Liquid identities: Mecca Cola versus Coca-Cola

The Mecca Cola drink combines in its brand name two contrasting iconic images: one signifies 'authenticity', whereas the other signifies a 'commodity'. The conspicuous juxtaposition of 'Mecca' and 'Cola' and their hyphenization evokes the question: what is becoming of 'authenticity' in a thoroughly commodified world society? This article proposes that a distinction ought to be drawn between the effects of commodification on two distinct levels: the structural and symbolic. Whereas commodification homogenizes structurally, it heterogenizes symbolically. This article maintains that while symbolically Mecca Cola is antagonistic to Coca-Cola, structurally it is a case of an appropriation of the former by the latter. Mecca Cola thus attests to a structural 'Cola-ization' accompanied by a symbolic 'Mecca-ization' of current world cultures

George Ritzer and Paul Dean, Globalization: a Basic Text.

Book Revie

Incremental Refinements and Multiple Descriptions with Feedback

It is well known that independent (separate) encoding of K correlated sources may incur some rate loss compared to joint encoding, even if the decoding is done jointly. This loss is particularly evident in the multiple descriptions problem, where the sources are repetitions of the same source, but each description must be individually good. We observe that under mild conditions about the source and distortion measure, the rate ratio Rindependent(K)/Rjoint goes to one in the limit of small rate/high distortion. Moreover, we consider the excess rate with respect to the rate-distortion function, Rindependent(K, M) - R(D), in M rounds of K independent encodings with a final distortion level D. We provide two examples - a Gaussian source with mean-squared error and an exponential source with one-sided error - for which the excess rate vanishes in the limit as the number of rounds M goes to infinity, for any fixed D and K. This result has an interesting interpretation for a multi-round variant of the multiple descriptions problem, where after each round the encoder gets a (block) feedback regarding which of the descriptions arrived: In the limit as the number of rounds M goes to infinity (i.e., many incremental rounds), the total rate of received descriptions approaches the rate-distortion function. We provide theoretical and experimental evidence showing that this phenomenon is in fact more general than in the two examples above.Comment: 62 pages. Accepted in the IEEE Transactions on Information Theor

An Orthogonality Principle for Select-Maximum Estimation of Exponential Variables

It was recently proposed to encode the one-sided exponential source X via K parallel channels, Y1, ..., YK , such that the error signals X - Yi, i = 1,...,K, are one-sided exponential and mutually independent given X. Moreover, it was shown that the optimal estimator \hat{Y} of the source X with respect to the one-sided error criterion, is simply given by the maximum of the outputs, i.e., \hat{Y} = max{Y1,..., YK}. In this paper, we show that the distribution of the resulting estimation error X - \hat{Y} , is equivalent to that of the optimum noise in the backward test-channel of the one-sided exponential source, i.e., it is one-sided exponentially distributed and statistically independent of the joint output Y1,...,YK.Comment: 5 pages. Submitted to ISI

Lattice strategies for the dirty multiple access channel

A generalization of the Gaussian dirty-paper problem to a multiple access setup is considered. There are two additive interference signals, one known to each transmitter but none to the receiver. The rates achievable using Costa’s strategies (i.e. by a random binning scheme induced by Costa’s auxiliary random variables) vanish in the limit when the interference signals are strong. In contrast, it is shown that lattice strategies (“lattice precoding”) can achieve positive rates independent of the interferences, and in fact in some cases- which depend on the noise variance and power constraints- they are optimal. In particular, lattice strategies are optimal in the limit of high SNR. It is also shown that the gap between the achievable rate region and the capacity region is at most 0.167 bit. Thus, the dirty MAC is another instance of a network setup, like the Korner-Marton modulo-two sum problem, where linear coding is potentially better than random binning. Lattice transmission schemes and conditions for optimality for the asymmetric case, where there is only one interference which is known to one of the users (who serves as a “helper ” to the other user), and for the “common interference ” case are also derived. In the former case the gap between the helper achievable rate and its capacity is at most 0.085 bit

On Reporting the Onset of the Intention to Move

In 1965, Hans Kornhuber and Luder Deecke made a discovery that greatly influenced the study of voluntary action. Using electroencephalography (EEG), they showed that when aligning some tens of trials to movement onset and averaging, a slowly decreasing electrical potential emerges over central regions of the brain. It starts 1 second ( s) or so before the onset of the voluntary action1 and continues until shortly after the action begins. They termed this the Bereitschaftspotential, or readiness potential (RP; Kornhuber & Deecke, 1965).2 This became the first well-established neural marker of voluntary action. In that, the RP allowed for more objective research on voluntary action rather than its previous dependence on subjective introspection. Two decades later, the RP captured the attention of the wider neuroscience community as well as of philosophers, legal scholars, and laypeople. This is because it was associated with a key question in the debate on free will: Is human voluntary action caused by the conscious intention to act? Or does the conscious experience only follow unconscious neural activity, which is the true origin of that action, and over which humans have only-limited immediate control?https://digitalcommons.chapman.edu/psychology_books/1019/thumbnail.jp