Dynamics of Inductive Inference in a Unified Framework

We present a model of inductive inference that includes, as special cases, Bayesian reasoning, case-based reasoning, and rule-based reasoning. This unified framework allows us to examine, positively or normatively, how the various modes of inductive inference can be combined and how their relative weights change endogenously. We establish conditions under which an agent who does not know the structure of the data generating process will decrease, over the course of her reasoning, the weight of credence put on Bayesian vs. non-Bayesian reasoning. We show that even random data can make certain theories seem plausible and hence increase the weight of rule-based vs. case-based reasoning, leading the agent in some cases to cycle between being rule-based and case-based. We identify conditions under which minmax regret criteria will not be effective.Induction, Bayesian updating, Case-Based Reasoning, Inference

Reverse Dutch Disease and Mineral Exporting Developing Economies

SUMMARY It is fashionable to refer to the effects of the export booms which most mineral exporting developing economies have experienced at one time or another over the last 20 years as the ‘Dutch Disease’. The original disease had mixed consequences. There are some benefits to be gained from reverse Dutch Disease, the typical problem faced by mineral exporters since the collapse of commodity prices in the 1980s. This article analyses the new opportunities for import substitution which are opened up by reverse Dutch Disease in the context of a long?run specific factors model with mobile capital and an institutionally determined wage. RESUME Le Revers du ‘Mal Hollandais’ et les Economies en voie de Développement, Exportatrices de Minéraux II est très à la mode de faire référence aux effets de la montée en flèche de l'exportation dont la plupart des économies en voie de développement exportant des minéraux ont fait l'expérience à un moment ou à un autre durant les vingts dernières années, sous le nom de ‘Mal Hollandais’. Le malaise initial avait eu des conséquences multiples. L'effet inverse du ‘Mal Hollandais’, problème typique auquel les exportateurs de minéraux ont fait face depuis l'effondrement des prix des marchandises dans les années 1980, peut avoir des avantages. Cet article analyse les nouvelles possibilités offertes par le ‘revers’ du ‘Mal Hollandais’ dans le contexte d'un modèle de facteurs spécifiques à long?terme, avec un capital mobile et des salaires déterminés par les institutions. RESUMEN Reversión dal ‘mal de Holanda’ y economías en desarrollo exportadoras de minerales Esta de moda referirse a los efectos de los auges exportadores que muchas economías en desarrollo, exportadoras de minerales, experimentaron en algún momento durante los últimos años, como al ‘mal de Holanda’. La enfermedad original tiene consecuencias mixtas. Existen algunos beneficios posibles de la reversión del ‘mal de Holanda’, problema típico enfrentado por los exportadores de minerales desde el colapso del precio de los metales en la década de 1980. Este articulo analiza las nuevas oportunidades abiertas por la reversión del ‘mal de Holanda’, para la sustitución de importaciones en el contexto de un modelo específico de factores de largo plazo con capital móvil y un salario determinado institucionalmente

Low cost integrated circuit versatile pulse and frequency counter

Journal ArticleIn this paper we describe a compact multipurpose counter whose design is based on the use of plastic integrated circuits. The circuit contains about $90 worth of semiconductor components and is very easy to wire; nevertheless, it is extremely versatile. It consists of dual 107 and 106 counters which can be used separately as two counters, or in series as a single 101 2 events counter. Frequencies up to 10 MHz can be read to the accuracy of the crystal used (typically better than 0.005%). Time intervals can be measured as either the width of a single pulse or the time interval between the positive (or negative) slopes of two pulses. The circuit can also be used as a digital integrator, since the average count of pulses in a series of numerous pulse train events can be automatically evaluated after 10, 100, 1000, or 10,000 events

Low cost high linearity solid state digital double boxcar

Journal ArticleIn this article, we describe a digital solid state double boxcar of infinite holding time and very high linearity. It uses a Hewlett-Packard (HP2212 A-M3) voltage-to-frequency converter (VFC) whose output is accumulated on a running counter, thereby providing signal averaging with an infinite holding time. The combination of FET signal gates with zero offset and the highly linear VFC results in a linearity of better than ± 0 . 0 1% over an input range of ± 1 . 0 V, which is a considerable improvement over that available with other digital boxcars. Integrated circuit pulse generators of high stability provide gating times from a fraction of a microsecond to many seconds. A unique monitoring system allows ease of adjustment with a simultaneous "master" display of all gating and signal functions. Other features of this boxcar are extreme compactness, low cost, and very high stability

New technique for determining the diffusion mechanism by NMR: application to Cl35 diffusion in TlCl

Journal ArticleA major problem in the study of atomic motions is the determination of the dominant mechanism responsible for translational diffusion. Recently Ailion and Ho predicted that the rotating-frame spin-lattice relaxation time T l p would have an angular dependence which depends on the diffusion mechanism in the ultraslow-motion region. In this paper we have extended these ideas to T1C1 for which the dominant mechanism is known by other experiments to be CI vacancy diffusion. We observed experimentally an angular dependence consistent with the dominant mechanism being CI vacancy diffusion, thereby corroborating the basic ideas of Ailion and Ho. We have also been able to eliminate CI interstitialcy diffusion as a possible dominant mechanism. We measured an activation energy of (0o 733 ± 0 . 012) eV, in agreement with results of other experiments

Self-switching Q-damping circuit for reducing transmitter ringdown time in high power pulse NMR

Journal ArticleIn this paper we describe a circuit for reducing the transmitter ringdown time and thereby improving the recovery time in pulse NMR experiments. The circuit uses only solid state devices and requires no external switching. For transmitter voltages less than 0.5 V peak to peak the effective resistance in parallel with the transmitter coil in a crossed coil spectrometer is only 6 {} whereas for the larger voltages the shunting resistance is of the order of 1-2 {}. This circuit thus has the effect of significantly squaring the envelope of an rf pulse. It has the extra advantage of suppressing noise generated by the transmitter during the time interval between pulses

Frequency modulation method for performing adiabatic demagnetization in the rotating reference frame

Journal ArticleA new method for preforming adiabatic demagnetization in the rotating reference frame in NMR experiments is presented in this paper. In this new method the frequency of a crystal oscillator rather than the actual magnetic field is pulsed off resonance. Using simple circuits which are described in this paper, the effective field in the rotating frame can be pulsed by as much as 50 G, depending on the nucleus studied. This method completely avoids the problem of external magnetic field correction due to a pulsed field in the magnetic gap

Dynamics of Inductive Inference in a Unified Framework

We present a model of inductive inference that includes, as special cases, Bayesian reasoning, case-based reasoning, and rule-based reasoning. This unified framework allows us to examine, positively or normatively, how the various modes of inductive inference can be combined and how their relative weights change endogenously. We establish conditions under which an agent who does not know the structure of the data generating process will decrease, over the course of her reasoning, the weight of credence put on Bayesian vs. non-Bayesian reasoning. We show that even random data can make certain theories seem plausible and hence increase the weight of rule-based vs. case-based reasoning, leading the agent in some cases to cycle between being rule-based and case-based. We identify conditions under which minmax regret criteria will not be effective