Two Hundred Years of Colombian Economic Growth: The Role of TFP

Using modern growth theory, we estimate Colombian total-factor productivity relative to the United Kingdom’s for the last 200 years in order to match observed income differences. Our results show Colombia’s remarkably inefficient use of technology relative to a country that is a leader in this regard and provide quantitative estimates of the proximate causes of relative income differences between the two economies.Long-run growth, total factor productivity, industrialization, Colombia, relative income differences

Identification of individual demands from market data under uncertainty

We show that, even under incomplete markets, the equilibrium manifold identifies individual demands everywhere in their domains. Under partial observation of the manifold, we determine maximal subsets of the domains on which identification holds. For this, we assume conditions of smoothness, interiority and regularity. It is crucial that there be date-zero consumption. As a by-product, we develop some duality theory under incomplete markets

Global Identification from the equilibrium Manifold under Incomplete markets

We show that even under incomplete markets, the equilibrium manifold identifies individual demands everywhere in their domains. For this, we assume conditions of smoothness, interiority and regularity, but avoid implausible observational requirements. It is crucial that there be date-zero consumption. As a by-product, we develop some duality theory under incomplete marketsIdentification, Incomplete Markets

Global identification from the equilibrium manifold under incomplete markets

We show that even under incomplete markets, the equilibrium manifold identifies individual demands everywhere in their domains. For this, we assume conditions of smoothness, interiority and regularity, but avoid implausible observational requirements. It is crucial that there be date-zero consumption. As a by-product, we develop some duality theory under incomplete marketsIdentification, Incomplete Markets, Duality

THE IDENTIFICATION OF PREFERENCES FROM MARKET DATA UNDER UNCERTAINTY

We show that even under incomplete markets, the equilibrium manifold identifies aggregate demand and individual demands everywhere in their domains. Moreover, under partial observation of the equilibrium manifold, we we construct maximal domains of identification. For this, we assume conditions of smoothness, interiority and regularity, but avoid implausible observational requirements. It is crucial that there be date-zero consumption. As a by-product, we develop some duality theory under incomplete markets.Identification

BELIEF NON-EQUIVALENCE AND FINANCIAL TRADE: A COMMENT ON A RESULT BY ARAUJO AND SANDRONI

Aloisio Araujo and Alvaro Sandroni have shown in [1] that in a complete-markets economy in which there are no exogenous bounds to financial trade, existence of equilibrium requires agents with prior beliefs that agree on zero-probability events, and, therefore, with asymptotically homogeneous posteriors. This note illustrates the extent to which the result depends on market completeness: in general, equilibrium requires compatibility of beliefs only up to the revenue transfer opportunities allowed by the market; when the market is sufficiently incomplete, generically on the space of asset returns, even individuals who disagree on zero-probability events meet that constrained-compatibility" requirement."General equilibrium, heterogeneous beliefs, existence

A derivation of the optimal answer-copying index and some applications

Multiple-choice exams are frequently used as an efficient and objective method to assess learning but they are more vulnerable to answer-copying than tests based on open questions. Several statistical tests (known as indices in the literature) have been proposed to detect cheating; however, to the best of our knowledge they all lack mathematical support that guarantees optimality in any sense. We partially fill this void by deriving the uniform most powerful (UMP) under the assumption that the response distribution is known. In practice, however, we must estimate a behavioral model that yields a response distribution for each question. We calculate the empirical type-I and type-II error rates for several indices that assume different behavioral models using simulations based on real data from twelve nationwide multiple-choice exams taken by 5th and 9th graders in Colombia. We find that the index with the highest power among those studied, subject to the restriction of preserving the type-I error, is one based on the work of Wollack (1997) and Linden and Sotaridona (2006) and is superior to the indices studied and developed by Wesolowsky (2000) and Frary, Tideman, and Watts (1977). We compare the results of applying this index to all 12 exams and find that examination rooms with stricter proctoring have a lower level of copying. Finally, a Bonferroni correction to control for the false positive rate is proposed to detect massive cheating