Random Latin squares and Sudoku designs generation

Uniform random generation of Latin squares is a classical problem. In this paper we prove that both Latin squares and Sudoku designs are maximum cliques of properly defined graphs. We have developed a simple algorithm for uniform random sampling of Latin squares and Sudoku designs. It makes use of recent tools for graph analysis. The corresponding SAS code is annexed

Generation of Fractional Factorial Designs

The joint use of counting functions, Hilbert basis and Markov basis allows to define a procedure to generate all the fractions that satisfy a given set of constraints in terms of orthogonality. The general case of mixed level designs, without restrictions on the number of levels of each factor (like primes or power of primes) is studied. This new methodology has been experimented on some significant classes of fractional factorial designs, including mixed level orthogonal arrays.Comment: 27 page

Incentives and uncertainty: an empirical analysis of the impact of demand on innovation

demand, product innovation, process innovation

Product entry in a fast growing industry: the LAN switch market

We provide empirical evidence on market positioning by firms, in terms of market niche, distance from technological frontier and dispersion. We focus on the switch industry, a sub-market of the Local Area Network industry, in the nineties. Market positioning is a function of the type of firms (incumbents versus entrants), market size and contestability and firm competencies. We find that incumbents specialise in high-end segments and disperse their product in a larger spectrum of the market. Instead, entrants focus on specific market niches. Market size, market contestability and firm competencies are also important determinants of product location.switch industry, markets, competition, firm capabilities, product entry