1,721,077 research outputs found
Advertising decisions in a vertical distribution channel
No full textA manufacturer and a retailer are the members of a simple distribution channel for a
particular product in a segmented market. The advertising efforts of the two agents have
a joint effect on the goodwill of the different market segments and then on the demand.
The channel members aim at maximizing their profits, by choosing suitable advertising
media and efforts. We focus mainly on competition between manufacturer and retailer,
obtaining Nash equilibrium strategies, in the contexts of linear and concave demand. We
consider also the possibility of cooperation, obtaining the coordinated channel optimal
decisions
Further results on optimization of recognition time
No full textPrevious studies on optimization of computational time in pattern recognizers started from strong hypotheses of separability of the classes by a known recognizer and from consideration of naive algorithms which implement the recognizer. Here, we consider weaker separability hypotheses, which allow for doubtful cases, and slightly more sophisticated algorithms. The expressions of the mean computational length and of its total variation actually valid are presented with their relation to the old ones. We give evidence for the fact that the old criterion for deciding about the optimality of an algorithm, by simple ordering of the class-probabilities, is still applicable in this new setting
Computational length in pattern recognizers
No full textThe computational time of an absolute comparison recognizer is a random variable related to a measure of computational length. These variables depend on the choice of an algorithm which carries out the recognition. The expectation and the variance of the computational length are examined in detail with reference to the probability distribution of the classes to be discriminated. In particular, upper and lower bounds of the smallest mean computational length are found in easily evaluable forms
Inequalities concerning a random computational length of pattern recognizers
No full textThe computational length of an algorithm for pattern recognition by absolute comparison is a random variable, whose features depend on the probability distribution π∈Rk of the k classes to be discriminated. The Euclidean distance from the uniform probability distribution to any other distribution π is proportional to the greatest lower bound of the total variation of the mean computational length of algorithms used to recognize classes with distribution π. This result is reached by first finding a suitable basis of Rk which allows simple representations of probability distributions and of the functions under study. Furthermore, by using the same basis, the Schwartz inequality easily gives an upper bound of the total variation of the mean computational length
An adaptive multistage queueing system
No full textWith the ultimate aim of controlling the queue size, the conventional M/M/1 queueing model can be modified, in a number of ways, to allow for dependence of arrival and service processes. In this article one such modification is introduced and the resulting model is analyzed in detail. The service time of each customer is assumed to be the sum of a random number of independent exponential variables, each of which represents one stage of service. The number of stages has a presumed distribution, with the added adaptive mechanism of curtailing the nth service time upon the completion of the stage during which the first customer, whose arrival time is after the commencement of the nth service, joins the system. Initially, an expression is derived for the moment-generating function of the effective service times. By differentiating this expression, the effective traffic intensity is given which, as expected, depends on the mean number of stages. Then, by using the transition probabilities of an imbedded Markov chain, the stationary queue size distribution at departure times is obtained. An approximate expression is also given for the mean waiting time. The paper is concluded with examples of specific distributions (geometric and Poisson) for the number of stages, along with the degenerate case---namely, one stage with probability one which corresponds to M/M/1
Optimization of computational time in pattern recognizers
No full textA sequential organization of the computations arising from pattern recognizers by absolute comparison is suggested in order to reduce the mean computational time involved. This optimization problem is solved by means of a supervising system which exploits the information obtained from the pattern-vector through a preclassifier: this information has the form of a conditional probability distribution of the classes to which the pattern-vector may belong. The results are extended to pattern recognizers by relative comparison
Coupled recognizers
No full textWe tackle the problem of minimizing the mean computational length of pattern recognizers by absolute comparison, i. e. the average number of discriminant functions to be computed in such recognizers. To this end we consider the possibility of exploiting a less precise recognizer as a supervising system for the main recognizer. Once the optimal solution is analyzed, some conditions about the behaviour of the auxiliary recognizer are considered in order to simplify the algorithm involved and to find simpler suboptimal algorithms
Advertising decisions for a segmented market
No full textWe consider the problem of choosing the levels of a set of advertising media in order to maximize the firm profit when the market is heterogeneous. Advertising efforts affect the demand of the different segments variably and we assume that the advertising effects on demand over time are mediated by a vector goodwill variable. A first general advertising decision problem is stated and solved in the non-linear programming framework. A preference index is then obtained for the medium selection problem when each segment demand function is linear in goodwill and each medium advertising cost function is quadratic in its level. Finally the theoretical case of disjoint advertising media is discussed
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