Unobserved Properties Research Articles

Asymmetric Information and List Price Reductions in the Housing Market

In housing markets with asymmetric information list prices may signal unobserved properties of the house or the seller. Asymmetric information is the starting point of many models for the housing market. In this paper, we estimate the causal effect of list-price reductions to test for the presence of asymmetric information. We use very rich and extensive administrative data from the Netherlands. Our empirical results show that list-price reductions significantly increase the probability of selling a house, but also the rate of withdrawal from the market increases.

The idea of mutual affect

AbstractThe article presents theoretical reasons and research in favor of the idea of mutual affect, describing psychopathological and therapeutic aspects of the affective autoregulation that takes place in intimate relationships. By “affective autoregulation” we refer to the processes of self‐regulation, mutual regulation, and transgenerational regulation of affects, in accordance with different therapeutic models and psychoanalytic theories that emphasize the crucial role of emotions and affects in reducing individual and relational symptomatology and distress. Methods for detecting and studying observable and unobservable properties of affect are presented and discussed through a survey of recent research in the attachment tradition. Some therapeutic implications of this idea, as elaborated and implemented at the Franciscan Family Institute in Ljubljana, are also presented. Copyright © 2006 John Wiley & Sons, Ltd.

Theory-based Bayesian models of inductive learning and reasoning

Inductive inference allows humans to make powerful generalizations from sparse data when learning about word meanings, unobserved properties, causal relationships, and many other aspects of the world. Traditional accounts of induction emphasize either the power of statistical learning, or the importance of strong constraints from structured domain knowledge, intuitive theories or schemas. We argue that both components are necessary to explain the nature, use and acquisition of human knowledge, and we introduce a theory-based Bayesian framework for modeling inductive learning and reasoning as statistical inferences over structured knowledge representations.

The Costs of Urban Property Crime

This paper estimates the impact of recorded domestic property crime on property prices in the London area. Crimes in the Criminal Damage category have a significant negative impact on prices. A one-tenth standard deviation decrease in the local density of criminal damage adds 1% to the price of an average Inner London property. Burglaries have no measurable impact on prices, even after allowing for the potential dependence of burglary rates on unobserved property characteristics. One explanation we offer here is that vandalism, graffiti and other forms of criminal damage motivate fear of crime in the community and may be taken as signals or symptoms of community instability and neighbourhood deterioration in general. 1. Crime in Cities and the Demand for Low-crime Spaces

Preschoolers Are Sensitive to the Speaker’s Knowledge When Learning Proper Names

Unobservable properties that are specific to individuals, such as their proper names, can only be known by people who are familiar with those individuals. Do young children utilize this "familiarity principle" when learning language? Experiment 1 tested whether forty-eight 2- to 4-year-old children were able to determine the referent of a proper name such as "Jessie" based on the knowledge that the speaker was familiar with one individual but unfamiliar with the other. Even 2-year-olds successfully identified Jessie as the individual with whom the speaker was familiar. Experiment 2 examined whether children appreciate this principle at a general level, as do adults, or whether this knowledge may be specific to certain word-learning situations. To test this, forty-eight 3- to 5-year-old children were given the converse of the task in Experiment 1--they were asked to determine the individual with whom the speaker was familiar based on the speaker's knowledge of an individual's proper name. Only 5-year-olds reliably succeeded at this task, suggesting that a general understanding of the familiarity principle is a relatively late developmental accomplishment.

Overview of Grain Models

The properties of interstellar grains can now be defined by a rapidly growing wealth of observational data. We rely upon models to combine these data with unobserved properties such as the size distribution of grains, their structure and shape, and their detailed chemical composition, in a self-consistent manner. I will review the observational constraints which define the boundaries for possible models and will then summarize the features of the three quasi-comprehensive grain models most commonly referred to in the current literature. I will conclude by discussing recent work dealing with single aspects of interstellar grains and the phenomena attributed to them.

Universality and conformal invariance for the Ising model in domains with boundary

The partition function with boundary conditions for various two-dimensional Ising models is examined and previously unobserved properties of nonformal invariance and universality are established numerically.

A theory of information with special application to search problems.

Classical information theory concerns itself with communication through a noisy channel and how much one can infer about the channel input from a knowledge of the channel output. Because the channel is noisy the input and output are only related statistically and the rate of information transmission is a statistical concept with little meaning for the individual symbol used in transmission. Here we develop a more intuitive notion of information that is concerned with asking the right questions--that is, with finding those questions whose answer conveys the most information. We call this confirmatory information. In the first part of the paper we develop the general theory, show how it relates to classical information theory, and how in the special case of search problems it allows us to quantify the efficacy of information transmission regarding individual events. That is, confirmatory information measures how well a search for items having certain observable properties retrieves items having some unobserved property of interest. Thus confirmatory information facilitates a useful analysis of search problems and contrasts with classical information theory, which quantifies the efficiency of information transmission but is indifferent to the nature of the particular information being transmitted. The last part of the paper presents several examples where confirmatory information is used to quantify protein structural properties in a search setting.

A theory of information with special application to search problems

Classical information theory concerns itself with communication through a noisy channel and how much one can infer about the channel input from a knowledge of the channel output. Because the channel is noisy the input and output are only related statistically and the rate of information transmission is a statistical concept with little meaning for the individual symbol used in transmission. Here we develop a more intuitive notion of information that is concerned with asking the right questions—that is, with finding those questions whose answer conveys the most information. We call this confirmatory information. In the first part of the paper we develop the general theory, show how it relates to classical information theory, and how in the special case of search problems it allows us to quantify the efficacy of information transmission regarding individual events. That is, confirmatory information measures how well a search for items having certain observable properties retrieves items having some unobserved property of interest. Thus confirmatory information facilitates a useful analysis of search problems and contrasts with classical information theory, which quantifies the efficiency of information transmission but is indifferent to the nature of the particular information being transmitted. The last part of the paper presents several examples where confirmatory information is used to quantify protein structural properties in a search setting.

On the Sternfeld-Levin counterexamples to a conjecture of Chogoshvili-Pontrjagin

An inconclusive proof in a 1937 paper by G. Chogoshvili spawned an interesting dimensiontheoretic conjecture which we call the Chogoshvili-Pontrjagin Conjecture. In 1991, Y. Sternfeld found an ingenious counterexample to this conjecture which he and M. Levin greatly generalized in 1995. In this note we point out a previously unobserved property of the Sternfeld-Levin examples, and we reinterpret their significance in light of this property. Also, we present a version of the Levin-Sternfeld proof which is more “topological” and less “lattice-theoretic” than the original.

Photoinduced conversion of optically active defects in germanium-doped silica

Optical absorption, photoluminescence (PL), and electron paramagnetic resonance (EPR) data on unirradiated and UV-irradiated Ge-doped silica are reported. The analysis of the UV-induced effects shows the following facts: (i) both components of the 5-eV absorption band are partially bleached, as well as the PL excited within this absorption band; (ii) more consistent UV-induced changes arise at higher energies where bands at 5.8 and 6.4 eV grow during the treatment; (iii) Ge-E\ensuremath{'} and Si-E\ensuremath{'} EPR centers are UV generated, confirming their involvement in the photoconversion process but ruling out previous attribution of the 6.4 eV to Ge-E\ensuremath{'} centers; and (iv) the absorption band at 6.4 eV shows previously unobserved emission properties, probably due to excitation transfer processes. \textcopyright{} 1996 The American Physical Society.

Teacher’s Corner: Negative Information and The Three-Parameter Logistic Model

The 3-parameter logistic model is commonly used to describe the relationship among an unobserved latent trait (ability), unobserved item properties, and an observed binary outcome. We show that for certain values of the item properties and latent ability, the observed information about ability contained in the binary response is negative. This result has implications for maximization procedures, such as Newton-Raphson; approximate sampling methods, such as the Metropolis-Hastings algorithm; and Bayesian adaptive testing. All of these typically utilize the observed information. This result is contrasted with the fact that observed negative information does not occur in the limiting case with no guessing (2-parameter logistic model). The probability of negative information is expressed by a simple formula. This research extends the work of Samejima (1973) and Yen, Burket, and Sykes (1991).

The Born-Einstein debate: Where application and explanation separate

Application in science has its own structure, distinct from the structure of theoretical science, and therefore needs its own philosophy. The covering power of a formal scientific theory is no guide to its explanatory power. Explanation is too much to ask of a fundamental scientific theory. This is seen by considering two strands of the Born-Einstein debate: first the explanatory power of quantum mechanics and second, the reality of unobserved properties. The function of theoretical physics is to describe rather than to explain. Some techniques are a standard part of theory; while some aread hoc to the problems at hand. Very few of the derivations in mathematical physics are explanatory. This shows distinctly separate structures for theory and for application.

Solar Neutrinos: Questions and Hypotheses

The "solar neutrino puzzle" has been a challenge for almost 20 years, posing broad and fundamental questions about astrophysics and neutrino properties. This article sketches some of the ideas that have been put forward to solve the problem. These ideas can be grouped into two main classes: those involving changes in the standard solar model or in the basic nuclear reaction data, and those that attribute the puzzle to as yet unobserved properties of the neutrinos.

Unusual behavior of isocyanate and halide complexes of copper(II)

Tetracyanato and tetrahalo complexes of copper(II) show interesting and heretofore unobserved properties in both the solid state and in various non-aqueous media. Various salts of the isocyanato and halocuprate(II) anion involving tetraethylammonium and other bulky cations were prepared. In the cases of tetraphenylphosphonium and tetraphenylarsonium salts of the tetraisocyanatocuprate(II) anion, geometric isomers (blue and yellow) were isolated from alcohol-water solutions of cupric nitrate, potassium cyanate, and tetraphenylphosphonium chloride or tetraphenylarsonium chloride upon evaporation at room temperature. All the tetraisocyanatocuprate(II) salts yielded greenish-yellow solutions when dissolved at room temperature in chloroform, dichloromethane, nitromethane, or acetone which became bright yellow when warmed and generally developed a blue color when cooled to dry ice temperature. Absorption spectra of these solutions from 320 to 1000 mμ were studied from −55°C to +45°C, and reflectance and infrared absorption spectra of the various solid compounds were recorded. Magnetic moments, obtained by the Gouy method, revealed that the blue and yellow forms of the tetraphenylphosphonium and tetraphenylarsonium tetraisocyanatocuprate(II) salts were distinctly different species of identical composition. It is proposed that the four NCO entities are arrayed about the copper in a square planar (or pseudo octahedral) manner in the blue isomer and in a tetrahedral (though probably distorted) fashion in the yellow form.

On an hitherto unobserved property of chlorine

"On an hitherto unobserved property of chlorine." The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, 3(13), p. 72