La Permuta: an effective instrument for housing transactions in Cuba

This paper is about the permuta, which is the only legal instrument created by the Cuban authorities to facilitate land and housing exchanges. Beyond that fact, the permuta has sociological and economical significance as being the escape valve for the people in their resistance to being standard people in standard housing,i as it reflects the increasing demand of families for more diversified dwelling options. In the absence of a formal real estate market, the permuta has proved very effective in incorporating hidden and informal valuations and transactions in housing, where monetary interests are increasingly appearing as an important feature. Over the last decades, the number of arrangements and agreements between the parties, and the complexity of the negotiations has increased. The transactions within the permuta now incorporate new aspects that anticipate future value increments and other benefits and profits from the development of home based businesses, or that anticipate positive impacts derived from public investments or new urban regulations. The study of the permuta is therefore very attractive for urban planners and economists. But the study is also difficult for various reasons: it is very vulnerable to legal and institutional changes, it has a dual (legal and illegal) connotation, it has a large capacity to mutate and camouflage in order to evade restrictions, and there are no trustworthy records of the informal transactions

Proyecto constructivo de aparcamiento subterráneo en la Calle Jacint Verdaguer de Sant Joan Despí

El presente proyecto tiene como objeto definir y valorar las obras necesarias para la construcción de un aparcamiento subterráneo en la Calle Jacint Verdaguder de Sant Joan Despí, mediante ejecución de contrato de permuta entre la propiedad de la parcela (Església Parroquial de Sant Joan Baptista, en adelante EPSB) y el contratista de la obra. El contrato de permuta consiste en la cesión del terreno por parte de EPSB, la construcción del aparcamiento por parte del contratista, y la cesión a EPSB de un número determinado de plazas de aparcamiento y la cubierta del aparcamiento urbanizada. Se trata pues de una construcción de iniciativa privada

An investigation of development appraisal methods employed by valuers and appraisers in small and medium sized practices in Brazil

Purpose – Whilst the real estate development appraisal practices of large national and international real estate companies are well understood, relatively little is known about how development appraisals are conducted by indigenous appraisers and valuers in developing countries. The purpose of this paper is to investigate how development appraisal is conducted in Brazil, compared to the UK, focusing primarily on the methods employed by small- and medium-sized real estate practices and their appraisers to appraise the viability of commercial real estate developments in the State of Sao Paulo. Design/methodology/approach – The study employs a two phase Delphi Method to capture and analyse empirical data from small- and medium-sized real estate appraisers in Brazil. Using the long established and relatively transparent UK Residual Method of development appraisal as a template against which to compare Brazilian appraisal methods, guidance and practice. To understand how indigenous development appraisers operate the Brazilian development appraisal methods, the research was conducted in Portuguese by a bi-lingual real estate expert who was familiar with both UK and Brazilian practice. Findings – The research establishes that appraisers working for small- and medium -sized real estate practices in Brazil rarely use the Residual Method. Instead, they employ a range of methods, the choice of which is heavily influenced by the availability of comparable market data, with Direct Comparison of market data and the Capitalisation of Income being the methods of choice when sufficient comparable evidence is available. Appraisers rarely employ the Residual Method as the principal development appraisal technique, using instead the Comparative Method and Discounted Cash Flow (DCF) analysis. Land prices are usually agreed or already known and developer’s profit is usually determined using DCF analysis and is highly sensitive to fluctuations in construction costs. Research limitations/implications – The research engaged with a small number of appraisers and valuers in small- and medium-sized practices in the State of Sao Paulo using a two-phase Delphi Method. The long established UK Residual Method of development appraisal was used as a template against which to compare practice in Sao Paulo State. There is potential therefore to replicate the research in other Brazilian States and transfer the methodology to other developing countries. Practical implications – In Brazil, when development land in urban areas is acquired on the basis of plot exchange, land is often sold at less than market value and the original landowner retains an equity stake in the development and shares in the development overage. The practice of “permuta física”, giving landowners the freehold of part of the development, or “permuta financeira”, whereby the landowner receives an enhanced land price, indexed against development value, is of potential relevance to the UK and other developed countries that need help in urban unlocking land markets

Using genomic annotations increases statistical power to detect eGenes.

MotivationExpression quantitative trait loci (eQTLs) are genetic variants that affect gene expression. In eQTL studies, one important task is to find eGenes or genes whose expressions are associated with at least one eQTL. The standard statistical method to determine whether a gene is an eGene requires association testing at all nearby variants and the permutation test to correct for multiple testing. The standard method however does not consider genomic annotation of the variants. In practice, variants near gene transcription start sites (TSSs) or certain histone modifications are likely to regulate gene expression. In this article, we introduce a novel eGene detection method that considers this empirical evidence and thereby increases the statistical power.ResultsWe applied our method to the liver Genotype-Tissue Expression (GTEx) data using distance from TSSs, DNase hypersensitivity sites, and six histone modifications as the genomic annotations for the variants. Each of these annotations helped us detected more candidate eGenes. Distance from TSS appears to be the most important annotation; specifically, using this annotation, our method discovered 50% more candidate eGenes than the standard permutation [email protected] or [email protected]

A geometric interpretation of the permutation pp-value and its application in eQTL studies

Permutation $p$-values have been widely used to assess the significance of linkage or association in genetic studies. However, the application in large-scale studies is hindered by a heavy computational burden. We propose a geometric interpretation of permutation $p$-values, and based on this geometric interpretation, we develop an efficient permutation $p$-value estimation method in the context of regression with binary predictors. An application to a study of gene expression quantitative trait loci (eQTL) shows that our method provides reliable estimates of permutation $p$-values while requiring less than 5% of the computational time compared with direct permutations. In fact, our method takes a constant time to estimate permutation $p$-values, no matter how small the $p$-value. Our method enables a study of the relationship between nominal $p$-values and permutation $p$-values in a wide range, and provides a geometric perspective on the effective number of independent tests.Comment: Published in at http://dx.doi.org/10.1214/09-AOAS298 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Characterization of combinatorially independent permutation separability criteria

The so-called permutation separability criteria are simple operational conditions that are necessary for separability of mixed states of multipartite systems: (1) permute the indices of the density matrix and (2) check if the trace norm of at least one of the resulting operators is greater than one. If it is greater than one then the state is necessarily entangled. A shortcoming of the permutation separability criteria is that many permutations give rise to dependent separability criteria. Therefore, we introduce a necessary condition for two permutations to yield independent criteria called combinatorical independence. This condition basically means that the map corresponding to one permutation cannot be obtained by concatenating the map corresponding to the second permutation with a norm-preserving map. We characterize completely combinatorically independent criteria, and determine simple permutations that represent all independent criteria. The representatives can be visualized by means of a simple graphical notation. They are composed of three basic operations: partial transpose, and two types of so-called reshufflings. In particular, for a four-partite system all criteria except one are composed of partial transpose and only one type of reshuffling; the exceptional one requires the second type of reshuffling. Furthermore, we show how to obtain efficiently for every permutation a simple representative. This method allows to check easily if two permutations are combinatorically equivalent or not.Comment: 9 pages, corrected proof of rule