How Do Firms Exercise Unilateral Market Power? Evidence from a Bid-Based Wholesale Electricity Market

This paper uses the framework in Wolak (2003a,b and 2007) and data on half-hourly offer curves and market-clearing prices and quantities from the New Zealand wholesale electricity market over the period January 1, 2001 to June 30, 2007 to characterize how the four large suppliers in this imperfectly competitive industry exercise market power. To accomplish this we introduce half-hourly measures of the firm-level ability and incentive of an individual supplier to exercise unilateral market power that are derived from a simplified model of expected profit-maximizing offer behaviour in a multi-unit auction market. We then show that half-hourly market-clearing prices are highly correlated with the half-hourly values of the firm-level and firm-average measures of both the ability and incentive of the four large suppliers in New Zealand to exercise market power. We then present evidence consistent with the view that this increasing relationship between the ability or incentive of individual suppliers to exercise market power and higher market-clearing prices is caused by the four large suppliers submitting higher offer prices when they have a greater ability or incentive to exercise unilateral market power. We show that after controlling for changes in input fossil fuel prices and other factors that impact the opportunity cost of producing electricity during that half hour, each of the four suppliers submits a higher offer price into the wholesale market when it has a greater ability or incentive to exercise unilateral market power. To strengthen the case that this increasing relationship between market prices and the ability and incentive of each of the suppliers to exercise unilateral market power is actually caused by the four large suppliers exercising unilateral market power by changing their offer prices in response to their ability and incentive to exercise market power, we also perform a test of the implications of the null hypothesis that the four large suppliers behave as if they had no ability to exercise market power. We find strong evidence against this null hypothesis and instead find that these hypothesis testing results are consistent with the perspective that these suppliers are exercising all available unilateral market power.Classification-JEL:Unilateral Market power analysis,New Zealand,Electricity Market,multi-unit auction

Auxin-induced growth inhibition a natural consequence of two-point attachment

It is characteristic of a great number of biologically active substances that the responses which they elicit are twofold, low concentrations of the material promoting a particular activity, and higher concentrations inhibiting it. This is the case with the auxin-induced growth responses of plants. An active auxin such as indole acetic acid (IAA) brings about and is essential to growth in length of stems, hypocotyls and other plant organs including the Avena coleoptile

Participant Recruitment of African American College Students at an Historically Black College and University (HBCU): Challenges and Strategies for Health-Related Research

Lack of research participation among African Americans is problematic for population relevant health disparity research. The purpose of this paper is to identify and describe challenges and strategies in recruitment of African American college students for health related research being conducted at a small Historically Black College or University (HBCU). Upon completion of a recruitment and retention literature review, study investigators constructed and tested a culturally-specific, direct-appeal protocol to recruit participants. Major barriers to recruitment of African American college students included discrete sources of distrust, lack of understanding of the research process, and logistical concerns. Implementation of a culturally-specific, direct appeal protocol led to a significant improvement in recruitment and retention of student participants. It is imperative that researchers demystify scientific investigation as a first step towards building trust between themselves and target populations, particularly those from traditionally underrepresented groups. Reasons for distrust, a need for trust and trust building strategies are offered here

A survey of clinicians\u27 use of touch and body awareness in psychotherapy

A national purposive expert convenience sample of approximately 164 licensed, practicing mental health professionals responded to an anonymous online survey regarding the use of touch and body awareness in their treatment with clients. This study sought to answer the question of the effects of training, whether during the course of study to become a mental health professional or in a specific formalized body-oriented modality, on the attitudes and behavior of clinicians towards their use of touch and body awareness in psychotherapy treatment. The findings showed that training in the use of touch or body awareness does influence positive attitudes toward both. It was also found that training is an indicator of increased use of touch and body awareness by those clinicians surveyed

The effect of thinning on loblolly pine specific gravity as measured by the gamma densitometry technique

Study objectives were to correlate the gamma densitometry technique with conventional methods of measuring specific gravity and to use the gamma densitometer to analyze a thinned loblolly pine (Pinus taeda L.) stand for earlywood specific gravity, latewood specific gravity, average specific gravity, percent latewood and radial growth. In 1980 a 12 mm increment core was extracted from each of 160 sample trees in a 40 year old planted loblolly pine plantation which had been thinned in 1963 to residual basal area of 60 ft2/acre, 100 ft2/acre, and 140 ft2/acre; the control plot was unthinned and had a basal area of 158 ft2/acre. Two conventional specific gravity estimates were obtained for each core: (1) ovendry weight divided by green volume measured physically; (2) ovendry weight divided by green volume measured by water displacement. Average specific gravity values were also obtained by the gamma densitometer. The correlation of specific gravities between the gamma densitometer and the first conventional method was high: R2 = .76. The specific gravity correlation between the gamma densitometer and the second conventional method was not as high: R2 = .56. The specific gravity correlation between the two conventional methods was high: R2 = .73. The gamma densitometry technique also provided estimates of earlywood specific gravity, latewood specific gravity, as well as average specific gravity, percent latewood and radial growth. Significant differences were not found among basal area treatments for average specific gravity or percent latewood. However, earlywood specific gravity decreased significantly after thinning to 60 ft2/acre and 100 ft2 /acre. Latewood specific gravity increased significantly after thinning to a basal area 60 ft2/acre and 100 ft2/acre. Radial growth of trees in plots thinned to 60 ft2/acre and 100 ft2/acre was significantly greater after thinning than that of trees in the 140 ft2/acre and control plots

International Legal Scholarship in Canada

International law scholarship in Canada is largely limited to a small group of decentralized writers facing a vast and ill-defined field. In those areas in which significant work has been undertaken - the law of the sea, for example - Canadian scholarship is limited by a commitment to a national perspective rather than a recognition of the interests of the global community. The work is largely descriptive, and avoids a deeper theoretical analysis. International law is seen as a fringe discipline, and is presently unable to support the specialized effort necessary to produce the fundamental research that is badly needed if the significance of the area is to be recognize

Carbohydrate-electrolyte drink ingestion and skill performance during and after 2 hr of indoor tennis match play

Twenty-two tennis players were individually studied on 2 occasions. They performed a prematch skill test, a 2-hr tennis match against an equally ranked opponent, and a postmatch skill test. A carbohydrate-electrolyte (CHO-E; Lucozade Sport) or flavor-matched placebo-electrolyte (PL) beverage was administered in a double-blind fashion. During the trials, heart-rate and movement intensity were monitored, and the match was recorded for performance analysis. There were no differences in skill-test scores pre- to postmatch or between trials (154 ± 38 pre- and 160 ± 35 postmatch on PL, 155 ± 36 pre- and 165 ± 33 postmatch on CHO-E). CHO-E ingestion elevated blood glucose concentration throughout the match, and participants reported feeling more energetic (general activation) and more tense (high activation) 1 hr into the match than at baseline (p less than .05). Participants in the CHO-E trial spent more time in moderate-intensity activity and less time in low-intensity activity than on PL. Performance analysis revealed that CHO-E ingestion increased overall serve success (M ± SD, 68% ± 7% for CHO-E vs. 66% ± 7% for PL; p less than .05) and success of first serves (65% ± 9% for CHO-E, 61% ± 7% for PL; p less than .01) and serves to the advantage side (70% ± 9% for CHO-E, 66% ± 7% for PL; p less than .05). Return success was greater during the second set of the match (p less than .05) in the CHO-E trial. Differences in serve and return success were not associated with blood glucose response to CHO or player abilit