A 10% suckling rat brain rabies vaccine free from encephalitogenic activity was prepared and inactivated with 1:8,000 beta-propiolactone (BPL), or ultraviolet light, or a combination of ultraviolet light and BPL, or 1% phenol. Potency was excellent in all samples, with the exception of the phenolized product which was marginal. A purified suckling rat brain (SRB) vaccine prepared by zonal centr...

We present a continuous-time generalization of the seminal R&D model of d’Aspremont and Jacquemin (The American Economic Review 78(5): 1133–1137, 1988) to examine the trade-off between the benefits of allowing firms to cooperate in R&D and the corresponding increased potential for product market collusion. We consider all trajectories that are candidates for an optimal solution as well as initi...

Previous theoretical researches show that learning from good performers yields intense competition and results in the low profitability of firms. These researchers do not take into account differentiation strategies being referred as a useful strategic tool to mitigate competition. We introduce an evolutionary (learning) game into a duopoly model with product differentiation on the Hotelling li...

The welfare gain to consumers from the introduction of personal computers is estimated here. A simple model of consumer demand is formulated that uses a slightly modi…ed version of standard preferences. The modi…cation permits marginal utility, and hence total utility, to be …nite when the consumption of computers is zero. This implies that the good won’t be consumed at a high enough price. It ...

The monopolist’s incentives towards product and process innovations are evaluated against the social optimum. The main ...ndings are that (i) the incentive to invest in cost-reducing R&D is inversely related to the number of varieties being supplied at equilibrium, under both regimes; (ii) distortions obtain under monopoly, w.r.t. both the number of varieties and the technology. With substitute...

T -product extensions (where T is a continuous t-norm) of a system of low-dimensional possibility distributions form an important class of solutions of the so-called possibilistic marginal problem. Nevertheless, they can differ from each other, e.g., from the viewpoint of inference. Therefore the need for their interpretation is obvious. To find it, we identify any possibility distribution with...

The welfare gain to consumers from the introduction of personal computers is estimated. A simple model of consumer demand is formulated that uses a slightly modi…ed version of standard preferences. The modi…cation permits marginal utility, and hence total utility, to be …nite when the consumption of computers is zero. This implies that the good won’t be consumed at a high enough price. It also ...

We incorporate marginal cost savings from bundling, fixed costs of product offerings, and variation in customer preferences into a model of bundling and tying. To focus on cost effects, we assume perfectly contestable markets and analyze sustainable product offerings. Pure bundling can arise either because few people demand only one component or because, with high fixed costs, a single product ...

We investigate the timing of adoption of product and process innovation by using a differential game in which firms may invest in both activities. We consider horizontal product innovation that reduces product substitutability, and process innovation that reduces marginal cost. First, we demonstrate that the incentive for cost-reducing investment is relatively higher than the incentive to incre...

where u ∼ N(0, G) and 2 ∼ N(0, R) with u and 2 independent. This model can be interpreted as Y |β, u ∼ N(Xβ+Zu,R), u ∼ N(0, G), yielding (on integrating out u) the marginal model Y |β ∼ N(Xβ,ZGZ + R). Let V = ZGZ + R. Then the maximum penalized likelihood estimates of β and u given G and R are given by θ̂ = [ β̂ û ] = (CTR−1C + B)−1CTR−1y (A.2) where C = [X Z] and B is the block diagonal matrix w...