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regression_distribution.hpp
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1 
12 #ifndef MLPACK_CORE_DISTRIBUTIONS_REGRESSION_DISTRIBUTION_HPP
13 #define MLPACK_CORE_DISTRIBUTIONS_REGRESSION_DISTRIBUTION_HPP
14 
15 #include <mlpack/prereqs.hpp>
18 
19 namespace mlpack {
20 namespace distribution {
21 
31 {
32  private:
37 
38  public:
42  RegressionDistribution() { /* nothing to do */ }
43 
51  RegressionDistribution(const arma::mat& predictors,
52  const arma::vec& responses) :
53  rf(regression::LinearRegression(predictors, responses))
54  {
55  err = GaussianDistribution(1);
56  arma::mat cov(1, 1);
57  cov(0, 0) = rf.ComputeError(predictors, responses);
58  err.Covariance(std::move(cov));
59  }
60 
64  template<typename Archive>
65  void Serialize(Archive& ar, const unsigned int /* version */)
66  {
67  ar & data::CreateNVP(rf, "rf");
68  ar & data::CreateNVP(err, "err");
69  }
70 
72  const regression::LinearRegression& Rf() const { return rf; }
75 
77  const GaussianDistribution& Err() const { return err; }
79  GaussianDistribution& Err() { return err; }
80 
86  void Train(const arma::mat& observations);
87 
93  void Train(const arma::mat& observations, const arma::vec& weights);
94 
100  double Probability(const arma::vec& observation) const;
101 
107  double LogProbability(const arma::vec& observation) const {
108  return log(Probability(observation));
109  }
110 
117  void Predict(const arma::mat& points, arma::vec& predictions) const;
118 
120  const arma::vec& Parameters() const { return rf.Parameters(); }
121 
123  size_t Dimensionality() const { return rf.Parameters().n_elem; }
124 };
125 
126 
127 } // namespace distribution
128 } // namespace mlpack
129 
130 #endif
A single multivariate Gaussian distribution.
const arma::vec & Parameters() const
Return the parameters (the b vector).
Linear algebra utility functions, generally performed on matrices or vectors.
Definition: binarize.hpp:18
A simple linear regression algorithm using ordinary least squares.
const GaussianDistribution & Err() const
Return error distribution.
RegressionDistribution()
Default constructor, which creates a Gaussian with zero dimension.
void Predict(const arma::mat &points, arma::vec &predictions) const
Calculate y_i for each data point in points.
The core includes that mlpack expects; standard C++ includes and Armadillo.
FirstShim< T > CreateNVP(T &t, const std::string &name, typename std::enable_if_t< HasSerialize< T >::value > *=0)
Call this function to produce a name-value pair; this is similar to BOOST_SERIALIZATION_NVP(), but should be used for types that have a Serialize() function (or contain a type that has a Serialize() function) instead of a serialize() function.
void Train(const arma::mat &observations)
Estimate the Gaussian distribution directly from the given observations.
RegressionDistribution(const arma::mat &predictors, const arma::vec &responses)
Create a Conditional Gaussian distribution with conditional mean function obtained by running Regress...
double Probability(const arma::vec &observation) const
Evaluate probability density function of given observation.
double ComputeError(const arma::mat &points, const arma::vec &responses) const
Calculate the L2 squared error on the given predictors and responses using this linear regression mod...
double LogProbability(const arma::vec &observation) const
Evaluate log probability density function of given observation.
const regression::LinearRegression & Rf() const
Return regression function.
const arma::vec & Parameters() const
Return the parameters (the b vector).
size_t Dimensionality() const
Return the dimensionality.
A class that represents a univariate conditionally Gaussian distribution.
GaussianDistribution err
Error distribution.
regression::LinearRegression rf
Regression function for representing conditional mean.
void Serialize(Archive &ar, const unsigned int)
Serialize the distribution.
regression::LinearRegression & Rf()
Modify regression function.
const arma::mat & Covariance() const
Return the covariance matrix.
GaussianDistribution & Err()
Modify error distribution.