Commentary: Are National Parks Still Relevant?

On the occasion of the National Parks centennial comes an irreverent question: Are the parks still relevant? Famously christened as America\u27s best idea by writer Wallace Stegner and reaffirmed in Ken Burns\u27 2009 PBS documentary, it seems brazen, if not blasphemous, to pose the question. [excerpt

Development of an analytical method to predict helicopter main rotor performance in icing conditions

Historically, certification of a helicopter for flight into known icing conditions was a problem. This is because of the current emphasis on flight testing for verification of system performance. Flight testing in icing conditions is difficult because, in addition to being dangerous and expensive, many times conditions which are sought after cannot be readily found in nature. The problem is compounded for helicopters because of their small range in comparison to many fixed wing aircraft. Thus, helicopters are forced to wait for conditions to occur in a certain region rather than seeking them out. These and other drawbacks to flight testing prompted extreme interest in developing validated alternatives to flight testing. One such alternative is theoretical prediction. It is desirable to have the ability to predict how a helicopter will perform when subjected to icing conditions. Herein, calculations are restricted to the main rotor, and are illustrated. The computational tool used to obtain performance is the lifting line analysis of B65. B65 incorporates experimental data into data banks in order to determine the section lift, drag, and moment characteristics of various airfoils at different Mach numbers and angles of attack. The local flow angle is calculated at user specified radial locations. This flow angle, along with the local Mach number is then cross referenced with the airfoil tables to obtain the local section characteristics. The local characteristics are then integrated together to obtain the entire rotor attributes. Once the clean performance is known, characterization of the type and shape of ice which accretes on the rotor blades is obtained using the analysis of LEWICE. The Interactive Boundary Layer (IBL) method then calculates the 2-D characteristics of the iced airfoil for input into the airfoil data bank of B65. Calculations are restricted to natural ice shedding and it is assumed that no de-icing takes place. Once the new lift, drag, and moment characteristics are known for the entire blade radius, this information is fed into B65, where the iced performance is then calculated

Ongoing development of a computer jobstream to predict helicopter main rotor performance in icing conditions

Work is currently underway at the NASA Lewis Research Center to develop an analytical method for predicting the performance degradation of a helicopter operating in icing conditions. A brief survey is performed of possibilities available to perform such a calculation along with the reasons for choosing the present approach. A complete description of the proposed jobstream is given as well as a discussion of the present state of the development

Family Control and the Rent-Seeking Society

The small number of very large family-controlled corporate groups in many countries combined with their long continuity of control and ability to act discretely give these organizations a comparative advantage in political rent-seeking. This advantage is a key part of a self-reinforcing system whereby oligarchic family corporate control, political rent seeking, and low general levels of trust combine to stymie growth.http://deepblue.lib.umich.edu/bitstream/2027.42/39971/3/wp585.pd

Responses of Private and Public Schools to Voucher Funding: The Czech and Hungarian Experience

A state monopoly in schooling followed the collapse of communism in Central Europe. The centrally planned system was abandoned. Systems comparable with educational voucher scheme, also known as school choice system, were introduced in the Czech Republic and Hungary in the early 1990s. The newly established system of school financing allocates public funds according to the number of students enrolled in a school. Accredited non-state schools, private and religious, are also eligible for public subsidies. The scope and the form of these reforms represent a unique opportunity to test conflicting hypotheses of proponents and opponents of the voucher scheme. In this empirical analysis, we test fundamental theoretical predictions of the voucher model. Specifically, we test: i) whether non-state schools are established at locations where the supply of educational opportunities provided by state schools is low or of low quality, ii) whether state and non-state schools in such a system respond to changes in demand for education, and iii) whether state schools respond to competition from non-state schools. We use detailed school level data on the whole population of schools and data on regional conditions. In our econometric model we estimate education value added, instead of relying on absolute quality of school graduates. We find that non-state schools emerge at locations with excess demand and lower quality state schools. We also find that greater competition from non-state schools creates incentives for state schools with the result that state schools slightly improve the quality of educational inputs used and significantly improve their output, quality of graduates. As concerns the technical schools, we find that non-state schools react to regional labor market conditions in terms of technical branch premium and unemployment rate. We do not find such reactions to market signals by state schools. We introduce this analysis with a review of non-state schools' development in the Czech Republic and Hungary during the 1990s.http://deepblue.lib.umich.edu/bitstream/2027.42/39744/3/wp360.pd

Survey-based Estimates of Biases in Consumer Price Indices During Transition: Evidence from Romania

Mismeasurement of inflation is likely to be more severe in a transition economy than in a more stable environment. Comparisons of self-reported changes in economic welfare with changes in incomes suggest that official Romanian inflation measures may be overstated by between 100 and 300 percent at a reported annual inflation rate of 40 per cent.

Lange and Hayek Revisited: Lessons from Czech Voucher Privatization

A fundamental question in economics since the 1930s has been whether an administrative price system could simulate the results of perfect competition even without a true market for the means of production. The theoretical possibility of such a system has been known since the introduction of market socialism by Oskar Lange. We have used the artificial bidding market involved in the Czech voucher privatization process to test whether a sequential process of trial-and-error can set administrative prices close to equilibrium. It would appear from this natural experiment that Robbins and Hayek were correct in doubting the real-world feasibility of market socialism.Bidding scheme, Oskar Lange’s model, Privatization, Price setting, Voucher scheme

Inflationary Bias in Mid to Late Transition Czech Republic

A series of studies confirm results presented Filer and Hanousek (2000) suggesting that mismeasurement of inflation during the transition is a serious problem, on the same relative order of magnitude (and greater in absolute magnitude) as in advanced market economies. Overall, inflation has been overstated by more than 4 percentage points a year during the 1990s in the Czech Republic. By far the largest portion of this bias is due to uncaptured quality changes. In effect, Czech consumers are living considerably better after the fall of communism, but this increase in living standards has manifested itself through better quality rather than greater quantities of goods consumed.Inflation Bias, Transition Economies, Output Fall