerNet.setDistribution(new Variable(ALARM, DOMAIN), alarm);
}
public static BayesNet sprinkler() {
BayesNet sprinklerNet = new BayesNet(VARIABLES);
// set probability tables and priors
burglary(sprinklerNet);
earthquake(sprinklerNet);
alarm(sprinklerNet);
jhon(sprinklerNet);
mary(sprinklerNet);
// construct the graph
sprinklerNet.connect(ALARM, BURGLARY);
sprinklerNet.connect(ALARM, EARTHQUAKE);
sprinklerNet.connect(JOHN, ALARM);
sprinklerNet.connect(MARRY, ALARM);
return sprinklerNet;
}
}

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@@ -0,0 +1,179 @@
package dkohl.bayes.example.builders;
import dkohl.bayes.bayesnet.BayesNet;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
import dkohl.bayes.probability.Variable;
import dkohl.bayes.probability.distribution.ProbabilityTable;
import dkohl.bayes.statistic.DataPoint;
import dkohl.bayes.statistic.DataSet;
/**
* The Sprinkler net example
*
* http://www.cs.ubc.ca/~murphyk/Bayes/bnintro.html
*
* @author Daniel Kohlsdorf
*/
public class EstimateSprinklerNetBuilderTable {
// Variable names
public static final String CLOUDY = "Cloudy";
public static final String SPRINKLER = "Sprinkler";
public static final String GRASS_WET = "GrassWet";
public static final String RAIN = "Rain";
// Possible outcomes
public static final String TRUE = "true";
public static final String FALSE = "false";
// A variables domain
public static final String DOMAIN[] = { TRUE, FALSE };
// A set of variables
public static final String VARIABLES[] = { CLOUDY, SPRINKLER, GRASS_WET,
RAIN };
private static void cloudy(BayesNet sprinklerNet) {
Probability p_cloudy = new Probability(0.5);
String names[] = { CLOUDY };
ProbabilityTable cloudy = new ProbabilityTable(names);
cloudy.setProbabilityForAssignment("true;", p_cloudy);
cloudy.setProbabilityForAssignment("false;", p_cloudy.rest());
sprinklerNet.setDistribution(new Variable(CLOUDY, DOMAIN), cloudy);
}
private static void rain(BayesNet sprinklerNet) {
Probability p_cloudy = new Probability(0.8);
Probability p_notcloudy = new Probability(0.2);
String names[] = { CLOUDY, RAIN };
ProbabilityTable rain = new ProbabilityTable(names);
rain.setProbabilityForAssignment("true;true;", p_cloudy);
rain.setProbabilityForAssignment("false;false;", p_notcloudy);
rain.setProbabilityForAssignment("false;true;", p_notcloudy.rest());
rain.setProbabilityForAssignment("true;false;", p_cloudy.rest());
sprinklerNet.setDistribution(new Variable(RAIN, DOMAIN), rain);
}
private static void sprinkler(BayesNet sprinklerNet) {
Probability p_cloudy = new Probability(0.1);
Probability p_notcloudy = new Probability(0.5);
String names[] = { CLOUDY, SPRINKLER };
ProbabilityTable sprinkler = new ProbabilityTable(names);
sprinkler.setProbabilityForAssignment("true;true;", p_cloudy);
sprinkler.setProbabilityForAssignment("false;false;", p_notcloudy);
sprinkler
.setProbabilityForAssignment("false;true;", p_notcloudy.rest());
sprinkler.setProbabilityForAssignment("true;false;", p_cloudy.rest());
sprinklerNet
.setDistribution(new Variable(SPRINKLER, DOMAIN), sprinkler);
}
private static void grass(BayesNet sprinklerNet) {
String names[] = { RAIN, SPRINKLER, GRASS_WET };
ProbabilityTable sprinkler = new ProbabilityTable(names);
sprinklerNet
.setDistribution(new Variable(GRASS_WET, DOMAIN), sprinkler);
}
public static BayesNet sprinkler() {
BayesNet sprinkler = new BayesNet(VARIABLES);
cloudy(sprinkler);
rain(sprinkler);
sprinkler(sprinkler);
grass(sprinkler);
sprinkler.connect(RAIN, CLOUDY);
sprinkler.connect(SPRINKLER, CLOUDY);
sprinkler.connect(GRASS_WET, RAIN);
sprinkler.connect(GRASS_WET, SPRINKLER);
return sprinkler;
}
private static Assignment build(String varible, String value) {
return new Assignment(new Variable(varible, DOMAIN), value);
}
public static DataSet dataSet() {
DataSet dataSet = new DataSet();
/**
* If rain is false and sprinkler is false, grass is never wet.
*/
DataPoint one = new DataPoint();
one.add(build(RAIN, FALSE));
one.add(build(SPRINKLER, FALSE));
one.add(build(GRASS_WET, FALSE));
dataSet.add(one);
/**
* 1 / 10 times the grass is not wet when the sprinkler is on
*/
DataPoint two = new DataPoint();
two.add(build(RAIN, FALSE));
two.add(build(SPRINKLER, TRUE));
two.add(build(GRASS_WET, FALSE));
dataSet.add(two);
/**
* 9 / 10 times the sprinkler is on and the grass is wet
*/
for (int i = 0; i < 9; i++) {
DataPoint point = new DataPoint();
point.add(build(RAIN, FALSE));
point.add(build(SPRINKLER, TRUE));
point.add(build(GRASS_WET, TRUE));
dataSet.add(point);
}
/**
* 1 / 10 times the grass is not wet when it rains
*/
DataPoint three = new DataPoint();
three.add(build(RAIN, TRUE));
three.add(build(SPRINKLER, FALSE));
three.add(build(GRASS_WET, FALSE));
dataSet.add(three);
/**
* 9 / 10 times it rains and the grass is wet
*/
for (int i = 0; i < 9; i++) {
DataPoint point = new DataPoint();
point.add(build(RAIN, TRUE));
point.add(build(SPRINKLER, FALSE));
point.add(build(GRASS_WET, TRUE));
dataSet.add(point);
}
/**
* 1 / 100 times the grass is not wet when it rains and the sprinkler is
* on
*/
DataPoint four = new DataPoint();
four.add(build(RAIN, TRUE));
four.add(build(SPRINKLER, TRUE));
four.add(build(GRASS_WET, FALSE));
dataSet.add(four);
/**
* 99 / 100 times it rains and the grass is wet
*/
for (int i = 0; i < 99; i++) {
DataPoint point = new DataPoint();
point.add(build(RAIN, TRUE));
point.add(build(SPRINKLER, TRUE));
point.add(build(GRASS_WET, TRUE));
dataSet.add(point);
}
return dataSet;
}
}

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@@ -0,0 +1,266 @@
package dkohl.bayes.example.builders;
import java.util.HashSet;
import java.util.LinkedList;
import dkohl.bayes.bayesnet.BayesNet;
import dkohl.bayes.estimation.MaximumLikelihoodEstimation;
import dkohl.bayes.probability.Assignment;
import dkohl.bayes.probability.Probability;
import dkohl.bayes.probability.Variable;
import dkohl.bayes.probability.distribution.ContinousDistribution;
import dkohl.bayes.probability.distribution.ProbabilityDistribution;
import dkohl.bayes.probability.distribution.ProbabilityTable;
import dkohl.bayes.statistic.DataPoint;
import dkohl.bayes.statistic.DataSet;
import dkohl.onthology.Ontology;
public class FoodExampleBuilder {
public static final String TASTE = "Taste";
public static final String SOMEONE_VEGETARIAN = "Vegetarian";
public static final String CONTAINS_MEET = "Meet";
public static final String CONTAINS_VEGETABLE = "Vegetable";
public static final String CONTAINS_BEEF = "Beef";
public static final String CONTAINS_PORK = "Pork";
public static final String CONTAINS_TOMATOS = "Tomatos";
public static final String CONTAINS_POTATOS = "Potatos";
public static final String TRUE_VALUE = "true";
public static final String FALSE_VALUE = "false";
public static final String DOMAIN[] = { TRUE_VALUE, FALSE_VALUE };
public static final String RATING_DOMAIN[] = { "1", "2", "3", "4", "5",
"6", "7", "8", "9", "10" };
private static final String[] VARIABLES = { SOMEONE_VEGETARIAN,
CONTAINS_BEEF, CONTAINS_MEET, CONTAINS_PORK, CONTAINS_POTATOS,
CONTAINS_TOMATOS, CONTAINS_VEGETABLE, TASTE };
private static final String[] OBSERVED = { CONTAINS_BEEF, CONTAINS_PORK,
CONTAINS_POTATOS, CONTAINS_TOMATOS, };
public static LinkedList<Assignment> completeQueryTasteBeef() {
LinkedList<Assignment> assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(CONTAINS_BEEF, DOMAIN),
TRUE_VALUE));
assignment.add(new Assignment(new Variable(CONTAINS_TOMATOS, DOMAIN),
TRUE_VALUE));
return new LinkedList<Assignment>(assignment);
}
public static LinkedList<Assignment> completeQueryTastePork() {
LinkedList<Assignment> assignment = new LinkedList<Assignment>();
assignment.add(new Assignment(new Variable(CONTAINS_PORK, DOMAIN),
TRUE_VALUE));
assignment.add(new Assignment(new Variable(CONTAINS_POTATOS, DOMAIN),
TRUE_VALUE));
return new LinkedList<Assignment>(assignment);
}
public static Ontology onto() {
HashSet<String> classes = new HashSet<String>();
classes.add(CONTAINS_MEET);
classes.add(CONTAINS_VEGETABLE);
Ontology onthology = new Ontology(classes);
onthology.define(CONTAINS_PORK, CONTAINS_MEET);
onthology.define(CONTAINS_BEEF, CONTAINS_MEET);
onthology.define(CONTAINS_TOMATOS, CONTAINS_VEGETABLE);
onthology.define(CONTAINS_POTATOS, CONTAINS_VEGETABLE);
return onthology;
}
private static Assignment build(String varible, String value) {
return new Assignment(new Variable(varible, DOMAIN), value);
}
public static DataPoint beefPotatoDish(int weight) {
DataPoint point = new DataPoint();
point.add(build(CONTAINS_BEEF, TRUE_VALUE));
point.add(build(CONTAINS_POTATOS, TRUE_VALUE));
point.add(build(TASTE, "" + weight));
return point;
}
public static DataPoint beefTomatoDish(int weight) {
DataPoint point = new DataPoint();
point.add(build(CONTAINS_BEEF, TRUE_VALUE));
point.add(build(CONTAINS_TOMATOS, TRUE_VALUE));
point.add(build(TASTE, "" + weight));
return point;
}
public static DataPoint porkBeefDish(int weight) {
DataPoint point = new DataPoint();
point.add(build(CONTAINS_BEEF, TRUE_VALUE));
point.add(build(CONTAINS_PORK, TRUE_VALUE));
point.add(build(TASTE, "" + weight));
return point;
}
public static DataPoint porkPotatoDish(int weight) {
DataPoint point = new DataPoint();
point.add(build(CONTAINS_PORK, TRUE_VALUE));
point.add(build(CONTAINS_POTATOS, TRUE_VALUE));
point.add(build(TASTE, "" + weight));
return point;
}
public static DataPoint porkTomatoDish(int weight) {
DataPoint point = new DataPoint();
point.add(build(CONTAINS_PORK, TRUE_VALUE));
point.add(build(CONTAINS_TOMATOS, TRUE_VALUE));
point.add(build(TASTE, "" + weight));
return point;
}
public static DataPoint potatoTomato(int weight) {
DataPoint point = new DataPoint();
point.add(build(CONTAINS_POTATOS, TRUE_VALUE));
point.add(build(CONTAINS_TOMATOS, TRUE_VALUE));
point.add(build(TASTE, "" + weight));
return point;
}
public static DataPoint normalize(DataPoint point, Ontology onto) {
// resolve onthology
DataPoint normPoint = new DataPoint(point);
for (String key : point.keySet()) {
if (onto.getInheritance().containsKey(key)) {
normPoint
.add(build(onto.getInheritance().get(key), TRUE_VALUE));
}
}
// implement closed world assumption
// everything unknown is false
for (String variable : VARIABLES) {
if (!normPoint.containsKey(variable)) {
normPoint.add(build(variable, FALSE_VALUE));
}
}
return normPoint;
}
public static DataSet examples() {
DataSet data = new DataSet();
Ontology onto = onto();
// user one ratings
data.add(normalize(porkTomatoDish(10), onto));
data.add(normalize(porkPotatoDish(9), onto));
data.add(normalize(beefTomatoDish(3), onto));
data.add(normalize(beefPotatoDish(0), onto));
data.add(normalize(potatoTomato(0), onto));
data.add(normalize(porkBeefDish(0), onto));
// user two ratings
data.add(normalize(porkTomatoDish(10), onto));
data.add(normalize(porkTomatoDish(8), onto));
data.add(normalize(porkPotatoDish(10), onto));
data.add(normalize(beefTomatoDish(0), onto));
data.add(normalize(beefPotatoDish(1), onto));
data.add(normalize(potatoTomato(7), onto));
data.add(normalize(porkBeefDish(10), onto));
// user three ratings
data.add(normalize(porkTomatoDish(10), onto));
data.add(normalize(porkPotatoDish(10), onto));
data.add(normalize(beefTomatoDish(3), onto));
data.add(normalize(beefPotatoDish(3), onto));
data.add(normalize(potatoTomato(3), onto));
data.add(normalize(porkBeefDish(4), onto));
return data;
}
public static ProbabilityDistribution vegi() {
String names[] = { SOMEONE_VEGETARIAN };
ProbabilityTable table = new ProbabilityTable(names);
table.setProbabilityForAssignment("true;", new Probability(0));
table.setProbabilityForAssignment("false;", new Probability(1));
return table;
}
public static ProbabilityDistribution beef() {
String names[] = { CONTAINS_MEET, CONTAINS_BEEF };
ProbabilityTable table = new ProbabilityTable(names);
return table;
}
public static ProbabilityDistribution pork() {
String names[] = { CONTAINS_MEET, CONTAINS_PORK };
ProbabilityTable table = new ProbabilityTable(names);
return table;
}
public static ProbabilityDistribution meet() {
String names[] = { SOMEONE_VEGETARIAN, CONTAINS_MEET };
ProbabilityTable table = new ProbabilityTable(names);
return table;
}
public static ProbabilityDistribution tomatos() {
String names[] = { CONTAINS_VEGETABLE, CONTAINS_TOMATOS };
ProbabilityTable table = new ProbabilityTable(names);
return table;
}
public static ProbabilityDistribution potatos() {
String names[] = { CONTAINS_VEGETABLE, CONTAINS_POTATOS };
ProbabilityTable table = new ProbabilityTable(names);
return table;
}
public static ProbabilityDistribution vegetables() {
String names[] = { CONTAINS_VEGETABLE, SOMEONE_VEGETARIAN };
ProbabilityTable table = new ProbabilityTable(names);
return table;
}
public static ProbabilityDistribution taste() {
String names[] = { TASTE, CONTAINS_BEEF, CONTAINS_PORK,
CONTAINS_POTATOS, CONTAINS_TOMATOS };
ContinousDistribution distribution = new ContinousDistribution(names, 0);
return distribution;
}
public static BayesNet dishNet() {
BayesNet net = new BayesNet(VARIABLES);
net.setDistribution(new Variable(SOMEONE_VEGETARIAN, DOMAIN), vegi());
net.setDistribution(new Variable(CONTAINS_MEET, DOMAIN), meet());
net.setDistribution(new Variable(CONTAINS_VEGETABLE, DOMAIN),
vegetables());
net.setDistribution(new Variable(CONTAINS_BEEF, DOMAIN), beef());
net.setDistribution(new Variable(CONTAINS_PORK, DOMAIN), pork());
net.setDistribution(new Variable(CONTAINS_POTATOS, DOMAIN), potatos());
net.setDistribution(new Variable(CONTAINS_TOMATOS, DOMAIN), tomatos());
net.setDistribution(new Variable(TASTE, RATING_DOMAIN), taste());
Ontology onthology = onto();
for (String category : onthology.getClasses()) {
net.connect(category, SOMEONE_VEGETARIAN);
}
for (String thing : OBSERVED) {
net.connect(thing, onthology.getInheritance().get(thing));
net.connect(TASTE, thing);
}
for (String category : onthology.getClasses()) {
MaximumLikelihoodEstimation.estimate(examples(), net, category);
for (String thing : onthology.getClasses2thing().get(category)) {
MaximumLikelihoodEstimation.estimate(examples(), net, thing);
}
}
MaximumLikelihoodEstimation.estimate(examples(), net, TASTE);
ContinousDistribution distribturion = (ContinousDistribution) net
.getNodes().get(TASTE);
distribturion.estimate();
return net;
}
}

View File

@@ -32,5 +32,9 @@ public class SurveyDatasetReaderTest {
assertFalse(recipe.getIngredients().contains(TYPE.RED_MEAT)); assertFalse(recipe.getIngredients().contains(TYPE.RED_MEAT));
assertFalse(recipe.getIngredients().contains(TYPE.POULTRY)); assertFalse(recipe.getIngredients().contains(TYPE.POULTRY));
assertFalse(recipe.getIngredients().contains(TYPE.SHELLFISH)); assertFalse(recipe.getIngredients().contains(TYPE.SHELLFISH));
for (int rIndex = 0; rIndex < recipeBook.getSize(); rIndex++) {
System.out.println(recipeBook.getRecipe(rIndex).getHead().getTitle());
}
} }
} }