Flute Studio Recital I

Flute Studio Recital I Tuesday, February 25, 2020 at 12noon Recital Hall James W. Black Music Center 1015 Grove Avenue Richmond, Va

Formaldehyde monitor for automobile exhausts

Device makes use of microwave spectral absorption in low-Q resonant Stark cell, and indications are that ultimate sensitivity of instrument is within 100 parts per billion of formaldehyde. Microwave source is very small and requires only six-volt dc bias for operation. Coarse tuning is accomplished mechanically and fine tuning by adjusting dc-bias voltage

Flute Studio Recital I

Flute Studio Recital IDaniel Stipe, pianoTuesday, October 1, 2019 at noonRecital HallJames W. Black Music Center 1015 Grove AvenueRichmond, Va

A PC-based bus monitor program for use with the transport systems research vehicle RS-232 communication interfaces

Experiment critical use of RS-232 data busses in the Transport Systems Research Vehicle (TSRV) operated by the Advanced Transport Operating Systems Program Office at the NASA Langley Research Center has recently increased. Each application utilizes a number of nonidentical computer and peripheral configurations and requires task specific software development. To aid these development tasks, an IBM PC-based RS-232 bus monitoring system was produced. It can simultaneously monitor two communication ports of a PC or clone, including the nonstandard bus expansion of the TSRV Grid laptop computers. Display occurs in a separate window for each port's input with binary display being selectable. A number of other features including binary log files, screen capture to files, and a full range of communication parameters are provided

If You're So Smart, Why Aren't You Rich? Belief Selection in Complete and Incomplete Markets

This paper provides an analysis of the asymptotic properties of consumption allocations in a stochastic general equilibrium model with heterogeneous consumers. In particular we investigate the market selection hypothesis, that markets favor traders with more accurate beliefs. We show that in any Pareto optimal allocation whether each consumer vanishes or survives is determined entirely by discount factors and beliefs. Since equilibrium allocations in economies with complete markets are Pareto optimal, our results characterize the limit behavior of these economies. We show that, all else equal, the market selects for consumers who use Bayesian learning with the truth in the support of their prior and selects among Bayesians according to the size of the their parameter space. Finally, we show that in economies with incomplete markets these conclusions may not hold. Payoff functions can matter for long run survival, and the market selection hypothesis fails.Market selection hypothesis, subjective beliefs, general equilibrium, incomplete markets, complete markets

Bidding Strategies in Internet Yankee Auctions: Theory and Evidence

In the past few years, we have witnessed a tremendous proliferation of transactions using the Internet as a virtual marketplace. U.S. News and World Report estimates the value of electronic commerce around $13 billion in 1998. In addition to transactions where prices are posted, sellers also use Internet auctions to sell goods such as clothing, collectibles, computers, and electronics. Current estimates place the value of auction transactions in the Internet at$30 million per week. A popular format for Internet auctions is the Yankee format. Here, a seller offers k identical units for sale, and bidders specify how many units they want and the per-unit price they want to pay. Bidding takes place progressively over a predetermined time period and the k highest bids at closing win the units at their specified prices. Ties are broken on the basis of quantities first and time of bidding second. Two features make these auctions different from standard auctions. First, unlike "live" auctions with fixed participation costs, entering each bid may be costly in a Yankee auction since bidding takes place over several hours (or days) and, in addition to connectivity cost, several minutes time must spend several registering the new price. Second, each time the bidder visits the auction site, she is uncertain about the competition since it is possible for more bidders to decide to enter before the closing. Here, we derive and characterize equilibrium strategies in simple Yankee auctions with stochastic demand. We show that costly bidding may induce bidders to bid high or jump bid in earlier rounds. These jump bids play a signaling role; they attempt to discourage later bidders from competing with established bidders. This way, under some conditions, both sender and receiver of the signal may be better off in equilibrium. The sender because deterring competition saves her the costs of additional bids, and the receiver because she avoids the costs of fruitless early competition. Here, we derive conditions on bidding costs and bidder types that result in a signaling equilibrium of this nature. We show that the characteristics of the equilibrium are closely related to the structure of demand uncertainty faced by the bidders since signal bidding has more strategic value when bidders anticipate further competition later in the auction. We use data from hundreds of Yankee Auctions to test some predictions of the jump-bidding model. In confirmation, we find (a) over 40% of the bidders in our sample enter jump bids, (b) any individual bidder is more likely to enter a jump bid as his first bid, (c) earlier bidders are more likely to enter jump bids than later bidders, (d) the relative size of a jump bid is increasing in the number of bidders relative to units being sold, and (e) the relative size of a jump bid is decreasing in the object's average value. We conclude with a discussion of the implications of costly bidding and jump-bidding strategies on Internet auction design.

Optimality and Natural Selection in Markets

Evolutionary arguments are often used to justify the fundamental behavioral postulates of competive equilibrium. Economists such as Milton Friedman have argued that natural selection favors profit maximizing firms over firms engaging in other behaviors. Consequently, producer efficiency, and therefore Pareto efficiency, are justified on evolutionary grounds. We examine these claims in an evolutionary general equilibrium model. If the economic environment were held constant, profitable firms would grow and unprofitable firms would shrink. In the general equilibrium model, prices change as factor demands and output supply evolves. Without capital markets, when firms can grow only through retained earnings, our model verifies Friedman's claim that natural selection favors profit maximization. But we show through examples that this does not imply that equilibrium allocations converge over time to efficient allocations. Consequently, Koopmans critique of Friedman is correct. When capital markets are added, and firms grow by attracting investment, Friedman's claim may fail. In either model the long-run outcomes of evolutionary market models are not well described by conventional General Equilibrium analysis with profit maximizing firms.evolution, natural selection, equilibrium, incomplete markets

Bidding Strategies in Internet Yankee Auctions

A bidding strategy commonly observed in Internet auctions, though not frequently in live auctions, is that of "jump-bidding," or entering a bid larger than necessary to be a current high bidder. In this paper, we argue that the cost associated with entering on-line bids and the uncertainty concerning bidding competition -- both of which distinguish Internet from live auctions -- can explain this phenomenon. We present a simple theoretical model that accounts for the preceding characteristics, and derive the conditions under which jump-bidding constitutes an equilibrium strategy in a format commonly used for on- line trading, the Yankee Auctionâ. We then present evidence recorded from hundreds of Internet auctions that is consistent with the basic predictions from our model. We find that jump-bidding is more likely earlier in an Internet auction, when jumping has a larger strategic value, and that the incentives to jump bid increase as bidder competition becomes stronger. Several of our results have implications for starting bid and minimum bid increment rules set by Internet auction houses. We also discuss possible means of reducing bidding costs, and evidence that Internet auctioneers are pursuing this goal.internet auctions, bidding costs, jump bidding

Transport systems research vehicle color display system operations manual

A recent upgrade of the Transport Systems Research Vehicle operated by the Advanced Transport Operating Systems Program Office at the NASA Langley Research Center has resulted in an all-glass panel in the research flight deck. Eight ARINC-D size CRT color displays make up the panel. A major goal of the display upgrade effort was ease of operation and maintenance of the hardware while maintaining versatility needed for flight research. Software is the key to this required versatility and will be the area demanding the most detailed technical design expertise. This document is is intended to serve as a single source of quick reference information needed for routine operation and system level maintenance. Detailed maintenance and modification of the display system will require specific design documentation and must be accomplished by individuals with specialized knowledge and experience

Report and Recommendations on Two Chilean Labor Force Surveys

For many years, Chile has benefited from two surveys of labor force developments for the “Greater Santiago Area.” One of these surveys dates back to the 1950s and is conducted by the University of Chile. The other is a national survey, conducted by the National Institute of Statistics (NIS), from which data are also available for the Santiago Metropolitan Area. Results, especially the rate of unemployment, do not always coincide, and this has been particularly the case for all years since 1998. This report studies this problem of non concurrence, identifies a number of areas for possible explanation, and makes recommendations for improvement of survey operations. Both surveys were found to follow quite well recommendations of the International Labor Organization regarding the measurement of employment and unemployment. Two significant areas in the report concern the questionnaires used for the surveys and data estimation techniques. Fourteen recommendations for improvements in the surveys are offered, with major attention focused on plans by the NIS to introduce an entirely new questionnaire in the near future. With respect to the University’s survey, the authors recommend changes in the basic questionnaire and survey weighting procedures. They also recommend improving data analysis (NIS), maintaining error profiles for data collection (both surveys), and using seasonal adjustment for statistical analysis (both).