def makeTargetMfig(Rfree, DiscFac, CRRA, permShkStd, TranShkStd):
inf_hor = IndShockConsumerType(quietly=True, **base_params)
inf_hor.Rfree = Rfree
inf_hor.DiscFac = DiscFac
inf_hor.CRRA = CRRA
inf_hor.permShkStd = [permShkStd]
inf_hor.TranShkStd = [TranShkStd]
inf_hor.update_income_process()
mPlotMin = 0
mPlotMax = 250
inf_hor.aXtraMax = mPlotMax
inf_hor.solve(quietly=True, messaging_level=logging.CRITICAL)
soln = inf_hor.solution[0]
Bilt, cFunc = soln.Bilt, soln.cFunc
cPlotMin = 0, cFunc(mPlotMax)
if Bilt.GICNrm: # tattle
soln.check_GICNrm(soln, quietly=False, messaging_level=logging.WARNING)
mBelwStE = np.linspace(mPlotMin, mPlotMax, 1000)
EPermGroFac = inf_hor.PermGroFac[0]
def EmDelEq0(mVec):
return (EPermGroFac / Rfree) + (1.0 - EPermGroFac / Rfree) * mVec
cBelwStE_Best = cFunc(mBelwStE) # "best" = optimal c
cBelwStE_Sstn = EmDelEq0(mBelwStE) # "sustainable" c
mNrmStE = Bilt.mNrmStE
plt.figure(figsize=(12, 8))
plt.plot(mBelwStE, cBelwStE_Best, label="$c(m_{t})$")
plt.plot(mBelwStE,
cBelwStE_Sstn,
label="$\mathsf{E}_{t}[\Delta m_{t+1}] = 0$")
plt.xlim(mPlotMin, mPlotMax)
plt.ylim(cPlotMin, cFunc(mPlotMax))
plt.plot(
[mNrmStE, mNrmStE],
[0, 2.5],
color="black",
linestyle="--",
)
plt.tick_params(
# labelbottom=False,
# labelleft=False,
# left="off",
right="off",
# bottom="off",
top="off",
)
plt.text(0, 1.47, r"$c$", fontsize=26)
plt.text(3.02, 0, r"$m$", fontsize=26)
plt.text(mNrmStE - 0.05, -0.1, "m̌", fontsize=26)
plt.legend(fontsize='x-large')
plt.show()
return None
def makeTargetMfig(Rfree, DiscFac, CRRA, PermShkStd, TranShkStd):
baseAgent_Inf = IndShockConsumerType(verbose=0, cycles=0, **base_params)
baseAgent_Inf.Rfree = Rfree
baseAgent_Inf.DiscFac = DiscFac
baseAgent_Inf.CRRA = CRRA
baseAgent_Inf.PermShkStd = [PermShkStd]
baseAgent_Inf.TranShkStd = [TranShkStd]
baseAgent_Inf.updateIncomeProcess()
baseAgent_Inf.checkConditions()
mPlotMin = 0
mPlotMax = 250
baseAgent_Inf.aXtraMax = mPlotMax
baseAgent_Inf.solve()
baseAgent_Inf.unpack('cFunc')
cPlotMin = 0
cPlotMax = baseAgent_Inf.cFunc[0](mPlotMax)
if (baseAgent_Inf.GPFInd >= 1):
baseAgent_Inf.checkGICInd(verbose=3)
mBelwTrg = np.linspace(mPlotMin, mPlotMax, 1000)
EPermGroFac = baseAgent_Inf.PermGroFac[0]
EmDelEq0 = lambda m: (EPermGroFac / Rfree) + (1.0 - EPermGroFac / Rfree
) * m
cBelwTrg_Best = baseAgent_Inf.cFunc[0](mBelwTrg) # "best" = optimal c
cBelwTrg_Sstn = EmDelEq0(mBelwTrg) # "sustainable" c
mNrmTrg = baseAgent_Inf.solution[0].mNrmSS
plt.figure(figsize=(12, 8))
plt.plot(mBelwTrg, cBelwTrg_Best, label="$c(m_{t})$")
plt.plot(mBelwTrg,
cBelwTrg_Sstn,
label="$\mathsf{E}_{t}[\Delta m_{t+1}] = 0$")
plt.xlim(mPlotMin, mPlotMax)
plt.ylim(cPlotMin, cPlotMax)
plt.plot(
[mNrmTrg, mNrmTrg],
[0, 2.5],
color="black",
linestyle="--",
)
plt.tick_params(
# labelbottom=False,
# labelleft=False,
# left="off",
right="off",
# bottom="off",
top="off",
)
plt.text(0, 1.47, r"$c$", fontsize=26)
plt.text(3.02, 0, r"$m$", fontsize=26)
plt.text(mNrmTrg - 0.05, -0.1, "m̌", fontsize=26)
plt.legend(fontsize='x-large')
plt.show()
return None
GICNrmFailsButGICRawHolds.solve(quietly=True) # Suppress output # Because we are trying to solve a problem very close to the critical patience # values, we want to do it with extra precision to be sure we've gotten the # answer right. We can retrieve the distance between the last two solutions: distance_original = GICNrmFailsButGICRawHolds.solution[0].distance_last # But high precision would have slowed things down if we used it from the start # Instead, we can take the solution obtained above, and continue it but with # parameters that will yield a more precise answer: # Solve with quadruple the normal range GICNrmFailsButGICRawHolds.aXtraMax = GICNrmFailsButGICRawHolds.aXtraMax * 10 # Solve over four times as many gridpoints GICNrmFailsButGICRawHolds.aXtraCount = GICNrmFailsButGICRawHolds.aXtraCount * 4 GICNrmFailsButGICRawHolds.update_assets_grid() # Solve to a 10 times tighter degree of error tolerance GICNrmFailsButGICRawHolds.tolerance = GICNrmFailsButGICRawHolds.tolerance/10 # When the solver reaches its tolerance threshold, it changes the solver # attribute stge_kind to have 'iter_status' of 'finished' # If we want to continue the solution (having changed something, as above) # To continue the solution from where we left off, we just change the # 'iter_status' to 'iterator' and tell it to ".solve()" again
def makeBoundsFigure(UnempPrb, permShkStd, TranShkStd, DiscFac, CRRA):
inf_hor = IndShockConsumerType(quietly=True,
messaging_level=logging.CRITICAL,
**base_params)
inf_hor.UnempPrb = UnempPrb
inf_hor.permShkStd = [permShkStd]
inf_hor.TranShkStd = [TranShkStd]
inf_hor.DiscFac = DiscFac
inf_hor.CRRA = CRRA
inf_hor.update_income_process()
inf_hor.solve(quietly=True, messaging_level=logging.CRITICAL)
soln = inf_hor.solution[0]
Bilt, Pars = soln.Bilt, soln.Pars
cFunc = soln.cFunc
mPlotMin, mPlotMax = 0, 25
inf_hor.aXtraMax = mPlotMax
# Retrieve parameters (makes code more readable)
Rfree, EPermGroFac = Pars.Rfree, Pars.PermGroFac
κ_Min = 1.0 - (Rfree**(-1.0)) * (Rfree * DiscFac)**(1.0 / CRRA)
h_inf = (1.0 / (1.0 - EPermGroFac / Rfree))
def cFunc_Uncnst(mVec):
return (h_inf - 1) * κ_Min + κ_Min * mVec
def cFunc_TopBnd(mVec):
return (1 - UnempPrb**(1.0 / CRRA) *
(Rfree * DiscFac)**(1.0 / CRRA) / Rfree) * mVec
def cFunc_BotBnd(mVec):
return (1 - (Rfree * DiscFac)**(1.0 / CRRA) / Rfree) * mVec
# Plot the consumption function and its bounds
cPlotMaxLabel = r"c̅$(m) = (m-1+h)κ̲$" # Use unicode kludge
cPlotMinLabel = r"c̲$(m)= (1-\Phi_{R})m = κ̲ m$"
# mKnk is point where the two upper bounds meet
mKnk = ((h_inf - 1) * κ_Min) / (
(1 - UnempPrb**(1.0 / CRRA) *
(Rfree * DiscFac)**(1.0 / CRRA) / Rfree) - κ_Min)
mBelwKnkPts, mAbveKnkPts = 50, 100
mBelwKnk = np.linspace(mPlotMin, mKnk, mBelwKnkPts)
mAbveKnk = np.linspace(mKnk, mPlotMax, mAbveKnkPts)
mFullPts = np.linspace(mPlotMin, mPlotMax, mBelwKnkPts + mAbveKnkPts)
plt.figure(figsize=(12, 8))
plt.plot(mFullPts, cFunc(mFullPts), label=r'$c(m)$')
plt.plot(mBelwKnk,
cFunc_Uncnst(mBelwKnk),
label=cPlotMaxLabel,
linestyle="--")
plt.plot(
mAbveKnk,
cFunc_Uncnst(mAbveKnk),
label=
r'Upper Bound $ = $ Min $[\overline{\overline{c}}(m),\overline{c}(m)]$',
linewidth=2.5,
color='black')
plt.plot(mBelwKnk, cFunc_TopBnd(mBelwKnk), linewidth=2.5, color='black')
plt.plot(mAbveKnk,
cFunc_TopBnd(mAbveKnk),
linestyle="--",
label=r"$\overline{\overline{c}}(m) = κ̅m = (1 - ℘^{1/ρ}Φᵣ)m$")
plt.plot(mBelwKnk, cFunc_BotBnd(mBelwKnk), color='red', linewidth=2.5)
plt.plot(mAbveKnk,
cFunc_BotBnd(mAbveKnk),
color='red',
label=cPlotMinLabel,
linewidth=2.5)
plt.tick_params(labelbottom=False,
labelleft=False,
left='off',
right='off',
bottom='off',
top='off')
plt.xlim(mPlotMin, mPlotMax)
plt.ylim(mPlotMin, 1.12 * cFunc_Uncnst(mPlotMax))
plt.text(mPlotMin,
1.12 * cFunc_Uncnst(mPlotMax) + 0.05,
"$c$",
fontsize=22)
plt.text(mPlotMax + 0.1, mPlotMin, "$m$", fontsize=22)
plt.legend(fontsize='x-large')
plt.show()
return None
def makeBoundsFigure(UnempPrb, PermShkStd, TranShkStd, DiscFac, CRRA):
baseAgent_Inf = IndShockConsumerType(verbose=0, cycles=0, **base_params)
baseAgent_Inf.UnempPrb = UnempPrb
baseAgent_Inf.PermShkStd = [PermShkStd]
baseAgent_Inf.TranShkStd = [TranShkStd]
baseAgent_Inf.DiscFac = DiscFac
baseAgent_Inf.CRRA = CRRA
baseAgent_Inf.updateIncomeProcess()
baseAgent_Inf.checkConditions()
mPlotMin = 0
mPlotMax = 2500
baseAgent_Inf.tolerance = 1e-09
baseAgent_Inf.aXtraMax = mPlotMax
baseAgent_Inf.solve(verbose=0)
baseAgent_Inf.unpack('cFunc')
cPlotMin = 0
cPlotMax = 1.2 * baseAgent_Inf.cFunc[0](mPlotMax)
# Retrieve parameters (makes code more readable)
Rfree = baseAgent_Inf.Rfree
CRRA = baseAgent_Inf.CRRA
EPermGroFac = baseAgent_Inf.PermGroFac[0]
mNrmTrg = baseAgent_Inf.solution[0].mNrmSS
UnempPrb = baseAgent_Inf.UnempPrb
κ_Min = 1.0 - (Rfree**(-1.0)) * (Rfree * DiscFac)**(1.0 / CRRA)
h_inf = (1.0 / (1.0 - EPermGroFac / Rfree))
cFunc_Uncnst = lambda m: (h_inf - 1) * κ_Min + κ_Min * m
cFunc_TopBnd = lambda m: (1 - UnempPrb**(1.0 / CRRA) *
(Rfree * DiscFac)**(1.0 / CRRA) / Rfree) * m
cFunc_BotBnd = lambda m: (1 - (Rfree * DiscFac)**(1.0 / CRRA) / Rfree) * m
# Plot the consumption function and its bounds
cMaxLabel = r"c̅$(m) = (m-1+h)κ̲$" # Use unicode kludge
cMinLabel = r"c̲$(m)= (1-\Phi_{R})m = κ̲ m$"
# mKnk is point where the two upper bounds meet
mKnk = ((h_inf - 1) * κ_Min) / (
(1 - UnempPrb**(1.0 / CRRA) *
(Rfree * DiscFac)**(1.0 / CRRA) / Rfree) - κ_Min)
mBelwKnkPts = 300
mAbveKnkPts = 700
mBelwKnk = np.linspace(mPlotMin, mKnk, mBelwKnkPts)
mAbveKnk = np.linspace(mKnk, mPlotMax, mAbveKnkPts)
mFullPts = np.linspace(mPlotMin, mPlotMax, mBelwKnkPts + mAbveKnkPts)
plt.figure(figsize=(12, 8))
plt.plot(mFullPts, baseAgent_Inf.cFunc[0](mFullPts), label=r'$c(m)$')
plt.plot(mBelwKnk, cFunc_Uncnst(mBelwKnk), label=cMaxLabel, linestyle="--")
plt.plot(
mAbveKnk,
cFunc_Uncnst(mAbveKnk),
label=
r'Upper Bound $ = $ Min $[\overline{\overline{c}}(m),\overline{c}(m)]$',
linewidth=2.5,
color='black')
plt.plot(mBelwKnk, cFunc_TopBnd(mBelwKnk), linewidth=2.5, color='black')
plt.plot(mAbveKnk,
cFunc_TopBnd(mAbveKnk),
linestyle="--",
label=r"$\overline{\overline{c}}(m) = κ̅m = (1 - ℘^{1/ρ}Φᵣ)m$")
plt.plot(mBelwKnk, cFunc_BotBnd(mBelwKnk), color='red', linewidth=2.5)
plt.plot(mAbveKnk,
cFunc_BotBnd(mAbveKnk),
color='red',
label=cMinLabel,
linewidth=2.5)
plt.tick_params(labelbottom=False,
labelleft=False,
left='off',
right='off',
bottom='off',
top='off')
plt.xlim(mPlotMin, mPlotMax)
plt.ylim(mPlotMin, 1.12 * cFunc_Uncnst(mPlotMax))
plt.text(mPlotMin,
1.12 * cFunc_Uncnst(mPlotMax) + 0.05,
"$c$",
fontsize=22)
plt.text(mPlotMax + 0.1, mPlotMin, "$m$", fontsize=22)
plt.legend(fontsize='x-large')
plt.show()
return None
def makeGrowthplot(PermGroFac, DiscFac):
# cycles=0 tells the solver to find the infinite horizon solution
baseAgent_Inf = IndShockConsumerType(verbose=0, cycles=0, **base_params)
baseAgent_Inf.PermGroFac = [PermGroFac]
baseAgent_Inf.DiscFac = DiscFac
baseAgent_Inf.updateIncomeProcess()
baseAgent_Inf.checkConditions()
mPlotMin = 0
mPlotMax = 3500.5
baseAgent_Inf.mPlotMax = 3500.5
baseAgent_Inf.aXtraMax = mPlotMax
baseAgent_Inf.tolerance = 1e-09
baseAgent_Inf.solve()
baseAgent_Inf.unpack('cFunc')
numPts = 500
if (baseAgent_Inf.GPFInd >= 1):
baseAgent_Inf.checkGICInd(verbose=3)
elif baseAgent_Inf.solution[0].mNrmSS > mPlotMax:
print('Target exists but is outside the plot range.')
else:
def EcLev_tp1_Over_p_t(a):
'''
Taking end-of-period assets a as input, return ratio of expectation
of next period's consumption to this period's permanent income
Inputs:
a: end-of-period assets
Returns:
EcLev_tp1_Over_p_{t}: next period's expected c level / current p
'''
# Extract parameter values to make code more readable
permShkVals = baseAgent_Inf.PermShkDstn[0].X
tranShkVals = baseAgent_Inf.TranShkDstn[0].X
permShkPrbs = baseAgent_Inf.PermShkDstn[0].pmf
tranShkPrbs = baseAgent_Inf.TranShkDstn[0].pmf
Rfree = baseAgent_Inf.Rfree
EPermGroFac = baseAgent_Inf.PermGroFac[0]
PermGrowFac_tp1 = EPermGroFac * permShkVals # Nonstochastic growth times idiosyncratic permShk
RNrmFac_tp1 = Rfree / PermGrowFac_tp1 # Growth-normalized interest factor
# 'bank balances' b = end-of-last-period assets times normalized return factor
b_tp1 = RNrmFac_tp1 * a
# expand dims of b_tp1 and use broadcasted sum of a column and a row vector
# to obtain a matrix of possible market resources next period
# because matrix mult is much much faster than looping to calc E
m_tp1_GivenTranAndPermShks = np.expand_dims(b_tp1,
axis=1) + tranShkVals
# List of possible values of $\mathbf{c}_{t+1}$ (Transposed by .T)
cRat_tp1_GivenTranAndPermShks = baseAgent_Inf.cFunc[0](
m_tp1_GivenTranAndPermShks).T
cLev_tp1_GivenTranAndPermShks = cRat_tp1_GivenTranAndPermShks * PermGrowFac_tp1
# compute expectation over perm shocks by right multiplying with probs
EOverPShks_cLev_tp1_GivenTranShkShks = np.dot(
cLev_tp1_GivenTranAndPermShks, permShkPrbs)
# finish expectation over trans shocks by right multiplying with probs
EcLev_tp1_Over_p_t = np.dot(EOverPShks_cLev_tp1_GivenTranShkShks,
tranShkPrbs)
# return expected consumption
return EcLev_tp1_Over_p_t
# Calculate the expected consumption growth factor
# mBelwTrg defines the plot range on the left of target m value (e.g. m <= target m)
mNrmTrg = baseAgent_Inf.solution[0].mNrmSS
mPlotMin = 0
mPlotMax = 200
mBelwTrg = np.linspace(mPlotMin, mNrmTrg, numPts)
c_For_mBelwTrg = baseAgent_Inf.cFunc[0](mBelwTrg)
a_For_mBelwTrg = mBelwTrg - c_For_mBelwTrg
EcLev_tp1_Over_p_t_For_mBelwTrg = [
EcLev_tp1_Over_p_t(i) for i in a_For_mBelwTrg
]
# mAbveTrg defines the plot range on the right of target m value (e.g. m >= target m)
mAbveTrg = np.linspace(mNrmTrg, mPlotMax, numPts)
# EcGro_For_mAbveTrg: E [consumption growth factor] when m_{t} is below target m
EcGro_For_mBelwTrg = np.array(
EcLev_tp1_Over_p_t_For_mBelwTrg) / c_For_mBelwTrg
c_For_mAbveTrg = baseAgent_Inf.cFunc[0](mAbveTrg)
a_For_mAbveTrg = mAbveTrg - c_For_mAbveTrg
EcLev_tp1_Over_p_t_For_mAbveTrg = [
EcLev_tp1_Over_p_t(i) for i in a_For_mAbveTrg
]
# EcGro_For_mAbveTrg: E [consumption growth factor] when m_{t} is bigger than target m_{t}
EcGro_For_mAbveTrg = np.array(
EcLev_tp1_Over_p_t_For_mAbveTrg) / c_For_mAbveTrg
Rfree = 1.0
EPermGroFac = 1.0
mNrmTrg = baseAgent_Inf.solution[0].mNrmSS
# Calculate Absolute Patience Factor Phi = lower bound of consumption growth factor
APF = (Rfree * DiscFac)**(1.0 / CRRA)
plt.figure(figsize=(12, 8))
# Plot the Absolute Patience Factor line
plt.plot([mPlotMin, mPlotMax], [APF, APF],
label="\u03A6 = [(\u03B2 R)^(1/ \u03C1)]/R")
# Plot the Permanent Income Growth Factor line
plt.plot([mPlotMin, mPlotMax], [EPermGroFac, EPermGroFac],
label="\u0393")
# Plot the expected consumption growth factor on the left side of target m
plt.plot(mBelwTrg, EcGro_For_mBelwTrg, color="black")
# Plot the expected consumption growth factor on the right side of target m
plt.plot(mAbveTrg,
EcGro_For_mAbveTrg,
color="black",
label="$\mathsf{E}_{t}[c_{t+1}/c_{t}]$")
# Plot the target m
plt.plot(
[mNrmTrg, mNrmTrg],
[mPlotMin, mPlotMax],
color="black",
linestyle="--",
label="",
)
plt.xlim(1, mPlotMax)
plt.ylim(0.94, 1.10)
plt.text(2.105, 0.930, "$m_{t}$", fontsize=26, fontweight="bold")
plt.text(
mNrmTrg - 0.02,
0.930,
"m̌",
fontsize=26,
fontweight="bold",
)
plt.tick_params(
labelbottom=False,
labelleft=False,
left="off",
right="off",
bottom="off",
top="off",
)
plt.legend(fontsize='x-large')
plt.show()
return None
