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This study aims to present an empirical model designed to forecast bank credit ratings using only quantitative and publicly available information from their financial statements. For this reason, the authors use the long-term ratings provided by Fitch in 2012. The sample consists of 92 US banks and publicly available information in annual frequency from their financial statements from 2008 to 2011.

First, in the effort to select the most informative regressors from a long list of financial variables and ratios, the authors use stepwise least squares and select several alternative sets of variables. Then, these sets of variables are used in an ordered probit regression setting to forecast the long-term credit ratings.

Under this scheme, the forecasting accuracy of the best model reaches 83.70 percent when nine explanatory variables are used.

The results indicate that bank credit ratings largely rely on historical data making them respond sluggishly and after any financial problems are already known to the public.

The purpose of this paper is to investigate the surface corrosion products of copper alloys by non‐destructive techniques (NDT) and correlate them with their bulk composition.

Specimens of copper alloys, whose compositions were close to those of ancient copper‐based artefacts, were left to be corroded in simulated soil solution containing ammoniacal buffering solution of pH =10 in 1:1 ratio, in order to accelerate the corrosion rate. The elemental compositions of the surface corrosion products were determined versus time using X‐Ray Fluorescence Spectroscopy, and the surface morphology by Scanning Electron Microscopy with Energy Dispersive X‐Ray Micro‐detector methods, and the results were compared to the bulk composition, as measured by Atomic Absorption Spectroscopy and Inductively Coupled Plasma Atomic Emission Spectroscopy.

During the corrosion evolution of the copper alloys in the corrosive solution, transitional phenomena were observed such as an initial decrease of the copper concentration with a simultaneous increase of the concentrations of the secondary alloying metals (Sn, Zn and Pb). After 30‐60 immersion days, the alloy concentrations were stabilised.

The results of this research could contribute to the non‐destructive characterisation of copper‐based ancient artefacts (from which the taking of samples is not allowed).