# Options

## Options structure

Most RECS functions can have their behavior changed by adjusting options. Options take the form of a structure whose possible fields are described in the following table. You can set values of these fields using either of the two formulations:

options = struct('field1', values1, 'field2', values2, ...);

or

options.field1 = values1;
options.field2 = values2;

List of RECS options
Field name Values Used by Functions
accuracy 1 to check accuracy on the asymptotic distribution (default: 0). recsSimul
display 1 (default) to display output (solver iterations or results), 0 to prevent display. recsAccuracy, recsmodel, recsSimul, recsSolveREE
eqsolver Solver for equilibrium equations: 'fsolve', 'lmmcp' (default), 'ncpsolve' or 'path', see Solvers for systems of nonlinear equations and for mixed complementarity problems. recsFirstGuess, recsmodel, recsSimul, recsSolveREE, recsSS
eqsolveroptions Options structure to be passed to eqsolver. recsFirstGuess, recsmodel, recsSimul, recsSolveREE, recsSS
extrapolate 1 (default) if extrapolation is allowed outside the interpolation space or 0 to forbid it. recsSimul, recsSolveREE
fgmethod Determine which method is used to provide a first guess: 'auto' (default), 'perturbation', 'perfect-foresight' or 'steady-state' recsFirstGuess
funapprox Functional approximated to find the rational expectations solution:
• 'expapprox': expectations (variables z), similar to the parameterized expectations approach of den Haan and Marcet (1990).
• 'expfunapprox': expectations function (function h).
• 'resapprox' (default): response variables (variables x).
recsSimul, recsSolveREE
loop_over_s 0 (default) to solve all grid points at once, 1 to loop over each grid points, or n to loop over n blocks of grid points. recsSolveREE, recsSimul
Python 1 to call Python directly instead of the executable file (default: 0, only for Windows and for developement). recsmodel
reemethod Define the method to solve for rational expextations:
• 'iter' (default): time iteration.
• '1-step': rational expectations and equilibrium equations are solved in one step (as suggested in Judd, 1992).
recsSolveREE
reesolver Solver for the rational expectations equilibrium, expected values depend on reemethod:
recsSolveREE
reesolveroptions Options structure to be passed to reesolver. recsSolveREE
simulmethod Method of simulation: 'interpolation' (default) or 'solve', see Simulate the model. recsSimul
stat 1 to ouput summary statistics from the simulation (default: 0), see Simulate the model. recsSimul
useapprox (default: 1) behaviour dependent of the chosen function to approximate. If 0 and funapprox is 'expapprox' then next-period responses are calculated by equations solve and not just interpolated. If 1 and funapprox is 'resapprox', the guess of response variables is found with the new approximation structure. recsSimul, recsSolveREE
T integer defining the time horizon at which the model is supposed to converge to its steady state (default: 50) recsFirstGuess
Tburn integer defining the number of observations discarded as burn-in period (default: 20) recsSimul

## References

den Haan, W. J. and Marcet, A. (1990). Solving the Stochastic Growth Model by Parameterizing Expectations. Journal of Business & Economic Statistics, 8(1), 31-34.

Judd, K. (1992). Projection Methods for Solving Aggregate Growth Models. Journal of Economic Theory, 58(2), 410-452.