Critical Stock Research Articles

A Century of Psychoanalysis: Critical Retrospect and Prospect

At the end of the first century of psychoanalytic theory and therapy, this paper takes critical stock of its past performance as a theory of human nature, and as a therapy. An account of the distinction between the dynamic and cognitive species of unconscious is followed by a critique of Freudian and post-Freudian psychoanalysis, as well as by an unfavorable verdict on the reconstruction of psychoanalysis by the ?hermeneutic? philosophers. Concluding remarks assess the future prospects of psychoanalysis in the 21st century.

A Century of Psychoanalysis: Critical Retrospect and Prospect

At the end of the first century of psychoanalytic theory and therapy, this paper takes critical stock of its past performance as a theory of human nature, and as a therapy. An account of the distinction between the dynamic and cognitive species of unconscious is followed by a critique of Freudian and post-Freudian psychoanalysis, as well as by an unfavorable verdict on the reconstruction of psychoanalysis by the ?hermeneutic? philosophers. Concluding remarks assess the future prospects of psychoanalysis in the 21st century.

The American Put Option and Its Critical Stock Price

We derive an expression for the critical stock price for the American put. We start by expressing the put price as an integral involving first‐passage probabilities. This approach yields intuition for Merton's result for the perpetual put. We then consider the finite‐lived case. Using (1) the fact that the put value ceases to depend on time when the critical stock price is reached and (2) the result that an American put equals a European put plus an early‐exercise premium, we derive the critical stock price. We approximate the critical‐stock‐price function to compute accurate put prices.

Stock Rationing in an M/Ek/1 Make-to-Stock Queue

This paper considers the stock rationing problem of a single-item, make-to-stock production system with several demand classes and lost sales. When demand is Poisson and processing time has an Erlang distribution, we show that a single-state variable called work storage level can be employed to completely capture the information regarding inventory level and the status of current production. The optimal rationing policy can be characterized by a sequence of monotone critical work storage levels. For each demand class, there exists a work storage level at or below which it is optimal to start rejecting the demand of this class in anticipation of future arrival of higher-priority demands. The optimal production policy can also be characterized by a critical work storage level. Our numerical examples indicate that a critical stock level policy, which ignores information on the status of current production, performs very well.

Production planning problem in manufacturing systems with general failure and repair time distributions

We study the optimal flow control for a manufacturing system subject to random failures and repairs. In most previous work, it has been proved that, for constant demand rates and exponential failure and repair times distributions of machines, the hedging point policy is optimal. The aim of this study is to extend the hedging point policy to non-exponential failure and repair times distributions and random demand rates models. The performance measure is the cost related to the inventory and back order penalties. We find that the structure of the hedging point policy can be parametrized by a single factor representing the critical stock level or threshold. With the corresponding hedging point policy, simulation experiments are used to construct input-output data from which an estimation of the incurred cost function is obtained through a regression analysis. The best parameter value of the related hedging point policy is derived from a minimum search of the obtained cost function. The extended hedging point policy is validated and shown to be quite effective. We find that the hedging point policy is also applicable to a wide variety of complex problems (i.e. non-exponential failure and repair times distributions and random demand rates), where analytical solutions may not be easily obtained.

La imagen global y las posibilidades alternativas de la evolución del sistema-mundo, 1945-2025

The author takes critical stock of the main evolutionary tendencies shown by the history of the world-system between 1945 and 1990. On the basis of this global diagnosis, he explores possible prospective scenarios for the development of the world-economy during the period from 1990 to 2025

Optimal stopping, free boundary, and American option in a jump-diffusion model

This paper considers the American put option valuation in a jump-diffusion model and relates this optimal-stopping problem to a parabolic integro-differential free-boundary problem, with special attention to the behavior of the optimal-stopping boundary. We study the regularity of the American option value and obtain in particular a decomposition of the American put option price as the sum of its counterpart European price and the early exercise premium. Compared with the Black-Scholes (BS) [5] model, this premium has an additional term due to the presence of jumps. We prove the continuity of the free boundary and also give one estimate near maturity, generalizing a recent result of Barleset al. [3] for the BS model. Finally, we study the effect of the market price of jump risk and the intensity of jumps on the American put option price and its critical stock price.

Early Exercise Regions for Exotic Options

This article examines early exercise regions for American options on multiple assets and average-price options. One feature of the early exercise region for a standard American put option on a single asset is that, at any given time, there exists a critical stock price below which it is optimal to exercise the option. In other words, if it is optimal to exercise the option at a particular stock price at a particular time, it is also optimal to exercise in any state where the option has higher intrinsic value. We show that this property does not hold in general for non- standard options. In the case of options on multiple assets, there can be many states where it is better to hold an option whose intrinsic value is higher than in states where it is better to exercise. The number of such states depends on factors such as the nature of the option, the time remaining until maturity, the correlation between the assets, and their volatilities. In the case of average-price put options, an interesting feature is that the option is not exercised optimally at points with the highest intrinsic value at any time prior to maturity unless the interest rate is very high.

Species For Particular Uses

A theme of this publication is that each pasture species occupies a particular niche where it does better than others which might be used. In so doing each also tills a particular role in the juggling act between feed supply and animal requirements. We have stressed the need to identify the critical stock feed periods, and then to establish special purpose pastures to satisfy these requirements.

Dynamic optimization with a nonconvex technology: determination of critical stocks

Optimal management of resources could involve policies that lead to conservation or complete depletion of a resource. In the framework of a continuous time dynamic programming problem, a method for determining critical stocks, which partition these different optimal policies, is outlined. Such a critical stock has been described elsewhere in the literature as the minimum safe standard of conservation.