Bram De Rock

Married With Children: A Collective Labor Supply Model with Detailed Time Use and Intrahousehold Expenditure Information

We propose a collective labor supply model with household production that generalizes an original model of Blundell, Chiappori and Meghir (2005). In our model, adults’ individual preferences do not only depend on own leisure and individual private consumption of market goods. They also depend on the consumption of domestic goods, which are produced by combining goods bought at the market with individuals’ time. We apply our model to new and unique data on Dutch couples with children. The data contains detailed information about the spouses’ time use and the intrahousehold allocation of all expenditures. Our application uses a novel estimation strategy that builds upon the familiar two-stage allocation representation of the collective model. We obtain interesting (and plausible) empirical results. Spouses’ preferences depend on the consumption of domestically produced goods (including children’s welfare). Next, Pareto weights depend on variables like the individual wages and the share in the household’s nonlabor income. Finally, and perhaps surprisingly, we do not find evidence that mothers care more for their children than fathers.

Opening the Black Box of Intra-Household Decision-Making: Theory and Non-Parametric Empirical Tests of General Collective Consumption Models

We provide “revealed preference” tests of general collective consumption models that account for public consumption and externalities within the household. We further propose a novel approach to model special cases of this model, which imply alternative assumptions regarding the sharing rule. Our application uses the panel data from the Russia Longitudinal Monitoring Survey. We find that the general model, together with a large class of special cases, cannot be rejected. By contrast, we do reject the standard unitary model. Since our tests are entirely nonparametric, this provides strong evidence in favor of models focusing on intrahousehold decision making.

Opening the ‘Black Box’ of Efficiency Measurement – Input Allocation in Multi-Output Settings

We develop a new data envelopment analysis (DEA)-based methodology for measuring the efficiency of decision-making units (DMUs) characterized by multiple inputs and multiple outputs. The distinguishing feature of our method is that it explicitly includes information about output-specific inputs and joint inputs in the efficiency evaluation. This method contributes to opening the “black box” of efficiency measurement in two different ways. First, including information on the input allocation substantially increases the discriminatory power of the efficiency measurement. Second, it allows us to decompose the efficiency value of a DMU into output-specific efficiency values, which facilitates the identification of the outputs the manager should focus on to remedy the observed inefficiency. We demonstrate the usefulness and managerial implications of our methodology by means of a unique data set collected from the activity-based costing (ABC) system of a large service company with 290 DMUs.

Multi-Output Efficiency with Good and Bad Outputs

Cherchye, De Rock, Dierynck, Roodhooft, and Sabbe (2013) introduced a DEA methodology that is specially tailored for multi-output efficiency measurement. The methodology accounts for jointly used inputs and incorporates information on how inputs are allocated to outputs. In this paper, we present extensions that render the methodology useful to deal with undesirable (or “bad”) outputs in addition to desirable (or “good”) outputs. Interestingly, these extensions deal in a natural way with several limitations of existing DEA approaches to treat undesirable outputs. We also demonstrate the practical usefulness of our methodological extensions through an application to US electric utilities.

Analyzing Cost-Efficient Production Behavior Under Economies of Scope: A Nonparametric Methodology

In designing a production model for firms that generate multiple outputs, we take as a starting point that such multioutput production refers to economies of scope, which in turn originate from joint input use and input externalities. We provide a nonparametric characterization of cost-efficient behavior under these conditions, and subsequently institute necessary and sufficient conditions for data consistency with such efficient behavior that only include observed firm demand and supply data. We illustrate our methodology by examining the cost efficiency of research programs in economics and business management faculties of Dutch universities. This application shows that the proposed methodology may entail robust conclusions regarding cost-efficiency differences between universities within specific specialization areas, even when using shadow prices to evaluate the different inputs.

Revealed Preference Analysis of Non‐Cooperative Household Consumption

We develop a revealed preference approach to analyse non-unitary household consumption behaviour that is not cooperative (or Pareto efficient). We derive global necessary and sufficient conditions for data consistency with the model. We show that the conditions can be verified by means of relatively straightforward mixed integer programming methods, which is particularly attractive in view of empirical analysis. Our framework extends to tests for separate spheres and joint contribution to public goods. An application to data drawn from the Russia Longitudinal Monitoring Survey demonstrates the empirical relevance of the non-cooperative consumption model.

Economic Well-Being and Poverty among the Elderly: An Analysis Based on a Collective Consumption Model

An improvement in a contact printer which comprises means for supporting a film and an original in superposed relationship on a vacuum table, means for providing a source of light for exposing the film through the original, and means for moving the light over the surface of the superposed film and original. A substantially impervious, flexible and transparent cover sheet carried by the light moving means is arranged to cover the superposed film and original as the exposing light is scanned across the film and original whereby the vacuum is applied to the film and the original to remove air from therebetween as the film is exposed by the light through the cover sheet and the original. The improvement comprises means for contacting the surface of the cover sheet during use and removing dust and dirt thereon to assure that the optical path for the exposing light remains clear and unobstructed.

Nonparametric analysis of multi-output production with joint inputs

We present a novel framework for analyzing cost minimizing production behavior in multi-output settings. Our specific focus is on dealing with joint inputs, i.e. inputs that are simultaneously used for the production of multiple outputs. Here, we distinguish between two possible approaches. The cooperative approach takes a centralized perspective and assumes cost minimization at the aggregate firm level. By contrast, the noncooperative approach adopts a decentralized view and assumes cost minimization at the level of the individual output departments, which implies the possibility of free riding behavior for the joint inputs. Our framework is non-parametric in nature, which means that it allows for analyzing production behavior while avoiding (nonverifiable) prior functional structure for the production technology. We show that it naturally extends the existing nonparametric framework for analyzing single output production. We establish rationalizability conditions for cooperative as well as noncooperative production behavior. In addition, we introduce goodness-of-fit measures for evaluating the degree of violation of these conditions. An empirical application to the English and Welsh drinking water and sewerage sector shows the practical usefulness of our framework. Specifically, we compare the empirical validity of the cooperative and noncooperative models for describing the observed production behavior.

Goodness-of-Fit Measures for Revealed Preference Tests: Complexity Results and Algorithms

We provide results on the computational complexity of goodness-of-fit measures (i.e., Afriat’s efficiency index, Varian’s efficiency vector-index, and the Houtman-Maks index) associated with several revealed preference axioms (i.e., WARP, SARP, GARP, and HARP). These results explain the computational difficulties that have been observed in literature when computing these indices. Our NP-hardness results are obtained by reductions from the independent set problem. We also show that this reduction can be used to prove that no approximation algorithm achieving a ratio of O(n1 − Δ), Δ ;> 0 exists for Varian’s index, nor for Houtman-Maks’ index (unless P = NP). Finally, we give an exact polynomial-time algorithm for finding Afriat’s efficiency index.

Testable Implications of General Equilibrium Models: An Integer Programming Approach

Focusing on the testable revealed preference restrictions on the equilibrium manifold, we show that the rationalizability problem is NP-complete. Subsequently, we present a mixed integer programming (MIP) approach to characterize the testable implications of general equilibrium models. Attractively, this MIP approach naturally applies to settings with any number of observations and any number of agents. This is in contrast with existing approaches in the literature. We also demonstrate the versatility of our MIP approach in terms of dealing with alternative types of assignable information. Finally, we illustrate our methodology on a data set drawn from the US economy. In this application, an important focus is on the discriminatory power of the rationalizability tests under study. (This abstract was borrowed from another version of this item.)