Perceived Water Prices and Estimated Water Demand in the Residential Sector of Windhoek, Namibia. An Analysis of the Different Water Market Segments

We develop a demand model for the water market of Windhoek, Namibia, and segment the market by income. The model uses the perceived price concept developed by Shin (1985). Results confirm the Shin hypotheses that consumers dont know actual prices, but respond to perceived prices. The average price and covariates have the expected signs. However, marginal price (MP) coefficient is positive. Shins perception parameter (k) is negative in two of three income segments. In the Shin model, this implies that consumers respond to MP (through perceived prices). Ambiguities about prices warrant further investigation.Resource /Energy Economics and Policy,

Speculative attacks : unique sunspot equilibrium and transparency

Models with multiple equilibria are a popular way to explain currency attacks. Morris and Shin (1998) have shown that, in the context of those models, unique equilibria may prevail once noisy private information is introduced. In this paper, we generalize the results of Morris and Shin to a broader class of probability distributions and show - using the technique of iterated elimination of dominated strategies - that uniqueness will hold, even if we allow for sunspots and individual uncertainty about strategic behavior of other agents. We provide a clear exposition of the logic of this model and we analyse the impact of transparency on the probability of a speculative attack. For the case of uniform distribution of noisy signals, we show that increased transparency of government policy reduces the likelihood of attacks. JEL Classification F 31, D 82Modelle mit multiplen Gleichgewichten sind ein populärer Ansatz zur Erklärung spekulativer Attacken. Morris und Shin (1998) haben jedoch gezeigt, dass auch im Rahmen dieser Modelle eindeutige Gleichgewichte zu erwarten sind, sobald die Spekulanten verzerrte private Signale über die Fundamentaldaten erhalten. In dieser Arbeit verallgemeinern wir die Ergebnisse von Morris und Shin und zeigen, dass die Gleichgewichte selbst dann eindeutig sind, wenn Sunspot Variablen und individuelle Unsicherheit über Strategien zugelassen werden. Zudem analysieren wir, welchen Einfluss Transparenz auf die Wahrscheinlichkeit erfolgreicher Attacken hat. Für den Fall der Gleichverteilung verzerrter Signale zeigen wir, dass bei transparenter Geldpolitik ein Ausbruch solcher Attacken mit geringerer Wahrscheinlichkeit auftritt

Speculative Attacks

Models with multiple equilibria are a popular way to explain currency attacks. Morris and Shin (1998) have shown that, in the context of those models, unique equilibria may prevail once noisy private information is introduced. In this paper, we generalize the results of Morris and Shin to a broader class of probability distributions and show - using the technique of iterated elimination of dominated strategies - that uniqueness will hold, even if we allow for sunspots and individual uncertainty about strategic behavior of other agents. We provide a clear exposition of the logic of this model and we analyse the impact of transparency on the probability of a speculative attack. For the case of uniform distribution of noisy signals, we show that increased transparency of government policy reduces the likelihood of attacks

Flat-Bands on Partial Line Graphs -- Systematic Method for Generating Flat-Band Lattice Structures

We introduce a systematic method for constructing a class of lattice structures that we call ``partial line graphs''.In tight-binding models on partial line graphs, energy bands with flat energy dispersions emerge.This method can be applied to two- and three-dimensional systems. We show examples of partial line graphs of square and cubic lattices. The method is useful in providing a guideline for synthesizing materials with flat energy bands, since the tight-binding models on the partial line graphs provide us a large room for modification, maintaining the flat energy dispersions.Comment: 9 pages, 4 figure

USING SHIN LENGTH TO DETERMINE KICK PLATE POSITION OPTIMIZES SELECT SWIM START MECHANICS IN ELITE SWIMMERS

The track start kick plate position is often decided by the level of comfort of the swimmer. The purpose of this study was to use shin length as a measure to determine kick plate position and effects on performance. 20 elite swimmers performed 3 starts at 3 kick plate distances (\u3c shin length, shin length, and \u3e shin length). Differences in reaction time, block phase time (BT), flight phase time, flight distance, underwater phase time, time to the 15 m mark, knee flexion and ankle dorsiflexion angles were examined between the positions. BT was significantly different, (F(2,38)=4.264, p=.026). BT was lower when the kick plate distance was one shin’s length versus \u3c shin length (0.691+0.055 vs 0.715+0.056 sec) and \u3e shin length (0.691+0.055 vs 0.698+0.056 sec), p\u3c.05. Shin length is a quick and individualized measure that can be used by coaches to set the kick plate position without compromising performance

EFFECTS OF STANDARDIZING KICK PLATE POSITION ON TRACK START BIOMECHANICS IN ELITE SWIMMERS

Kick plate position in the track start is arbitrary but may influence performance. The purpose of this study was to investigate the influence of standardizing kick plate position based on shin length. 15 elite swimmers performed 3 starts at 3 kick plate positions (\u3c shin length, shin length, and \u3e shin length). Differences in reaction time (RT), block phase time, flight phase time, flight distance, underwater phase time, and time to the 15 m mark were examined between kick plate positions. Only RT was significantly different, (F(2,28)=4.713, p=.017). RT was lower when the kick plate distance was one shin’s length versus \u3c shin length (0.173+0.034vs 0.194+0.061 sec) and \u3e shin length (0.173+0.034 vs 0.195+0.047 sec),