Heterogeneous products and tests for an appropriate aggregation level considering different qualities: evidence from fresh hake at Barcelona’s wholesale market

[cat] Aquest estudi destaca la importància de considerar un nivell d’agregació adequat en els anàlisis de demanda, ja que treballar utilitzant un nivell d’agregació inadequat pot donar lloc a estimacions esbiaixades. Aquest fet es mostra a través de l’anàlisi de diferents productes de lluç fresc comercialitzats a Mercabarna, el mercat majorista de Barcelona. La literatura sobre la demanda de peix tracta al lluç com un únic producte i espècie. No obstant això, en el mercat espanyol, es comercialitzen molts peixos com a lluç, els quals mostren comportaments molt diferents (des de béns inferiors fins a béns de luxe). Els resultats obtinguts, en concordança amb les observacions empíriques, demostren que l’anàlisi s’ha de realitzar amb un major grau de detall que a nivell d’espècie. Això qüestiona els resultats d’anteriors estudis de demanda i la majoria de les bases de dades, on l’observació del nivell d’agregació adequat dels productes no es té en compte.[eng] This paper stresses the importance of considering an appropriate aggregation level for databases and demand analyses, as an inappropriate level may lead to biased estimates. This is illustrated by an analysis of different fresh hake products from Mercabarna, Barcelona’s wholesale market. The literature on seafood demand regards hake as a single product species. Nevertheless, in the Spanish market, many types of fish, ranging from inferior to luxury goods, are marketed as hake. Our results were in accordance with empirical observations, and suggest the need for analysis at a greater depth than the species level. Thus, this questions the results of previous demand studies and most databases, which have not taken the appropriate product aggregation level into account

Global Competition, Institutions, And The Diffusion Of Organizational Practices: The International Spread Of Iso 9000 Quality Certificates

We use panel data on ISO 9000 quality certification in 85 countries between 1993 and 1998 to better understand, the cross-national diffusion of an organizational practice. Following neoinstitutional theory, we focus on the coercive, normative, and mimetic effects that result from the exposure of firms in a given country to a powerful source of critical resources, a common pool of relevant technical knowledge, and the experiences of firms located in other countries. We use social network theory to develop a systematic conceptual understanding of how firms located in different countries influence each other's rates of adoption as a result of cohesive and equivalent network relationships. Regression results provide support for our predictions that states and foreign multinationals are the key actors responsible for coercive isomorphism, cohesive trade relationships between countries generate coercive and normative effects, and role-equivalent trade relationships result in learning-based and competitive imitation.Business Administratio

Efficient Systematic Encoding of Non-binary VT Codes

Varshamov-Tenengolts (VT) codes are a class of codes which can correct a single deletion or insertion with a linear-time decoder. This paper addresses the problem of efficient encoding of non-binary VT codes, defined over an alphabet of size $q >2$. We propose a simple linear-time encoding method to systematically map binary message sequences onto VT codewords. The method provides a new lower bound on the size of $q$-ary VT codes of length $n$.Comment: This paper will appear in the proceedings of ISIT 201

My first year research experience: RAPS.

Presented at: 2016 Shared Knowledge Conference, University of New Mexico; April 11, 2016; Albuquerque, NM.https://digitalrepository.unm.edu/prc-posters-presentations/1028/thumbnail.jp