Rigid prices: evidence from U.S. scanner data

This paper uses over two years of weekly scanner data from two small US cities to characterize time and state dependence of grocers' pricing decisions. In these data, the probability of a nominal adjustment declines with the time since the last price change. This reflects differences over time in the flexibility of prices charged by a single store for a given good. We also detect state dependence: The probability of a nominal adjustment is highest when a store's price substantially differs from the average of other stores. However, extreme prices typically reflect the selling store's recent nominal adjustments rather than changes in other stores' prices.Prices

Measurement based entanglement under conditions of extreme photon loss

The act of measuring optical emissions from two remote qubits can entangle them. By demanding that a photon from each qubit reaches the detectors, one can ensure than no photon was lost. But the failure rate then rises quadratically with loss probability. In [1] this resulted in 30 successes per billion attempts. We describe a means to exploit the low grade entanglement heralded by the detection of a lone photon: A subsequent perfect operation is quickly achieved by consuming this noisy resource. We require only two qubits per node, and can tolerate both path length variation and loss asymmetry. The impact of photon loss upon the failure rate is then linear; realistic high-loss devices can gain orders of magnitude in performance and thus support QIP.Comment: Contains an extension of the protocol that makes it robust against asymmetries in path length and photon los

Regrowth: A Paradise Rec Center

Ben Campbell’s Regrowth Recreation Center is located on a site overlooking the new park in the center of the proposed East Village. Seeking to encourage exercise and healthy lifestyles, the center has areas for weight training, classroom instruction for yoga and other types of exercise, a basketball court, and both an indoor and outdoor pool. The building is conceived as a series of arms extending from a central core. A café and retail shop space on the ground floor help integrate the center with the new downtown

Adaptive strategies for graph state growth in the presence of monitored errors

Graph states (or cluster states) are the entanglement resource that enables one-way quantum computing. They can be grown by projective measurements on the component qubits. Such measurements typically carry a significant failure probability. Moreover, they may generate imperfect entanglement. Here we describe strategies to adapt growth operations in order to cancel incurred errors. Nascent states that initially deviate from the ideal graph states evolve toward the desired high fidelity resource without impractical overheads. Our analysis extends the diagrammatic language of graph states to include characteristics such as tilted vertices, weighted edges, and partial fusion, which arise from experimental imperfections. The strategies we present are relevant to parity projection schemes such as optical `path erasure' with distributed matter qubits.Comment: 4 pages, 4 figures. Typos corrected, nicer figures, neater notation and better rea

Androgen Receptor and Vasopressin Receptor (AVPR1a) Genetic Polymorphisms are not associated with Marital Status or Fertility among Ariaal Men of Northern Kenya

A growing body of scholarship implicates testosterone and vasopressin in male reproductive behavior, including in humans. Since hormones exert their effects through their respective receptors, an open question has been whether genetic polymorphisms in the androgen receptor and vasopressin 1a receptor (AVPR1a) impact human male social behavior. Here, we sought to test for associations between polymorphisms in the coding region of the androgen receptor and promoter region of AVPR1a in relation to marital status and fertility among pastoralist Ariaal men of northern Kenya. None of the three polymorphisms were related to marital status (single, monogamously married, polygynously married) or fertility (number of current living children). We discuss these null findings in light of existing data

Housing Supply and the Common Wealth

It’s a powerful thing to mark the fiftieth anniversary of the Fair Housing Act of 1968, something that actually happened and has actually had an effect. I grew up in segregated Virginia, so I have a pretty powerful sense of the passage of time here. It’s given us the opportunity today to review and mark human progress, to take stock of where we are and to identify the efforts and issues of our time. The victories here have changed the nation, and the task is still daunting