scholarly journals Optimal Patrol of a Perimeter

2021 ◽  
Author(s):  
Kyle Y. Lin
Keyword(s):  
Detection Probability ◽  
Conventional Wisdom ◽  
Optimal Detection ◽  
Time Points ◽  
Long Run

A defender dispatches patrollers to circumambulate a perimeter to guard against potential attacks. The defender decides on the time points to dispatch patrollers and each patroller’s direction and speed, as long as the long-run rate at which patrollers are dispatched is capped at some constant. An attack at any point on the perimeter requires the same amount of time, during which it will be detected by each passing patroller independently with the same probability. The defender wants to maximize the probability of detecting an attack before it completes, while the attacker wants to minimize it. We study two scenarios, depending on whether the patrollers are undercover or wear a uniform. Conventional wisdom would suggest that the attacker gains advantage if he can see the patrollers going by so as to time his attack, but we show that the defender can achieve the same optimal detection probability by carefully spreading out the patrollers probabilistically against a learning attacker.

scholarly journals Using Analytics To Challenge Conventional Baseball Wisdom

2015 ◽  
Vol 8 (1) ◽  
pp. 11-20
Author(s):  
Loren Paul Rees ◽  
Terry R. Rakes ◽  
Jason K. Deane
Keyword(s):  
Initial Study ◽  
Conventional Wisdom ◽  
Long Run

Baseball, like most other sports, has a set of tenets that began early and have survived virtually unquestioned.  Modern analytics gives us an opportunity to examine some of these long-held tenets to see if they were founded on solid evidence.  This research examines some common baseball wisdom through an initial study utilizing simulation.  In particular, the profiles of several baseball teams are constructed and various factors are examined by simulating ten baseball seasons under various configurations with the different teams. Contrary to conventional wisdom, a batting order where high-average hitters bat third in a lineup and the team’s best power hitter bats cleanup (fourth), for example, does not necessarily generate the most runs per game over the long run.  Moreover, high-average hitters with less power can generate more runs per game than power hitters with lesser averages.  Finally, it appears that hitters who perform well with runners in scoring position are more influential in helping their team score more runs than even more powerful or higher average hitters who do not produce as frequently in such cases.  Players with lower star profiles, but who rise to the occasion with runners in scoring position, can often be purchased by baseball clubs that have a more constrained payroll; teams that are less well-off financially may thus purchase or trade for these hitters and still field a team with a competitive level of high run production.

Two-Way Substitutable Inventory System with N–Policy

2010 ◽  
pp. 253-260
Author(s):  
N. Anbazhagan
Keyword(s):  
Inventory System ◽  
Inventory Level ◽  
Unit Size ◽  
Cost Rate ◽  
Continuous Review ◽  
Time Points ◽  
Stochastic Inventory ◽  
Ordering Policy ◽  
Long Run ◽  
Operational Characteristics

This article presents a two commodity stochastic inventory system under continuous review. The maximum storage capacity for the i-th item is fixed as Si (i = 1, 2). It is assumed that demand for the i-the commodity is of unit size and demand time points form Poisson distribution with parameter i = 1, 2. The reorder level is fixed as si for the i-th commodity (i = 1, 2) and the ordering policy is to place order for items for the i-th commodity (i = 1, 2) when both the inventory levels are less than or equal to their respective reorder levels. The lead time is assumed to be exponential. The two commodities are assumed to be substitutable. That is, if the inventory level of one commodity reaches zero, then any demand for this commodity will be satisfied by the item of the other commodity. If no substitute is available, then this demand is backlogged up to a certain level Ni, (i = 1, 2) for the i-th commodity. Whenever the inventory level reaches Ni, (i = 1, 2), an order for Ni items is replenished instantaneously. For this model, the limiting probability distribution for the joint inventory levels is computed. Various operational characteristics and expression for long run total expected cost rate are derived.

New Factors of Stability in Soviet Collective Leadership

1967 ◽  
Vol 19 (4) ◽  
pp. 563-581 ◽  
Author(s):  
Jerome M. Gilison
Keyword(s):  
Soviet Union ◽  
Conventional Wisdom ◽  
Historical Evidence ◽  
Collective Leadership ◽  
Power Drive ◽  
Nikita Khrushchev ◽  
The Soviet Union ◽  
Long Run ◽  
New Phase ◽  
Leadership Pattern

With the reluctant retirement of Nikita Khrushchev, the Soviet Union entered a new phase of collective leadership. Past experience with such periods has led many Western specialists to expect that the collective leadership pattern will lead to the emergence of a single leader, who will hold preponderant power and who will seek to consolidate and strengthen that power, ultimately acquiring something approaching dictatorial authority. The assumptions of this “conventional wisdom” (to borrow a phrase from John Galbraith) are that (i) there is something inherently unstable in a collective leadership pattern, given Soviet conditions; (2) the personal ambitions and power drive of Soviet leaders prevent, in the long run, their acceptance of a situation of shared power; and (3) historical evidence of past breakdowns of collective leadership is applicable to present conditions.

Human Rights and Development: Complementary or Competing Concerns?

1984 ◽  
Vol 36 (2) ◽  
pp. 255-283 ◽  
Author(s):  
Jack Donnelly
Keyword(s):  
Human Rights ◽  
Rapid Development ◽  
Conventional Wisdom ◽  
Political Rights ◽  
Luxury Goods ◽  
Long Run ◽  
The Sixties ◽  
Civil And Political Rights ◽  
Economic Equity ◽  
Theoretical Considerations

The conventional wisdom of the sixties and early seventies held that, except in the very long run, rapid development and human rights are competing concerns. Needs satisfaction, income equality, and civil and political rights were regularly held to be luxury goods. An examination of the development experiences of Brazil and South Korea, however, shows much of this conventional wisdom to have been mistaken. Rapid growth and development can be achieved without sacrificing social and economic equity. Furthermore, theoretical considerations suggest that even civil and political rights are more compatible with sustained rapid development than is frequently recognized.

scholarly journals Børns koloniserede arbejde

2006 ◽  
Vol 14 (2) ◽  
pp. 25-36
Author(s):  
Jens Qvortrup
Keyword(s):  
Child Poverty ◽  
Modern Society ◽  
Division Of Labour ◽  
Conventional Wisdom ◽  
Low Fertility ◽  
Industrial Society ◽  
Public Practice ◽  
Long Run ◽  
Children’S Work ◽  
The One

Jens Qvortrup: The colonization of children’s work This article develops both historical and theoretical arguments against the flawed logic of a conventional wisdom. This conventional wisdom is the notion that while children in pre-industrial society were actively taking part in work, the scholarised children in modern society are merely preparing themselves to become contributors to the social fabric. Combined with family ideology, this view has implications for low fertility rates and greater risk of poverty for children and their families. The modern schooling marathon should be understood as a continuation of children’s organic participation in activities deemed necessary by the mode of production, reflecting an historical shift from manual to mental child work. This understanding of children’s schoolwork logically implies that children are part of a societal division of labour, and therefore have legitimate claims to societal resources and public economic responsibility. Putting these insights into public practice would, on the one hand, alleviate the economic burdens of parents and the risk of child poverty, and, on the other, create incentives for increased fertility. In the long run this would contribute to the solution of the impending pension crisis. And too, it would help reestablish the intergenerational balance.

scholarly journals The Size‐Power Tradeoff in HAR Inference

Econometrica ◽  
2021 ◽  
Vol 89 (5) ◽  
pp. 2497-2516 ◽  
Author(s):  
Eben Lazarus ◽  
Daniel J. Lewis ◽  
James H. Stock
Keyword(s):  
Time Series ◽  
Closed Form ◽  
Kernel Estimation ◽  
Rejection Rate ◽  
Critical Values ◽  
Conventional Wisdom ◽  
Time Series Regression ◽  
Truncation Parameter ◽  
Long Run ◽  
Multivariate Location

Heteroskedasticity‐ and autocorrelation‐robust (HAR) inference in time series regression typically involves kernel estimation of the long‐run variance. Conventional wisdom holds that, for a given kernel, the choice of truncation parameter trades off a test's null rejection rate and power, and that this tradeoff differs across kernels. We formalize this intuition: using higher‐order expansions, we provide a unified size‐power frontier for both kernel and weighted orthonormal series tests using nonstandard “fixed‐ b” critical values. We also provide a frontier for the subset of these tests for which the fixed‐ b distribution is t or F. These frontiers are respectively achieved by the QS kernel and equal‐weighted periodogram. The frontiers have simple closed‐form expressions, which show that the price paid for restricting attention to tests with t and F critical values is small. The frontiers are derived for the Gaussian multivariate location model, but simulations suggest the qualitative findings extend to stochastic regressors.

Duffy antigen / receptor for chemokines correlates with inflammatory reaction in rats with venous hypertension: implication for the pathogenesis of primary chronic venous disease

VASA ◽  
2014 ◽  
Vol 43 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Weibin Huang ◽  
Weiwei Qin ◽  
Lei Lv ◽  
Haoyv Deng ◽  
Hao Zhang ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Early Stage ◽  
Antigen Receptor ◽  
Venous Hypertension ◽  
Skin Tissue ◽  
Chronic Venous Disease ◽  
Venous Disease ◽  
Dependent Manner ◽  
Time Points ◽  
Duffy Antigen

Background: Duffy antigen / receptor for chemokines (DARC) possesses high affinity for several chemokine subgroups of CC and CXC. Although DARC has been shown to play a role in many inflammatory diseases, its effect on chronic venous disease (CVD) remains unidentified. We explored whether the expression of DARC in skin tissue was activated under venous hypertension as well as the relationships between DARC and inflammation. Materials and methods: The inflammation in a rat model of venous hypertension caused by a femoral arterial-venous fistula (AVF) was studied. At specified intervals the pressure in the femoral veins was recorded within 42 days. Hindlimb skin specimens were harvested at different time points. The expressions of DARC, interleukin-8 (IL-8), and monocyte chemotactic protein-1 (MCP-1) in skin tissue were examined. Mononuclear cells infiltrated in skin tissue were detected. Results: Femoral venous pressures in AVF groups increased significantly at different time points (P < 0.01). DARC was expressed in skin tissue and its expression level increased significantly in AVF groups from the 7nd day on and was enhanced in a time-dependent manner within 42 days (P < 0.05). Meanwhile, both MCP-1 and IL-8 had higher levels, accompanied by increased mononuclear cells infiltrating into skin tissue (P < 0.05). Conclusions: A rat AVF model which can maintain venous hypertension for at least 42 days is competent for researching the pathogenesis of CVD. DARC, which plays a role in the inflammation of skin tissue under venous hypertension, may become a new molecular target for diagnosis and treatment of CVD at a very early stage.

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