Exemple #1
0
 def compute_child_support_transitions(self,*,child_support_share):
     from interp_np import interp
     # this computes sets of transition matrices when in married couple
     # that breaks male gives away part of his income to wife. In this 
     # setup that means that productivity of male decreases and 
     # productivity of female increases.
     
     # structure: for each t there are indices of zf, probabilities of
     # zf, indices of zm, probabilities of zm
     
     p = self.pars
     transitions = list()
     
     for t in range(p['T']):
         trans_t = dict()
         
         
         
         
         trend_f = p['f_wage_trend'][t]
         trend_m = p['m_wage_trend'][t]
         zf_all = self.exogrid.zf_t[t]
         zm_all = self.exogrid.zm_t[t]
         
         if zf_all.size > 1 and zm_all.size>1:
             
             income_fem = np.exp(trend_f + zf_all)
             income_mal = np.exp(trend_m + zm_all)
             
             
             child_support = child_support_share*income_mal
             income_fem_adj = income_fem[:,None] + child_support[None,:]
             income_mal_adj = income_mal - child_support
             
             z_fem_adj = np.log(income_fem_adj) - trend_f
             z_mal_adj = np.log(income_mal_adj) - trend_m
             
             #von_fem = VecOnGrid(zf_all,z_fem_adj)
             trans_t['i_this_fem'], trans_t['w_this_fem'] = \
                 interp(zf_all,z_fem_adj,return_wnext=False,trim=True)
                 
             
             #von_mal = VecOnGrid(zm_all,z_mal_adj)
             trans_t['i_this_mal'], trans_t['w_this_mal'] = \
                 interp(zm_all,z_mal_adj,return_wnext=False,trim=True)
                 
         else:
             fill = np.array([-1],dtype=np.int16), np.array([0.0],dtype=self.dtype)
             trans_t['i_this_fem'], trans_t['w_this_fem'] = fill
             trans_t['i_this_mal'], trans_t['w_this_mal'] = fill
             
         
         transitions.append(trans_t)
     
     self.child_support_transitions = transitions
Exemple #2
0
    def __init__(self, grid, values, iwn=None, trim=True):
        # this assumes grid is strictly increasing o/w unpredictable
        self.val = values
        self.val_trimmed = np.clip(values, grid[0], grid[-1])
        self.grid = grid

        if iwn is None:
            self.i, self.wnext = interp(self.grid,
                                        self.val,
                                        return_wnext=True,
                                        trim=trim)
        else:
            self.i, self.wnext = iwn

        if np.any(self.i < 0):
            # manual correction to avoid -1
            ichange = (self.i < 0)
            assert np.allclose(self.wnext[ichange], 1.0)
            self.i[ichange] = 0
            self.wnext[ichange] = 0.0

        self.wnext = self.wnext.astype(grid.dtype)

        self.n = self.i.size

        self.one = np.array(1).astype(grid.dtype)  # sorry

        self.wthis = self.one - self.wnext
        self.trim = trim

        assert np.allclose(self.val_trimmed, self.apply_crude(grid))
Exemple #3
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    def update(self, where, values):
        # this replaces values at positions where with values passed to the
        # function and recomputes interpolation weights

        where, values = num_to_nparray(
            where, values)  # safety check in case of singletons

        assert (where.size == values.size) or (values.size == 1)

        if values.size == 1:
            values = values * np.ones(where.shape)

        self.val[where] = values
        self.i[where], self.wnext[where] = \
            interp(self.grid,self.val[where],return_wnext=True,trim=self.trim)
        self.wnext[where] = self.wnext[where].astype(self.dtype)
        self.wthis[where] = self.one - self.wnext[where]
Exemple #4
0
def v_compare(agrid, v_base, v_compare, *, a_mult):

    ia0 = 0

    names = [
        'extra assets in base to reach 0 in compare',
        'extra assets in compare to reach 0 in base'
    ]

    i = 0

    aall = list()

    amin = agrid.min()
    amax = agrid.max()

    for (v0, v1), name in zip([(v_base, v_compare), (v_compare, v_base)],
                              names):

        print('')
        print(name)
        print('')
        print('v0 is larger in {} cases'.format(np.sum(v0 > v1)))
        print('v0 is smaller in {} cases'.format(np.sum(v0 < v1)))

        alist = list()

        for iz in range(v0.shape[1]):

            j, wn = interp(v0[:, iz], v1[ia0, iz], return_wnext=True)

            if j <= -1:
                a = 0.0
            else:
                a = agrid[j] * (1 - wn) + agrid[j + 1] * wn

            a = np.clip(a, amin, amax)

            alist.append(a_mult * a)

        i += 1

        aall.append(np.array(alist))
    return aall[1] - aall[0]