/** * <p>Returns the sum of squared deviations of Y from its mean.</p> * * <p>If the model has no intercept term, <code>0</code> is used for the * mean of Y - i.e., what is returned is the sum of the squared Y values.</p> * * <p>The value returned by this method is the SSTO value used in * the {@link #calculateRSquared() R-squared} computation.</p> * * @return SSTO - the total sum of squares * @throws NullPointerException if the sample has not been set * @see #isNoIntercept() * @since 2.2 */ public double calculateTotalSumOfSquares() { if (isNoIntercept()) { return StatUtils.sumSq(getY().toArray()); } else { return new SecondMoment().evaluate(getY().toArray()); } }
/** * <p>Returns the adjusted R-squared statistic, defined by the formula <pre> * R<sup>2</sup><sub>adj</sub> = 1 - [SSR (n - 1)] / [SSTO (n - p)] * </pre> * where SSR is the {@link #calculateResidualSumOfSquares() sum of squared residuals}, * SSTO is the {@link #calculateTotalSumOfSquares() total sum of squares}, n is the number * of observations and p is the number of parameters estimated (including the intercept).</p> * * <p>If the regression is estimated without an intercept term, what is returned is <pre> * <code> 1 - (1 - {@link #calculateRSquared()}) * (n / (n - p)) </code> * </pre></p> * * <p>If there is no variance in y, i.e., SSTO = 0, NaN is returned.</p> * * @return adjusted R-Squared statistic * @throws NullPointerException if the sample has not been set * @throws org.apache.commons.math3.linear.SingularMatrixException if the design matrix is singular * @see #isNoIntercept() * @since 2.2 */ public double calculateAdjustedRSquared() { final double n = getX().getRowDimension(); if (isNoIntercept()) { return 1 - (1 - calculateRSquared()) * (n / (n - getX().getColumnDimension())); } else { return 1 - (calculateResidualSumOfSquares() * (n - 1)) / (calculateTotalSumOfSquares() * (n - getX().getColumnDimension())); } }
@Override boolean hasConstant() { return !R.isNoIntercept(); }
@Override double predict(List<Double> given) { if (given.size() != numVars) throw new IllegalArgumentException("incorrect number of variables in given."); if (this.state == State.training) train(); double result = 0; if (R.isNoIntercept()) { for (int i = 0; i < numVars; i++) result += params[i] * given.get(i); } else { result += params[0]; for (int i = 0; i < numVars; i++) result += params[i + 1] * given.get(i); } return result; }
/** * <p>Returns the sum of squared deviations of Y from its mean.</p> * * <p>If the model has no intercept term, <code>0</code> is used for the * mean of Y - i.e., what is returned is the sum of the squared Y values.</p> * * <p>The value returned by this method is the SSTO value used in * the {@link #calculateRSquared() R-squared} computation.</p> * * @return SSTO - the total sum of squares * @throws NullPointerException if the sample has not been set * @see #isNoIntercept() * @since 2.2 */ public double calculateTotalSumOfSquares() { if (isNoIntercept()) { return StatUtils.sumSq(getY().toArray()); } else { return new SecondMoment().evaluate(getY().toArray()); } }
/** * <p>Returns the sum of squared deviations of Y from its mean.</p> * * <p>If the model has no intercept term, <code>0</code> is used for the * mean of Y - i.e., what is returned is the sum of the squared Y values.</p> * * <p>The value returned by this method is the SSTO value used in * the {@link #calculateRSquared() R-squared} computation.</p> * * @return SSTO - the total sum of squares * @throws NullPointerException if the sample has not been set * @see #isNoIntercept() * @since 2.2 */ public double calculateTotalSumOfSquares() { if (isNoIntercept()) { return StatUtils.sumSq(getY().toArray()); } else { return new SecondMoment().evaluate(getY().toArray()); } }
/** * <p>Returns the adjusted R-squared statistic, defined by the formula <pre> * R<sup>2</sup><sub>adj</sub> = 1 - [SSR (n - 1)] / [SSTO (n - p)] * </pre> * where SSR is the {@link #calculateResidualSumOfSquares() sum of squared residuals}, * SSTO is the {@link #calculateTotalSumOfSquares() total sum of squares}, n is the number * of observations and p is the number of parameters estimated (including the intercept).</p> * * <p>If the regression is estimated without an intercept term, what is returned is <pre> * <code> 1 - (1 - {@link #calculateRSquared()}) * (n / (n - p)) </code> * </pre></p> * * <p>If there is no variance in y, i.e., SSTO = 0, NaN is returned.</p> * * @return adjusted R-Squared statistic * @throws NullPointerException if the sample has not been set * @throws org.apache.commons.math3.linear.SingularMatrixException if the design matrix is singular * @see #isNoIntercept() * @since 2.2 */ public double calculateAdjustedRSquared() { final double n = getX().getRowDimension(); if (isNoIntercept()) { return 1 - (1 - calculateRSquared()) * (n / (n - getX().getColumnDimension())); } else { return 1 - (calculateResidualSumOfSquares() * (n - 1)) / (calculateTotalSumOfSquares() * (n - getX().getColumnDimension())); } }
/** * <p>Returns the adjusted R-squared statistic, defined by the formula <pre> * R<sup>2</sup><sub>adj</sub> = 1 - [SSR (n - 1)] / [SSTO (n - p)] * </pre> * where SSR is the {@link #calculateResidualSumOfSquares() sum of squared residuals}, * SSTO is the {@link #calculateTotalSumOfSquares() total sum of squares}, n is the number * of observations and p is the number of parameters estimated (including the intercept).</p> * * <p>If the regression is estimated without an intercept term, what is returned is <pre> * <code> 1 - (1 - {@link #calculateRSquared()}) * (n / (n - p)) </code> * </pre></p> * * <p>If there is no variance in y, i.e., SSTO = 0, NaN is returned.</p> * * @return adjusted R-Squared statistic * @throws NullPointerException if the sample has not been set * @throws org.apache.commons.math3.linear.SingularMatrixException if the design matrix is singular * @see #isNoIntercept() * @since 2.2 */ public double calculateAdjustedRSquared() { final double n = getX().getRowDimension(); if (isNoIntercept()) { return 1 - (1 - calculateRSquared()) * (n / (n - getX().getColumnDimension())); } else { return 1 - (calculateResidualSumOfSquares() * (n - 1)) / (calculateTotalSumOfSquares() * (n - getX().getColumnDimension())); } }