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Semiparametric Estimation of Random Coefficients in Structural Economic Models Stefan Hoderlein 1 Lars Nesheim 2 Anna Simoni 3 1 Boston College 2 CeMMAP, UCL and IFS 3 Universit Bocconi MIT May 28, 2011. Hoderlein - Nesheim - Simoni (CeMMAP)


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Semiparametric Estimation of Random Coefficients in Structural Economic Models

Stefan Hoderlein1 Lars Nesheim2 Anna Simoni3

1Boston College 2CeMMAP, UCL and IFS 3Università Bocconi

MIT May 28, 2011.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 1 / 43

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Motivation

Heterogeneous population is characterized by the following first order condition ∂cu(ct, γ) = βE [Rt+1∂avt(Wt+1, Zt+1, θ)|Wt, Zt] (1) where ct is consumption, Rt+1 is the interest rate, (Wt, Zt) are state variables, θ = (β, γ) is a finite dimensional parameter vector, and (u, vt) are known functions.

e.g., a CRRA utility function and the corresponding value function.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 2 / 43

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Question

Solution of (1) implicitly defines consumption function c = ϕ (w, z, θ) . Suppose ϕ is known. Suppose data on (Ct|Wt, Zt) are generated from composition of ϕ and an unknown distribution fθ|W .

  • Question. Given data and knowledge of ϕ, can one identify and

estimate fθ|W nonparametrically?

Knowledge of ϕ and fθ|W necessary to predict distribution of impacts of counterfactual changes in interest rates, income tax, pension and savings policy, etc. Economic theory provides information/structure on ϕ; does not have much power to constrain fθ|W . In general, economic logic implies θ and W are correlated.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 3 / 43

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Answer

Answer: We show that:

For Zt exogenous, fCt|WtZt = Tg fθ|W where Tg is an integral operator. The identified set is the set of solutions of the previous equation that are densities. Estimation can be based on regularization of the pseudo-inverse of Tg and computation of null space of Tg .

In Euler equation case, can be much more flexible about ϕ. Our approach applies to general non-separable structural models

  • f the form

Ψ (C, W , Z, θ, ε) = 0.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 4 / 43

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Literature I

Nonparametric Random Coefficient Models: Beran, Hall, Feuerverger (1994), Hoderlein, Klemela, Mammen (2004, 2009), Gautier and Kitamura (2010), Hoderlein (2010). Nonparametric IV Models: Florens (2002), Darolles, Florens, Renault (2002), Newey and Powell (2003), Hall and Horowitz (2005), Blundell, Chen, Kristensen (2007).... Identification in Nonlinear Random Coefficient Models: Bajari, Fox, Kim and Ryan (2009), Fox and Gandhi (2010)

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 5 / 43

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Literature

Mixture Models: Heckman and Singer (1984), Henry, Kitamura, Salanie (2010), Kasahara and Shimotsu (2009), Bonhomme (2010). Parametric Consumption Models: Deaton (1992), Alan and Browning (2009), Blundell, Browning and Meghir (1994), Browning and Lusardi (1996), Attanasio and Weber (2010), Gourinchas and Parker (2002)...

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 6 / 43

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Contributions relative to literature I

Identification in Nonlinear Random Coefficient Models

Provide general identification results using different assumptions (continuum of types vs. finite number). Provide formal statement of difficulty of identification making use of inverse problem literature. Introduce regularization bias to make estimation feasible and provide large sample theory. Make clear how results relate to economic features of the model and provide additional insights about source of identification.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 7 / 43

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Contributions relative to literature II

Parametric Consumption Models

Most of literature allows either for no heterogeneity or only observed heterogeneity. We focus on quite flexible unobserved heterogeneity. Alan and Browning (2010): Nonparametric vs parametric. Provide results on identification.

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Contributions relative to literature III

Relative to Nonparametric Random Coefficient Models:

Extends work of Beran et al.(1994), Hoderlein et al.(2009), Gautier and Kitamura (2010) to general non-separable models.

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Contributions relative to literature IV

Relative to Nonparametric IV Models:

Very different objects of interest. Very close in terms of tools.

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Contributions relative to literature V

Relative to Mixture Models:

Very different models. Similarity: estimating equation fY (y) =

  • fY |θ(y; θ)fθ(θ)dθ.

Heckman and Singer (1984), fY |θ(y; θ) = fY |θ(y; θ, σ) parametric with finite parameter of interest σ, fθ nuisance parameter. Henry, Kitamura, Salanie (2010), Bonhomme (2010) same objective as HS, nonparametric extension, place finite mixture structure on fθ. We: fθ parameter of interest, structure e.g. through CRRA model on fY |θ.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 11 / 43

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General model

Assumption 1. (Structural Model). The random variables (C, W , Z, θ, ε) satisfy Φ(C, W , Z, θ, ε) = 0 almost surely (2) where Φ is a Borel measureable function. In addition, equation (2) has a unique solution in C implicitly defining the Borel measureable consumption function C = ϕ(W , Z, θ, ε). C is an outcome variable; C ∈ R, observed. W are endogenous variables; W ∈ Rk, observed. Z are exogenous variables; Z ∈ Rl, observed. θ are random parameters; θ ∈ Rd, unobserved. ε is a random scalar, not of primary interest; ε ∈ R unobserved:

measurement error unobserved state variable.

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Euler equation example

In the Euler equation example,

C is consumption, W is assets and lagged income, Z is current labor income, ε is private information about future income, and θ are parameters that represent heterogeneity in preferences or beliefs.

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Differentiability

Assumption 2. (Differentiability). Ψ is C1 in a neighborhood of the set of solutions of (2) and ∂cΨ (c, w, z, θ, ε) = ∂εΨ (c, w, z, θ, ε) = almost everywhere on the solution set of (2) .

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Dependence conditions

Assumption 3.(Distribution of ε). The variable ε has a known continuous distribution conditional on (θ, W , Z) with Radon-Nikodym derivative fε|θWZ . Assumption 4. (Conditional independence of Z). The variables (C, Z, θ|W ) have a joint continuous distribution and Z ⊥ ⊥ θ| W .

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 15 / 43

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Support conditions

Assumption 5. The densities fC |WZ and fθ|W are strictly positive and bounded on their supports for almost every (W , Z). The support of fθ|W does not depend on W .

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Example 1

Finite horizon Euler equation with CARA utility. Given assets at, income zt and a shock to permanent income εt , consumer chooses consumption ct. Consumer’s value function defined by vt(at, zt, εt) = max

{ct}

       − e−γct

γ

+ βE[vt+1(at+1, zt+1, εt+1, θ)|zt] subject to at+1 = R(at − ct) zt+1 = zt + εt + νt+1        where

εt ∼ N

  • 0, σ2

ε

  • , νt ∼ N
  • 0, σ2

η

  • ,

εt ⊥ ⊥ νt and (εt, νt, z0) ⊥ ⊥ (θ, a0) , and θ = (β, γ) .

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Consumption function I

Optimal consumption function takes the form: ct = φ1tat + φ2t(zt + εt) + Mt(γ, β) where Mt (β, γ) = φ3t (ln β + ln R) γ + φ4t + 0.5φ5tγ. (3) Trivial but illuminating example. at and θ = (β, γ) statistically dependent because at determined by past savings decisions.

Dependence changes with age.

Income process is independent of preferences. Defining Wt = (At, Zt−1) , this implies Zt ⊥ ⊥ θ| Wt.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 18 / 43

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Consumption function II

Innovations to income Zt move consumption around through known function ϕ. These movements are independent of θ.

In this example, due to linearity, this is not very helpful. More generally, ϕt is not additively separable (non-normal disturbances, CRRA utility, stochastic interest rates).

(β, γ) affect outcome only through single index m = Mt (β, γ) .

Joint distribution of (β, γ)| W not point-identified but distribution of Mt| Wt is. Stochastic variation in interest rates, can point-identify joint distribution.

Estimation method can be applied to a more general Euler equation model.

See Hoderlein, Nesheim and Simoni (2011).

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Notation

Let (πθ, πcz) be nonnegative weighting functions on spt (Θ) and spt (C × Z) respectively. Consider the spaces L2

πθ =

  h :

  • Θ

h(θ, w)2πθdθ < ∞, PW − a.e.    and L2

πcz =

  ψ :

  • C×Z

ψ(c, z, w)2πczdcdz < ∞, PW − a.e.    . Let Fθ|W ⊂ L2

πθ and FC |WZ ⊂ L2 πcz be the subsets of densities on Θ

and conditional densities on C × Z that are strictly positive and bounded on their supports.

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Characterization of fθ|W

Theorem (1.i.)

Let fC |WZ ∈ FC |WZ ⊂ L2

πcz . Under Assumptions 1-5, fθ|W is a solution of

the nonlinear problem fC |WZ = Tgfθ|W subject to fθ|W ∈ FC |WZ PW − a.s. (4) where Tg : L2

πθ → L2 πcz is defined for all h ∈ L2 πθ as

(Tgh) (c, w, z) =

  • θ

fC |WZ θ(c, w, z, θ) πθ h(θ, w)πθdθ. (5) Kernel of operator is g (c, w, z, θ) = fC |WZ θ (c, w, z, θ) πθ = ∑s

i=1 fε|θWZ

  • ϕ−1

i

, θ, w, z

  • ∂c Ψ(c,w ,z,θ,ϕ−1

i

) ∂εΨ(c,w ,z,θ,ϕ−1

i

)

  • πθ

1sptC |WZ θ where 1spt denotes support of C|WZθ and s is number of

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Comments

Equation (5) is classical mixture of probability densities or Fredholm integral of the first kind. If fC |WZ θ ≡ f (c − θ, w, z) we recover the convolution formula. If Fε is degenerate with a point mass only at ε = 0, can define the

  • perator as

(Tgh) (c, z, w) =

  • Θ

1 {ϕ (w, z, θ) ≤ c} h(θ, W )dθ. Simple inversion of Tg does not work since R(Tg ) is non-closed and in general ˆ fC |WZ / ∈ R(Tg ). Pseudo-inverse T †

g is also unbounded.

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Hilbert-Schmidt

Assumption 6. It is possible to choose πθ and πcz such that for PW -a.e. w we have:

  • C×Z
  • Θ
  • fC |WZ θ(c; w, z, θ)

2 πcz πθ dcdzdθ < ∞. Hilbert-Schmidt assumption is sufficient to guarantee the compactness of Tg. Compact operator Tg has at most a countable number of singular values accumulating only at 0. Let

  • λj, ϕj, ψj

j=1 be the SVD of Tg.

How fast λj ↓ 0 depends on smoothness of Tg.

This determined by smoothness of Ψ, distribution of ε and the support

  • f (C, Z, θ) .

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Identification I

Theorem (1.ii.)

Under Assumptions 1-5, a solution of (4) exists since fC |WZ ∈ Tg Fθ|W . The identified set is Λ = {h ∈ Fθ|W : Tgh = fC |WZ , PW a.e.} =

  • f †

θ|W ⊕ N (Tg )

  • ∩ Fθ|W

=          h ∈ L2

πθ :

h = f †

θ|W + ∑j≥1;λj=0 zj ϕj for some {zj}

h > 0

  • Θ

h = 1          where f †

θ|W is the solution of minimal norm of

  • Tgh − fC |WZ
  • and ϕj are

the eigenfunctions of T ∗

g Tg corresponding to the zero eigenvalues λj.

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Identification II

Three situations are possible:

1

Tg one-to-one: N (Tg ) = {0} ⇒ f †

θ|W ∈ Fθ|W .

2

Tg one-to-one on Fθ|W ⇒

  • f †

θ|W ⊕ N (Tg )

  • ∩ Fθ|W = {f †

θ|W }.

3

Tg not one-to-one on Fθ|W ⇒ many possible values of {z1, z2, . . .}.

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Identification III

Theorem (2.)

Under Assumptions 1-5, the following are equivalent sufficient conditions for point identification of fθ|W .

1

The operator Tg is one-to-one. i.e. N (Tg ) = {0}.

2

The distribution of θ conditional on (C, W , Z) is complete.

3 ∀(c, z) ∈ C × Z,

fC |WZ θ(c;w ,z,θ) πθ(θ)

belongs to a complete subset C in L2

πθ, PW − a.s.

i.e. the only element in L2

πθ which is orthogonal to C is 0.

4 R(T ∗

g ) is dense in L2 πθ, i.e. R(T ∗ g ) = L2 πθ.

5

If Assumption 6 holds, the singular values of Tg are strictly positive.

i.e. λj > 0 for all j.

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Discussion

In this case, the inverse T −1

g

exists and fθ|W (θ; w) = T −1

g

fC |WZ (c; w, z), PW − a.e. Properties of the operator Tg (like smoothness) are determined by smoothness properties of ϕ and fε. Identified set is smaller than the identified set of the equation Tgh = fC |WZ . Point-identification requires dim(C, Z) ≥ dim(θ).

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Identification IV

Sufficient condition for point-identification of fθ|W . Lemma 3.1: Assume that fC |θWZ (c, θ, w, z) takes the form exp

  • τ(c, w, z)T m(θ)
  • k(c, w, z)h(θ)

where spt (τ (C, W , Z)) = Rd, h(·) is a positive function, and m is globally invertible. Then, fθ|W is point-identified. Note exponential interactions between m (θ) and τ (c, w, z) and support condition.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 28 / 43

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Example 1: Identification I

Operator equation is fC |WZ (c, w, z) =

  • Θ

exp(− 1

2( c−φ1w −M(β,γ)−z φ2σε

)2)

  • 2πφ2

2σ2 ε

fβγ|W (β, γ, w)dβdγ. (6) Joint density of (β, γ) not point identified. To see this, use m = M (β, γ) to make change of variables.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 29 / 43

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Example 1: Identification II

Change of variables implies fC |WZ (c, w, z) =

  • M
  • Γ

exp(− 1

2( c−φ1w −m−z φ2σε

)2)

  • 2πφ2

2σ2 ε

  • fMγ|W (m, γ, w)dmdγ

(7) =

  • M

exp(− 1

2( c−φ1w −m−z φ2σε

)2)

  • 2πφ2

2σ2 ε

  • fM|W (m, w)dm

where

  • fMγ|W (m, γ, w) = fβγ|W (M−1(m, γ), γ)
  • ∂M−1(m, γ)

∂m

  • .

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Example 1: Identification III

Conditional on M, γ has no impact on consumption.

No interactions between (C, Z) and γ.

Nevertheless, marginal density fM|W is point-identified. To see this, use Lemma 3.1 framework and note τ (c, w, z) = c − φ1w − z φ2σε h (θ) = exp

  • −1

2 m (θ) φ2σε 2 k (c, w, z) = exp

  • − 1

2

c−φ1w −z

φ2σε

2

  • 2πφ2

2σ2 ε

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Example 1: Identification IV

Identified set of densities fβγ|W is the set

  • h : h =

fM|W fγ|MW ·

  • ∂M

∂γ

  • for some

fγ|MW ∈ Fγ|MW

  • .

Null space of operator is N (Tg ) = {h : h1 (m) · ∆h2 (γ |m)} wheres h1 solves (7) and ∆h2 is the difference between two arbitrary conditional densities. Data provide no restrictions on conditional density; other than support restrictions. Nevertheless, data do provide some restrictions on the joint density. See simulation results to follow. First, how do we estimate the model?

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Estimation I

1

First estimate fC |WZ .

2

Then solve constrained problem min

{h}

  • Tgh −

fC |WZ

  • + α h2

s

subject to h ≥

  • Θ

h (θ, w) dθ = 1.

1

Paper contains results for case where f †

θ|W /

∈ Fθ|W , (solve the constrained minimization numerically, no closed-form for the estimator and slower rate of convergence).

2

Here, assume f †

θ|W ∈ Fθ|W .

3

Ill-posed inverse problem. Regularization required because T †

g is

unbounded.

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Estimation II

1

Two-step procedure to solve problem.

1

Compute f α,s

θ|W to solve

min

{h}

  • Tg h −

fC |WZ

  • + α h2

s .

2

Compute projection Πc f α,s

θ|W = max

  • 0,

f α,s

θ|W − c

πθ

  • where c satisfies
  • Θ

Πc f α,s

θ|W dθ = 1.

1

Algorithm by Gajek (1986).

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Estimation of fθ|W

Assumption 7. {ci, wi, zi}N

i=1 is an i.i.d. sample used to construct an

estimator f N

C |WZ of fC |WZ such that

lim

N→∞ E

  • f N

C |WZ − fC |WZ

  • 2

= 0.

1

First replace fC |WZ with a (nonparametric) estimator ˆ fC |WZ .

Kernel density estimator.

2

Second, compute regularized version of T †

g .

Tikhonov regularization (ˆ f α

θ|W (θ; w)).

Tikhonov regularization in Hilbert scales (generalized Tikhonov).

3

Third, project onto space of densities.

4

Finally, compute eigenfunctions of null space. Alternatively, replace steps 2. and 3. with one-step constrained minimization.

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Rate of convergence I

Assumption 8. For some β > 0 and 0 < M < ∞ the structural density f †

θ|W is an element of the β-regularity space Φβ(M) defined as

Φβ(M) =

  • f ∈ N (Tg )⊥;

j

< f , ϕj >2 λ2β

j

< M

  • .

Smoothness condition. f †

θ|W is more smooth when β is larger.

When M = ∞ then, Φβ = R[(T ∗

g Tg )

β 2 ]. Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 36 / 43

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Rate of convergence II

Theorem

Given Assumptions 1-5 and 8, the MISE associated with Pc ˆ f α

θ|W with

s = 0 is E

  • Pc ˆ

f α

θ|W − f †c θ|W

  • 2

= O

  • αβ∧2 + 1

αE

  • ˆ

fC |WZ − fC |WZ

  • 2

. Moreover, if α (E

  • ˆ

fC |WZ − fC |WZ

  • 2)−

1 β∧2+1 then,

E

  • Pc ˆ

f α

θ|W − f †c θ|W

  • 2

= O

  • E
  • ˆ

fC |WZ − fC |WZ

  • 2

β∧2 β∧2+1

  • .

For s = 0, there is no benefit from β > 2. In the paper, we present analysis of rates of convergence using regularization for s > 0 (Hilbert scales).

When f †

θ|W is highly smooth, these have faster rates of convergence.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 37 / 43

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Rates of convergence III

Suppose fC |WZ is estimated as ˆ fC |WZ (c; w, z) =

1 nh1+k+l ∑n i=1 Kh(ci − c, c)Kh(wi − w, w)Kh(zi − z, z) 1 nhk+l ∑n l=1 Kh(wl − w, w)Kh(zl − z, z)

. (8) where Kh is a (generalised) kernel of order r and h is a vector of bandwidths. Under mild regularity conditions on the kernel and the operator Tg, the optimal rate of the Tikhonov estimator is inf

α,h E||ˆ

f α

θ|W − f † θ|W ||2 n−

2ρ(β∧2) (2ρ+k)(β∧2+1)

where

ρ is the number of derivatives in W of fC |WZ . Optimal values of α and h are: h n−

1 2ρ+k and α n− 2ρ (2ρ+k)(β∧2+1) .

Curse of dimensionality only in the dimension of the endogenous variables W .

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 38 / 43

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Pointwise asymptotic normality

Lemma (pointwise asymptotic normality): Let ˆ f α

θ|W be the Tikhonov

regularized estimator described above. If α n−

2ǫρ (2ρ+k)(β∧2+1) for ǫ > 1 and

h n−

1 2ρ+k +εh, εh < 0, then (under mild assumptions) for PW -a.e. W

√ nhk ˆ f α

θ|W (θ, w) − f † θ|W (θ, w)

Ω(θ, w) ⇒ N (0, 1) where Ω(θ, w) =

j=1

λ2

j

(α + λ2

j )2 Ω1 (j) ϕ2 j + 2 ∞

j<l

λjλl (α + λ2

j )(α + λ2 l )Ω2 (j, l) ϕj ϕl.

Require α and h to converge faster than optimal to guarantee asymptotic bias of ˆ f α

θ|W (θ; w) is negligible.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 39 / 43

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Estimation of Example 1

Simulate data from CARA model. Estimate and plot the PDF of M |W . Estimate and plot the CDF of M |W . Display implications for identified set for (β, γ) .

Using m = M (β, γ) , plot level sets of M. For each u ∈ [0, 1] , plot "quantile level sets" such as Pr (M (β, γ) ≤ m) = u.

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 40 / 43

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SLIDE 41

Simulated data

20 30 40 50 60 70 80 2 4 6 8 10 12 14 16

Ag e I n c

  • m

e Qu a n ti le s o f in c o m e 0 .2 5 0 .5 0 0 .7 5

20 30 40 50 60 70 80

  • 2

2 4 6 8 10 12 14 16 18

Ag e C

  • n

s u m p t i

  • n

Qu a n ti le s o f c o n s u m p tio n 0 .2 5 0 .5 0 0 .7 5

20 30 40 50 60 70 80

  • 10

10 20 30 40 50 60 70

Ag e A s s e t s Qu a n tile s o f a s s e ts 0 .2 5 0 .5 0 0 .7 5

  • 0. 9
  • 0. 91
  • 0. 92
  • 0. 93
  • 0. 94
  • 0. 95
  • 0. 96
  • 0. 97
  • 0. 98
  • 0. 99

1

  • 0. 5

1

  • 1. 5

2

  • 2. 5

3

  • 3. 5

4

β γ Sc a tte r p lo t o f β a n dγ

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 41 / 43

slide-42
SLIDE 42

Example 1: Estimation I

  • 7
  • 6
  • 5
  • 4
  • 3
  • 2
  • 1

1 2 3

  • 0. 1
  • 0. 2
  • 0. 3
  • 0. 4
  • 0. 5
  • 0. 6
  • 0. 7
  • 0. 8
  • 0. 9

1

θ D e n s i t y

  • f

θ M L E (c o n d itio n a l o n w = -0 .7 9 0 8 9

K er nel M LE Ti khonov

  • 7
  • 6
  • 5
  • 4
  • 3
  • 2
  • 1

1 2 3

  • 0. 2
  • 0. 4
  • 0. 6
  • 0. 8

1

  • 1. 2
  • 1. 4

θ D e n s i t y

  • f

θ M L E (c o n d itio n a l o n w = -0 .3 6 2 1 9

K er nel M LE Ti khonov

  • 7
  • 6
  • 5
  • 4
  • 3
  • 2
  • 1

1 2 3

  • 0. 2
  • 0. 4
  • 0. 6
  • 0. 8

1

  • 1. 2
  • 1. 4

θ D e n s i t y

  • f

θ M L E (c o n d itio n a l o n w = 0 .5 2 5 0 7

K er nel M LE Ti khonov

  • 7
  • 6
  • 5
  • 4
  • 3
  • 2
  • 1

1 2 3

  • 0. 2
  • 0. 4
  • 0. 6
  • 0. 8

1

  • 1. 2
  • 1. 4

θ D e n s i t y

  • f

θ M L E (c o n d itio n a l o n w = 0 .7 3 4 6 2

K er nel M LE Ti khonov

slide-43
SLIDE 43

Example 1: Estimation II

  • 0. 5

1

  • 1. 5

2

  • 2. 5

3

  • 3. 5

4

  • 1. 8
  • 1. 6
  • 1. 4
  • 1. 2
  • 1
  • 0. 8
  • 0. 6
  • 0. 4
  • 0. 2

Qu a n tile s e ts o f θ = M ( γ,lo g ( β)) c o n d i tio n a l o n w = -0 .7 9 0 8 9 γ l

  • g

( β ) 0 .1 -q u a n tile o f θ 0 .4 -q u a n tile o f θ 0 .6 -q u a n tile o f θ 0 .9 -q u a n tile o f θ

  • 0. 5

1

  • 1. 5

2

  • 2. 5

3

  • 3. 5

4

  • 0. 9
  • 0. 8
  • 0. 7
  • 0. 6
  • 0. 5
  • 0. 4
  • 0. 3
  • 0. 2
  • 0. 1

Qu a n tile s e ts o f θ = M ( γ,lo g ( β)) c o n d i tio n a l o n w = -0 .3 6 2 1 9 γ l

  • g

( β ) 0 .1 -q u a n tile o f θ 0 .4 -q u a n tile o f θ 0 .6 -q u a n tile o f θ 0 .9 -q u a n tile o f θ

  • 0. 5

1

  • 1. 5

2

  • 2. 5

3

  • 3. 5

4

  • 0. 4
  • 0. 35
  • 0. 3
  • 0. 25
  • 0. 2
  • 0. 15
  • 0. 1
  • 0. 05

Qu a n tile s e ts o f θ = M ( γ,lo g ( β)) c o n d itio n a l o n w = 0 .5 2 5 0 7 γ l

  • g

( β ) 0 .1 -q u a n tile o f θ 0 .4 -q u a n tile o f θ 0 .6 -q u a n tile o f θ 0 .9 -q u a n tile o f θ

  • 0. 5

1

  • 1. 5

2

  • 2. 5

3

  • 3. 5

4

  • 0. 35
  • 0. 3
  • 0. 25
  • 0. 2
  • 0. 15
  • 0. 1
  • 0. 05

Qu a n tile s e ts o f θ = M ( γ,lo g ( β)) c o n d itio n a l o n w = 0 .7 3 4 6 2 γ l

  • g

( β ) 0 .1 -q u a n tile o f θ 0 .4 -q u a n tile o f θ 0 .6 -q u a n tile o f θ 0 .9 -q u a n tile o f θ

Hoderlein - Nesheim - Simoni (CeMMAP) Semiparametric Random Coefficients May 28, 2011 43 / 43