Analyses (ISAE) hosts the preliminary results of the research projects carried out within ISAE. The diffusion of the papers is subject to the favourable opinion of an anonymous referee, whom we would like to thank. The opinions expressed are merely the Authors' own and in no way involve the ISAE responsability.The series is meant for experts and policy-makers with the aim of submitting proposals and raising suggestions and criticism.La serie "Documenti di Lavoro" dell'Istituto di Studi e Analisi Economica ospita i risultati preliminari di ricerche predisposte all'interno dell'ISAE: La diffusione delle ricerche è autorizzata previo il parere favorevole di un anonimo esperto della materia che qui si ringrazia. Le opinioni espresse nei "Documenti di Lavoro" riflettono esclusivamente il pensiero degli autori e non impegnano la responsabilità dell'Ente.La serie è destinata agli esperti e agli operatori di politica economica, al fine di formulare proposte e suscitare suggerimenti o critiche.Stampato presso la sede dell'Istituto ISAE -Piazza dell'Indipendenza, 4 -00185 RomaTel. +39-06444821; www.isae.it
ABSTRACTThe Joint harmonized Manufacturing survey for Italy, carried out by the Institute of Studies and Economic Analysis (ISAE, formerly ISCO), has a long history: it began on a quarterly basis in 1959, becoming monthly in 1962. The survey was then broadly modified in several occasions; in particular, in 1986 it was re-designed in order to provide data also at the regional level, adopting a new stratified random sample, the strata represented by the sector, region and size of the firm. In 1998, the sample was upgraded further, using an optimal allocation of the reporting units to the sample strata (Cochran, 1977). These changes satisfied the demand for more detailed and, at the same time, better harmonized data. However, at this stage, the processing of the results was still based on a very detailed industry grid based on the old NACE1970 classification, re-codified to obtain harmonized data for the Main Industrial Groups and total manufacturing. Size weights were used in the processing of the results, but there were still some differences in the elaboration of the data at the national and regional level, resulting in a not fully-fledged comparability between local and national data.For these reasons, in 2003 ISAE started a re-thinking of the manufacturing survey processing phase. The resulting re-engineering process recently implemented by ISAE is described in this paper. It has reached two main relevant goals: i. The underlying industrial structure for the aggregation of survey results is now based on the NACERev1.1 classification, at the 3-digit level, adapted to take into consideration the structure of Italian economy. ii. The weighting scheme is now based on a coherent system of size weights, based on a four-stage method in which, firstly, the balance B a,j for question a, firm j, is aggregated in each strata, using the j-firm employees as weights; in the following stages, the result for each strata is progress...