Limit Theorems and Governing Equations for Levy Walks

The Levy Walk is the process with continuous sample paths which arises from consecutive linear motions of i.i.d. lengths with i.i.d. directions. Assuming speed 1 and motions in the domain of beta-stable attraction, we prove functional limit theorems and derive governing pseudo-differential equations for the law of the walker's position. Both Levy Walk and its limit process are continuous and ballistic in the case beta in (0,1). In the case beta in (1,2), the scaling limit of the process is beta-stable and hence discontinuous. This case exhibits an interesting situation in which scaling exponent 1/beta on the process level is seemingly unrelated to the scaling exponent 3-beta of the second moment. For beta = 2, the scaling limit is Brownian motion

FORVAL: Computer Software Package for Agricultural and Natural Resources Investment Analysis

The valuation of agricultural and natural resource investments presents challenging analysis problems that often require the use of computer software. Most of these computer packages are complex and costly. FORVAL is a free, user-friendly, menu-driven, agricultural and natural resource investment analysis package. It can accommodate any investment scenario and includes the standard financial criteria (net present value, rate of return, equal annual income, benefit/cost ratio, and land expectation value for forestry investments). FORVAL accommodates various cash flows like single sum, terminating annual and periodic series, and perpetual annual and periodic series. It also has options for payment and price projections

The effect of cave illumination on bats

Artificial light at night has large impacts on nocturnal wildlife such as bats, yet its effect varies with wavelength of light, context, and across species involved. Here, we studied in two experiments how wild bats of cave-roosting species (Rhinolophus mehelyi, R. euryale, Myotis capaccinii and Miniopterus schreibersii) respond to LED lights of different colours. In dual choice experiments, we measured the acoustic activity of bats in response to neutral-white, red or amber LED at a cave entrance and in a flight room – mimicking a cave interior. In the flight room, M. capaccinii and M. schreibersii preferred red to white light, but showed no preference for red over amber, or amber over white light. In the cave entrance experiment, all light colours reduced the activity of all emerging species, yet red LED had the least negative effect. Rhinolophus species reacted most strongly, matching their refusal to fly at all under any light treatment in the flight room. We conclude that the placement and light colour of LED light should be considered carefully in lighting concepts for caves both in the interior and at the entrance. In a cave interior, red LED light could be chosen – if needed at all – for careful temporary illumination of areas, yet areas important for bats should be avoided based on the precautionary principle. At cave entrances, the high sensitivity of most bat species, particularly of Rhinolophus spp., towards light sources almost irrespective of colour, calls for utmost caution when illuminating cave entrances

FORVAL: Computer Software Package for Agricultural and Natural Resources Investment Analysis

The valuation of agricultural and natural resource investments presents challenging analysis problems that often require the use of computer software. Most of these computer packages are complex and costly. FORVAL is a free, user-friendly, menu-driven, agricultural and natural resource investment analysis package. It can accommodate any investment scenario and includes the standard financial criteria (net present value, rate of return, equal annual income, benefit/cost ratio, and land expectation value for forestry investments). FORVAL accommodates various cash flows like single sum, terminating annual and periodic series, and perpetual annual and periodic series. It also has options for payment and price projections

What is your “effective” rate of reforestation cost?

If you are considering a reforestation investment, you should be concerned with its effective cost; ,that is, the cost of reforestation after considering interest arid timing of the tax savings and cost-share payments. Effective regeneration costs depend on your interest rate, marginal tax rate, and whether or not you receive assistance from a state or federal cost-share program

State cost-share programs for nonindustrial private forestry investments

Fourteen states provide cost-share assistance for approved forestry practices. Host programs are intended to increase forest productivity. Funding is typically from state appropriations and/or taxes on primary forest products. Cost-share rates range up to 80 percent, but most programs are at the 50 percent level. All programs require an approved forest management program. Eligible practices are generally reforestation, site preparation, and timber stand improvement

FORVAL for Windows: A computer program for forestry investment analysis

FORVAL for Windows is computer software designed to help evaluate timberland and forestry investments from a financial standpoint. It is free and user-friendlyso easy to use that a manual is not required (a Windows Help file is available as part of the program). While professional foresters will find it a valuable tool, it will be equally useful to private forest landowners

A note on after-tax analysis where capitalized costs are depreciated

Forest management often requires relatively long-term and capital intensive investments. Economic analysis of timber management alternatives can therefore be an extremely important aspect of decision-making. Investment analysis techniques are prominent in forest management texts and have also been the subject of many articles in the forestry literature. Any forestry investment analysis involves several important aspects. Topics included in reports by Gunter and Haney (1984) and Bullard et al. (1986), for example, include the treatment of inflation, income taxes, risk, and the choice of an appropriate discount rate. In this article, we focus on a very specific aspect of after-tax investment analysis-the appropriate, after-tax discount· rate where capitalized costs are depreciated. We discuss this aspect in particular because previous forestry texts, reports, and articles have not been explicit in stating that a tax adjusted discount rate is necessary in such cases

Bullish on Forestry Careers

During the next decade, baby boomer-aged foresters, those born from 1946 to 1964, will be retiring in large numbers. This retirement trend is true for all sectors of forestry employment, from state and federal agencies to private firms and industries. Forestry employers in both public and private sectors are clamoring for more graduates, as well as for more diverse graduates, from forestry degree programs. With looming retirements and industry growth, employers can project the number of positions opening, and they are aware that U.S. forestry schools are not producing sufficient graduates to fill the positions