Expectations,network effects and timing of technology adoption: some empirical evidence from a sample of SMEs in Italy

We provide evidence on the influence of expectations and network effects on the timing of technological adoption. By considering a sample of SMEs operating in Italy, we focus on the determinants of their decision to adopt Fast Ethernet, a communication standard for Local Area Networks (LANs). We find that both expectations and network effects significantly affect the timing of adoption. In particular, price expectations generally tend to delay adoption and (indirect) network effects in the form of backward compatibility as well as informational spillovers tend to foster adoption. Firm size also matters.

Incremental costs associated with myocardial infarction and stroke in patients with type 2 diabetes mellitus: an overview for economic modeling

Objective:

To identify cost estimates related to myocardial infarction (MI) or stroke in patients with type 2 diabetes mellitus (T2DM) for use in economic models.

Methods:

A systematic literature review was conducted. Electronic databases and conference abstracts were screened against inclusion criteria, which included studies performed in patients who had T2DM before experiencing an MI or stroke. Primary cost studies and economic models were included. Costs were converted to 2012 pounds sterling.

Results:

Fifty-four studies were identified: 13 primary cost studies and 41 economic evaluations using secondary sources for complication costs. Primary studies provided costs from 10 countries. Estimates for a fatal event ranged from £2482–£5222 for MI and from £4900–£6694 for stroke. Costs for the year a non-fatal event occurred ranged from £5071–£29,249 for MI and from £5171–£38,732 for stroke. Annual follow-up costs ranged from £945–£1616 for an MI and from £4704–£12,926 for a stroke. Economic evaluations from 12 countries were identified, and costs of complications showed similar variability to the primary studies.

Discussion:

The costs identified within primary studies varied between and within countries. Many studies used costs estimated in studies not specific to patients with T2DM. Data gaps included a detailed breakdown of resource use, which affected the ability to compare data across countries.

Conclusions:

In the development of economic models for patients with T2DM, the use of accurate estimates of costs associated with MI and stroke is important. When country-specific costs are not available, clear justification for the choice of estimates should be provided.     

Modelling the supply of ecosystem services from agriculture: a minimum‐data approach*

We argue that to support agriculture–environmental policy decision making, stakeholders need ‘quantitative back‐of‐the‐envelope’ analysis that is timely and sufficiently accurate to make informed decisions. We apply this concept to the analysis of the supply of ecosystem services from agriculture. We present a spatially explicit production model and show how it can be used to derive the supply of ecosystem services in a region. This model shows that the supply of ecosystem services can be derived from the spatial distribution of opportunity cost of providing those services. We then show how this conceptual model can be used to develop a minimum‐data (MD) approach to the analysis of the supply of ecosystem services from agriculture that can be implemented with the kinds of secondary data that are available in most parts of the world. We apply the MD approach to simulate the supply of carbon that could be sequestered in agricultural soils in the dryland grain‐producing region of Montana. We find that the supply curve derived from the MD approach can approximate the supply curve obtained from a more elaborate model based on site‐specific data, and can do so with sufficient accuracy for policy analysis.     

Beta-product dependent Pitman–Yor processes for Bayesian inference

Multiple time series data may exhibit clustering over time and the clustering effect may change across different series. This paper is motivated by the Bayesian non-parametric modelling of the dependence between clustering effects in multiple time series analysis. We follow a Dirichlet process mixture approach and define a new class of multivariate dependent Pitman–Yor processes (DPY). The proposed DPY are represented in terms of vectors of stick-breaking processes which determine dependent clustering structures in the time series. We follow a hierarchical specification of the DPY base measure to account for various degrees of information pooling across the series. We discuss some theoretical properties of the DPY and use them to define Bayesian non-parametric repeated measurement and vector autoregressive models. We provide efficient Monte Carlo Markov Chain algorithms for posterior computation of the proposed models and illustrate the effectiveness of the method with a simulation study and an application to the United States and the European Union business cycle.     

Convergence and divergence in regional agricultural productivity growth: evidence from Italian regions, 1951–2002

This article analyzes long‐term agricultural Total Factor Productivity (TFP) growth at regional level by testing its time‐series properties and identifying factors associated with divergence as opposed to convergence. The empirical application concerns Italian regions over the 1951–2002 time period. TFP growth decomposition ultimately attributes the observed productivity growth performance to these contrasting (convergence vs. divergence) forces. We find that technological spillovers are the key convergence force regardless of how the spillover effects are computed. At the same time, forces favoring convergence are almost offset by divergence forces (mainly scale or learning effects). This decomposition may explain the persistence of TFP growth rate differences in Italian agriculture, and could be applicable elsewhere.     

Golden cages for showy birds: Optimal switching costs in labor contracts

Under what circumstances do workers sign contracts with high quitting penalties? Our answer points to market transparency. When the worker's performance is privately observed by the incumbent firm, alternative employers face an adverse selection problem. As a result, efficient separations can only take place through involuntary layoffs and there is no role for quitting fees. In contrast, when performance is public, quitting fees are useful devices to appropriate the surplus from workers’ reallocation. Separations are amicable and take the form of quitting after downwardly renegotiating the fees. Qualitative features of contracts are independent of the distribution of ex-post bargaining power. The impact of switching costs on total welfare and its distribution depends on the degree of market transparency and the ex-ante distribution of market power.     

Building the Knowledge Stock: Lags,Depreciation, and Uncertainty in R&D Investment and Link with Productivity Growth

The search for an appropriate methodology to investigate the relation between R&D investment, knowledge stock and productivity growth is the main purpose of the paper. In analogy with physical assets, we present a model of knowledge capital formation which allows the calculation of the relevant user cost, as well. The proposed model accumulates R&D investment based on a stochastic gestation lag and a geometric depreciation of the stock. The basic parameters underlying the lag structure differ according to the types of research expenditure. The approach is applied to public R&D investment in Italian agriculture; the results provide interesting information about the economic structure of public research effort in Italian agriculture and plausible estimates of its internal rate of return.     

Decentralized trade, random utility and the evolution of social welfare

We study decentralized trade processes in general exchange economies and house allocation problems with and without money. The processes are affected by persistent random shocks stemming from agents’ maximization of random utility. By imposing structure on the utility noise term—logit distribution—one is able to calculate exactly the stationary distribution of the perturbed Markov process for any level of noise. We show that the stationary distribution places the largest probability on the maximizers of weighted sums of the agents’ (intrinsic) utilities, and this probability tends to 1 as noise vanishes.     

Personal Income Distribution and Market Structure

Income distribution affects market demand and its elasticity, and, as a consequence, the optimal behaviour of firms and market equilibrium. This paper focuses on the effects of income polarization, and presents a model where – for any unimodal density function describing income distribution of the consumers – income polarization leads to market concentration, i.e., to a smaller number of firms able to survive in the long run, provided that the firms' fixed costs are sufficiently low.