# Exogenous Parameters¶

[TODO: This chapter needs heavy updating. Would be nice to do something similar to API chapter. But it is also nice to have references and descriptions as in the table below.]

In this chapter, list the exogenous inputs to the model, options, and where the values come from (weak calibration vs. strong calibration). Point to the respective chapters for some of the inputs. Mention the code in default_parameters.json and parameters.py.

Table 1 List of exogenous parameters and baseline calibration values.

Symbol

Description

Value

$$S$$

Maximum periods in economically active household life

80

$$E$$

Number of periods of youth economically outside the model

$$\text{round} \frac{S}{4}$$=20

$$R$$

Retirement age (period)

$$E + \text{round} (\frac{9}{16} S) = 65$$

$$T_1$$

Number of periods to steady state for initial time path guesses

160

$$T_2$$

160

$$\nu$$

Dampening parameter for TPI

0.4

$${ \{ { \{ \omega_{s,0} \} }_{s=1}^{E+S} \}}_{t=0}^{T_2 + S - 1}$$

Initial population distribution by age

(see Chap. Demographics)

$${ \{ f_s \}}_{s=1}^{E+S}$$

Fertility rates by age

(see Sec. Fertility rates)

$${ \{ i_s \}}_{s=1}^{E+S}$$

Immigration rates by age

(see Sec. Mortality rates)

$${ \{ \rho_s \}}_{s=0}^{E+S}$$

Mortality rates by age

(see Sec. Immigration rates)