predicting the maintenance and management costs and replacement age of tractors in agricultural mechanized units, is important from several points. so, doing a timely agricultural operations, more accurate measure of the amount of income  including the cost of these items , determining the useful life of old tractors , replacement age, cost of the process changes and the possibility of examinin...

  The optimal harvesting policy is calculated as a function of the entering stock, the price state, the harvesting cost, and the rate of interest in the capital market. In order to determine the optimal harvest schedule, the growth function and stumpage price process are estimated for the Swedish mixed species forests. The stumpage price is assumed to follow a stochastic Markov process. A stoch...

In this paper, we construct a seasonally-adjusted price index for prepackaged software using detailed and comprehensive scanner data from the NPD Group. We document a large sales surge over the winter-holiday and claim that this seasonality is being driven by consumer heterogeneity. We introduce a novel approach for constructing the software component of the cost-of-living price index which exp...

the air in tehran is one of the most polluted airs in the entire world. because of the air pollution in the great tehran area, morbidity, mortality and symptoms emerge. this study has been conducted for the first time in iran. according to this study the total annual direct medical costs of morbidity estimated at us$ 3258255.48.our work also led to the estimation of an income elasticity of wtp ...

OBJECTIVES Measurement of the quality of care provided by managed care organizations (MCOs) has achieved national prominence, though there is controversy regarding its value. This article assesses the economic implications of a new Health Plan Employer Data and Information Set (HEDIS) measure for pneumococcal vaccination. METHODS A Markov decision model, with Monte Carlo simulations, was util...

gamma rays pose enough energy to remove electrons from atoms of absorbing material including human body and adversely affect human health. the external exposure of human beings to natural environmental gamma radiation normally exceeds that from all man-made sources combined. therefore, we monitored gamma dose rate in indoor environments and estimated corresponding annual effective dose in selec...

Predicting the maintenance and management costs and replacement age of tractors in agricultural mechanized units, is important from several points. So, doing a timely agricultural operations, more accurate measure of the amount of income  including the cost of these items , determining the useful life of old tractors , replacement age, cost of the process changes and the possibility of examinin...