Investigating international new product diffusion speed: A semiparametric approach

Global marketing managers are interested in understanding the speed of the new product diffusion process and how the speed has changed in our ever more technologically advanced and global marketplace. Understanding the process allows firms to forecast the expected rate of return on their new products and develop effective marketing strategies. The most recent major study on this topic [Marketing Science 21 (2002) 97--114] investigated new product diffusions in the United States. We expand upon that study in three important ways. (1) Van den Bulte notes that a similar study is needed in the international context, especially in developing countries. Our study covers four new product diffusions across 31 developed and developing nations from 1980--2004. Our sample accounts for about 80% of the global economic output and 60% of the global population, allowing us to examine more general phenomena. (2) His model contains the implicit assumption that the diffusion speed parameter is constant throughout the diffusion life cycle of a product. Recognizing the likely effects on the speed parameter of recent changes in the marketplace, we model the parameter as a semiparametric function, allowing it the flexibility to change over time. (3) We perform a variable selection to determine that the number of internet users and the consumer price index are strongly associated with the speed of diffusion.Comment: Published in at http://dx.doi.org/10.1214/11-AOAS519 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Bright solitons in asymmetrically trapped Bose-Einstein condensate

We study the dynamics of bright solitons in a Bose-Einstein condensate (BEC) confined in a highly asymmetric trap. While working within the f ramework of a variational approach we carry out the stability analysis o f BEC solitons against collapse. When the number of atoms in the soliton exceeds a critical number $N_c$, it undergoes the so called primary col lapse. We find an analytical expression for $N_c$ in terms of appropriat e experimental quantities that are used to produce and confine the conde nsate. We further demonstrate that, in the geometry of the problem consi dered, the width of the soliton varies inversely as the number of consti tuent atoms.Comment: 5 pages, 1 figure

The ‘Peter Pan Syndrome’ in Emerging Markets: The Productivity-Transparency Tradeoff in IT Adoption

Firms make investments in technology to increase productivity. But in emerging markets, where a culture of informality is widespread, information technology (IT) investments leading to greater transparency can impose a cost through higher taxes and need for regulatory compliance. This tendency of firms to avoid productivity-enhancing technologies and remain small to avoid transparency has been dubbed the “Peter Pan Syndrome.” We examine whether firms make the tradeoff between productivity and transparency by examining IT adoption in the Indian retail sector. We find that computer technology adoption is lower when firms have motivations to avoid transparency. Specifically, technology adoption is lower when there is greater corruption, but higher when there is better enforcement and auditing. So firms have a higher productivity gain threshold to adopt computers in corrupt business environments with patchy and variable enforcement of the tax laws. Not accounting for this motivation to hide from the formal sector underestimates productivity gains from computer adoption. Thus in addition to their direct effects on the economy, enforcement, auditing and corruption can have indirect effects through their negative impact on adoption of productivity enhancing technologies that also increase operational transparency

Electron-nucleus scalar-pseudoscalar interaction in PbF: Z-vector study in the relativistic coupled-cluster framework

The scalar-pseudoscalar interaction constant of PbF in its ground state electronic configuration is calculated using the Z-vector method in the relativistic coupled-cluster framework. The precise calculated value is very important to set upper bound limit on P,T-odd scalar-pseudoscalar interaction constant, k_s, from the experimentally observed P,T-odd frequency shift. Further, the ratio of the effective electric field to the scalar-pseudoscalar interaction constant is also calculated which is required to get an independent upper bound limit of electric dipole moment of electron, d_e, and k_s and how these (d_e and k_s) are interrelated is also presented here.Comment: 6 pages, 1 figure

Research Notes : India : Environmental impact on different characteristics of soybean

The leguminous protein and oil rich crop soybean requires specific environrnent for its successful growth and yield. The variation in yield levels and restricted adaptation are mostly due to photoperiodic requirements (Weber and Moorthy, 1952) and probably due to thermal sensitivity (Leng, 1968). The nature and magnitude of variability present in an individual or a population is due to both genetic and nongenetic causes

Home Internet Access and Usage in the USA: Trends in the Socio-Economic Digital Divide

Past research has found evidence of the existence of a significant digital divide among various socio-economic segments in terms of Internet access and usage. In this research, we use two annual (2002 and 2008) cohorts of demographically representative national random samples to investigate the relative levels of digital divide along the typical socio-economic fault lines. We find from our statistical analyses that not only does a deep digital divide still persist along key dimensions (like education) of the socio-economic fault lines, it has in fact widened along several key dimensions (like income and urban-rural divide)