Hedonic Price Indices for the Paris Housing Market

In this paper, we calculate a transaction-based price index for apartments in Paris (France). The heterogeneous character of real estate is taken into account using an hedonic model. The functional form is specified using a general Box-Cox function. The data basis covers 84 686 transactions of the housing market in 1990:01-1999:12, which is one of the largest samples ever used in comparable studies. Low correlations of the price index with stock and bond indices (first differences) indicate diversification benefits from the inclusion of real estate in a mixed asset portfolio

Construction of a transaction based real estate index for the Paris housing market

Der vorliegende Beitrag zeigt auf, wie hedonische Preisindizes für Immobilien auf der Basis von Transaktionen berechnet werden können. Der Heterogenität der Immobilien wird dabei durch ein ökonometrisches Modell Rechnung getragen, wobei in dieser Arbeit das Problem der Wahl einer geeigneten Funktionsform durch eine Transformation nach dem Ansatz von Box/Cox (1964) explizit berücksichtigt wird. Die Datenbasis deckt etwa 65% der Transaktionen des Wohnungsmarktes im Zeitraum 1990-1999 ab. Die Korrektur aufgrund unvollständiger Angaben führt zu einem Datensatz von 84 686 Transaktionen. Dieser Datensatz ist ein Vielfaches dessen, was bisher vergleichbaren Studien zugrunde lag und stellt damit eine international einmalige Datengrundlage dar.In this Paper, we calculate a transaction based price index for apartments in Paris (France). The heterogeneous character of real estate is taken into account by using an econometric model. The functional form is specified by using a general Box/Cox-function. The data base Covers about 65% of the housing market in 1990-1999. Correction for incomplete data leads to a sample of 84 686 transactions. This sample is by far the largest ever used in comparable studies, and is therefore internationally an unique data coverage for housing markets

Konstruktion transaktionsbasierter Immobilienindizes : theoretische Grundlagen und empirische Umsetzung für den Wohnungsmarkt in Paris

Der vorliegende Beitrag zeigt auf, wie hedonische Preisindizes für Immobilien auf der Basis von Transaktionen berechnet werden können. Der Heterogenität der Immobilien wird dabei durch ein ökonometrisches Modell Rechnung getragen, wobei dieser Arbeit das Problem der Wahl einer geeigneten Funktionsform durch eine Transformation nach dem Ansatz von Box/Cox (1964) explizit berücksichtigt wird. Die Datenbasis deckt etwa 65% der Transaktionen des Wohnungsmarktes im Zeitraum 1990 - 1999 ab. Die Korrektur aufgrund unvollständiger Angaben führt zu einem Datensatz von 84686 Transaktionen. Dieser Datensatz ist ein Vielfaches dessen, was bisher vergleichbaren Studien zugrunde lag und stellt damit eine international einmalige Datengrundlage dar

MORPHOLOGICAL AND PHYSIOLOGICAL RESPONSES TO IRRADIANCE IN THE CAM EPIPHYTE TILLANDSIA USNEOIDES L. (BROMELIACEAE)

This is the publisher's version, also available electronically from: http://www.jstor.org/stable/10.2307/2474626Spanish moss (Tillandsia usneoides L.) was collected in situ in South Carolina from sunny and shady locations and grown in a greenhouse under high and low irradiance. Morphological characteristics, including leaf size, internode length, trichome size and density, and stomatal size and density, were similar among plants at the different irradiance levels. Chlorophyll (Chi) a/b ratios did not change with irradiance, but total Chi concentrations were higher in plants exposed to lower irradiances. In spite of these changes in pigment composition, similar levels of nocturnal acidification were found in field, but not greenhouse, plants at all irradiance levels. Thus, Spanish moss can respond physiologically, but not morphologically, to changes in environmental irradiance levels. This ability should prove beneficial to an epiphyte growing in microsites of widely varying irradiance

Heats of formation of perchloric acid, HClO4_4, and perchloric anhydride, Cl2_2O7_7. Probing the limits of W1 and W2 theory

The heats of formation of HClO$_4$ and Cl$_2$O$_7$ have been determined to chemical accuracy for the first time by means of W1 and W2 theory. These molecules exhibit particularly severe degrees of inner polarization, and as such obtaining a basis-set limit SCF component to the total atomization energy becomes a challenge. (Adding high-exponent $d$ functions to a standard $spd$ basis set has an effect on the order of 100 kcal/mol for Cl$_2$O$_7$.) Wilson's aug-cc-pV(n+d)Z basis sets represent a dramatic improvement over the standard aug-cc-pVnZ basis sets, while the aug-cc-pVnZ+2d1f sequence converges still more rapidly. Jensen's polarization consistent basis sets still require additional high-exponent $d$ functions: for smooth convergence we suggest the \{aug-pc1+3d,aug-pc2+2d,aug-pc3+d,aug-pc4\} sequence. The role of the tight $d$ functions is shown to be an improved description of the Cl (3d) Rydberg orbital, enhancing its ability to receive back-bonding from the oxygen lone pairs. In problematic cases like this (or indeed in general), a single SCF/aug-cc-pV6Z+2d1f calculation may be preferable over empirically motivated extrapolations. Our best estimate heats of formation are $\Delta H^\circ_{f,298}[$HClO$_4$(g)$]=-0.6\pm$1 kcal/mol and $\Delta H^\circ_{f,298}[$Cl$_2$O$_7$(g)$]=65.9\pm$2 kcal/mol, the largest source of uncertainty being our inability to account for post-CCSD(T) correlation effects. While G2 and G3 theory have fairly large errors, G3X theory reproduces both values to within 2 kcal/mol.Comment: J. Mol. Struct. (THEOCHEM), in press (WATOC'05 special issue

Investigating absolute stereochemical configuration with coulomb explosion imaging

It is a particularly challenging task in stereochemistry to determine the absolute configuration of chiral molecules, i.e. to assign to a given sample the microscopic enantiomeric structure. In recent years, Coulomb Explosion Imaging (CEI) has been shown to yield directly the absolute configuration of small molecules in the gas phase. This contribution describes the experimental basics of this approach, highlights the most significant results and discusses limitations. A short discussion on extending Coulomb Explosion Imaging beyond analytic aspects to fundamental questions of molecular chirality concludes this review