objective

Calculate the objective (i.e. the negative log-likelihood) function using a wrapper for a given stochastic process

Parameters:
  • params (list) –

    The input values representing parameters for the stochastic process.

  • process (Any | None, default: None ) –

    An instance of a stochastic process object

  • observations (DataFrame | DataFrame | None, default: None ) –

    The observation data used for calculating the log-likelihood

  • delta (float, default: 1.0 ) –

    The sampling frequency or time step used in the observations

Returns:
  • float

    the negative log-likelihood value

Notes
  • If the provided parameters lead to an invalid computation (e.g., due to invalid input or model constraints), the function returns positive infinity (np.inf).
  • The log-likelihood value returned is negated to align with optimization conventions, where the objective is typically minimized.