We suggest a non-parametric heteroscedasticity and autocorrelation consistent (HAC) estimator of the variance–covariance (VC) matrix for a vector of sample moments within a spatial context. We demonstrate consistency under a set of assumptions that should be satisfied by a wide class of spatial models. We allow for more than one measure of distance, each of which may be measured with error. Mon...

land cover mapping is important for many planning and management activities. today, satellite images and remote sensing techniques are extensively used in all sectors including agriculture and natural resources because they provide updated data and high analyzing abilities. in this study, in order to produce land cover map for the northern part of hamedan province , digital satellite data irsp6...

This paper analyzes optimal copyright levies in a representative consumer model and derives welfare implications for harmonization of levy rates. When the policymakers place enough weight on the interests of collecting societies, harmonization could lead to a reduction in social welfare. When countries are asymmetric, the country with a larger proportion of foreign consumption and more ine¢ cie...

This Working Paper should not be reported as representing the views of the IMF. The views expressed in this Working Paper are those of the author(s) and do not necessarily represent those of the IMF or IMF policy. Working Papers describe research in progress by the author(s) and are published to elicit comments and to further debate. A reduced-form model approach was used to estimate the trade ...

Penatti M.P.A., Silva A.S., Valadares G.F. & Leite D.S. 2005. Occurrence of F42 colonization factor in Escherichia coli strains isolated from piglets with diarrhea. Pesquisa Veterinária Brasileira 25(1):31-33. Depto Microbiologia e Imunologia, Instituto de Biologia, Unicamp, Campinas, SP 13081-970, Brazil. E-mail: [email protected] The objective of this study was to determine the presence of ...