2,237,396 research outputs found
Competitive Foods
Describes the types of food items available to middle and high school students in forty California public secondary schools, as well as how well they match the nutrient standards defined in California's SB 12 legislation
Competitive Tiling
Competitive tiling consists of two players, a tile set, a region, and a non-negative integer d. Alice and Bob, our two players, alternate placing tiles on the untiled squares of the region. They play until no more tiles can be placed. Alice wins if at most d squares are untiled at the end of the game, and Bob wins if more than d squares are untiled. For given regions and tile sets we are interested in the smallest value of d such that Alice has a winning strategy. We call this the game tiling number. In this project, we focus on finding the game tiling number for the game played with dominoes on 2 x n rectangles, modified 2 x n rectangles, and rectangular annular regions
Competitive Priorities and Competitive Advantage in Jordanian Manufacturing
The purpose of this research was to explore and predict the relationship between the competitive priorities (quality, cost, flexibility and delivery) and the competitive advantage of firms in the Jordanian Industrial Sector. A population of 88 Jordanian manufacturing firms, registered on the Amman Stock Exchange, was targeted using a cross-sectional survey employing a questionnaire method of data collection. The results of the data analysis indicate a significant relationship between competitive priorities and competitive advantage. The research suggests that recognising and nurturing this relationship provides the master key for a firm to survive in a turbulent environment. Therefore, operational and marketing strategies should place emphasis on competitive priorities such as quality, cost, flexibility and delivery to achieve, develop and maintain competitive advantage. This study is one of the first to examine the relationship between the competitive priorities of Jordanian manufacturing firms and their competitive advantage
Competitive comparison in music: influences upon self-efficacy beliefs by gender
This study profiles gender differences in instrumental performance self-efficacy perceptions of high school students (Nâ=â87) over the course of a three-day orchestra festival in which students competed against one another for rank-based seating and then rehearsed and performed as a group. Reported self-beliefs rose significantly for the sample over the course of the festival. Self-efficacy beliefs of females were significantly lower than those of males before the seating audition and first rehearsal, but were no longer different by the midpoint of the festival. Survey free-response data were coded according to Bandura's (1997 Bandura, A. 1997. Self-efficacy: The Exercise of Control. New York: W. H. Freeman.) four sources of self-efficacy. A 52% drop in the frequency of student comments regarding competitive comparison appeared at the same point in which female self-efficacy beliefs were no longer different from those of males. Results support past research to suggest that males and females may respond differently to rank-based competition versus social support
Competitive Pressure: Competitive Dynamics as Reactions to Multiple Rivals
Competitive dynamics research has focused primarily on interactions between dyads of firms. Drawing on the awareness-motivation-capability framework and strategic group theory we extend this by proposing that firmsâ actions are influenced by perceived competitive pressure resulting from actions by several rivals. We predict that firmsâ action magnitude is influenced by the total number of rival actions accumulating in the market, and that this effect is moderated by strategic group membership. We test this using data on the German mobile telephony market and find them supported: the magnitude of firmâs actions is influenced by a buildup of actions by multiple rivals, and firms react more strongly to strategically similar rivals
Optimal Competitive Auctions
We study the design of truthful auctions for selling identical items in
unlimited supply (e.g., digital goods) to n unit demand buyers. This classic
problem stands out from profit-maximizing auction design literature as it
requires no probabilistic assumptions on buyers' valuations and employs the
framework of competitive analysis. Our objective is to optimize the worst-case
performance of an auction, measured by the ratio between a given benchmark and
revenue generated by the auction.
We establish a sufficient and necessary condition that characterizes
competitive ratios for all monotone benchmarks. The characterization identifies
the worst-case distribution of instances and reveals intrinsic relations
between competitive ratios and benchmarks in the competitive analysis. With the
characterization at hand, we show optimal competitive auctions for two natural
benchmarks.
The most well-studied benchmark measures the
envy-free optimal revenue where at least two buyers win. Goldberg et al. [13]
showed a sequence of lower bounds on the competitive ratio for each number of
buyers n. They conjectured that all these bounds are tight. We show that
optimal competitive auctions match these bounds. Thus, we confirm the
conjecture and settle a central open problem in the design of digital goods
auctions. As one more application we examine another economically meaningful
benchmark, which measures the optimal revenue across all limited-supply Vickrey
auctions. We identify the optimal competitive ratios to be
for each number of buyers n, that is as
approaches infinity
Competitive Gradient Descent
We introduce a new algorithm for the numerical computation of Nash equilibria
of competitive two-player games. Our method is a natural generalization of
gradient descent to the two-player setting where the update is given by the
Nash equilibrium of a regularized bilinear local approximation of the
underlying game. It avoids oscillatory and divergent behaviors seen in
alternating gradient descent. Using numerical experiments and rigorous
analysis, we provide a detailed comparison to methods based on \emph{optimism}
and \emph{consensus} and show that our method avoids making any unnecessary
changes to the gradient dynamics while achieving exponential (local)
convergence for (locally) convex-concave zero sum games. Convergence and
stability properties of our method are robust to strong interactions between
the players, without adapting the stepsize, which is not the case with previous
methods. In our numerical experiments on non-convex-concave problems, existing
methods are prone to divergence and instability due to their sensitivity to
interactions among the players, whereas we never observe divergence of our
algorithm. The ability to choose larger stepsizes furthermore allows our
algorithm to achieve faster convergence, as measured by the number of model
evaluations.Comment: Appeared in NeurIPS 2019. This version corrects an error in theorem
2.2. Source code used for the numerical experiments can be found under
http://github.com/f-t-s/CGD. A high-level overview of this work can be found
under http://f-t-s.github.io/projects/cgd
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