Addressing the Quality Change Issue in the Consumer Price Index

macroeconomics, consumption, consumer price index, quality change, CPI bias, retail, substitution bias

Computing large market equilibria using abstractions

Computing market equilibria is an important practical problem for market design (e.g. fair division, item allocation). However, computing equilibria requires large amounts of information (e.g. all valuations for all buyers for all items) and compute power. We consider ameliorating these issues by applying a method used for solving complex games: constructing a coarsened abstraction of a given market, solving for the equilibrium in the abstraction, and lifting the prices and allocations back to the original market. We show how to bound important quantities such as regret, envy, Nash social welfare, Pareto optimality, and maximin share when the abstracted prices and allocations are used in place of the real equilibrium. We then study two abstraction methods of interest for practitioners: 1) filling in unknown valuations using techniques from matrix completion, 2) reducing the problem size by aggregating groups of buyers/items into smaller numbers of representative buyers/items and solving for equilibrium in this coarsened market. We find that in real data allocations/prices that are relatively close to equilibria can be computed from even very coarse abstractions

Neutralization of chemokines RANTES and MIG increases virus antigen expression and spinal cord pathology during Theiler's virus infection.

The role of chemokines during some viral infections is unpredictable because the inflammatory response regulated by these molecules can have two, contrasting effects-viral immunity and immunopathologic injury to host tissues. Using Theiler's virus infection of SJL mice as a model of this type of disease, we have investigated the roles of two chemokines-regulated on activation, normal T cell-expressed and secreted (RANTES) chemokine and monokine induced by IFN-gamma (MIG)-by treating mice with antisera that block lymphocyte migration. Control, infected mice showed virus persistence, mild inflammation and a small degree of demyelination in the white matter of the spinal cord at 6 weeks post-infection. Treatment of mice with RANTES antiserum starting at 2 weeks post-infection increased both viral antigen expression and the severity of inflammatory demyelination at 6 weeks post-infection. MIG antiserum increased the spread of virus and the proportion of spinal cord white matter with demyelination. Overall, viral antigen levels correlated strongly with the extent of pathology. At the RNA level, high virus expression was associated with low IL-2 and high IL-10 levels, and RANTES antiserum decreased the IL-2/IL-10 ratio. Our results suggest that RANTES and MIG participate in an immune response that attempts to restrict viral expression while limiting immunopathology and that anti-chemokine treatment poses the risk of exacerbating both conditions in the long term

Quantum Information Technology Based on Magnetic Excitation of Single Spin Dynamics

The single spin dynamics of a single electron was investigated theoretically by exciting the single electron magnetically. Different possibilities e.g quantum mechanical noise, inelastic collision emerged. To attain high performance of the quantum information technology, a low magnetization favoured the excitation process

Eggplants and Peaches: Understanding Emoji Usage on Grindr

This study focuses on how gay men communicate on the Grindr dating app. Prior research has been conducted on how gay men construct their online identities, however, few studies explore how gay men experience interactions online, negotiate their relationships with other men online, and perceive other users. The researcher conducted in-depth interviews with 20 men who use the Grinder app, a location-based dating app used by men who have sex with men. Additional data were collected by observing user profiles on the app, which is free and public. This comprehensive, qualitative study of gay men who use Grindr provides insights into identity construction, communication tactics, and users’ feelings about their encounters on the app