/** {@inheritDoc} */
  @Override
  public double[] getParameters() {

    int numParameters = 3 * coefficients.length;
    double[] parameters = new double[numParameters];

    int index = 0;
    for (Normal normal : this.terms) {
      parameters[3 * index] = this.coefficients[index];
      parameters[3 * index + 1] = normal.getMean();
      parameters[3 * index + 2] = normal.getVariance();
      index++;
    }
    return parameters;
  }