860 research outputs found
ZIP60: Further Explorations in the Evolutionary Design of Trader Agents and Online Auction-Market Mechanisms
No full textThe “ZIP” adaptive automated trading algorithm has been demonstrated to outperform human traders in experimental studies of continuous double auction (CDA) markets populated by mixtures of human and “software robot” traders. Previous papers have shown that values of the eight parameters governing behavior of ZIP traders can be automatically optimized using a genetic algorithm (GA), and that markets populated by GA-optimized traders perform better than those populated by ZIP traders with manually-set parameter values. This paper introduces a more sophisticated version of the ZIP algorithm, called “ZIP60”, which requires the values of 60 parameters to be set correctly. ZIP60 is shown here to produce significantly better results in comparison to the original ZIP algorithm (called “ZIP8” hereafter) when a GA is used to search the 60-dimensional parameter space. It is also demonstrated here that this works best when the GA itself has control over the dimensionality of the search-space, allowing evolution to guide the expansion of the search-space up from 8 parameters to 60 via intermediate steps. Principal component analysis of the best evolved ZIP60 parameter-sets establishes that no ZIP8 solutions are embedded in the 60-dimensional space. Moreover, some of the results and analysis presented here cast doubt on previously-published ZIP8 results concerning the evolution of new ‘hybrid’ auction mechanisms that appeared to be improvements on the CDA: it now seems likely that those results were actually consequences of the relative lack of sophistication in the original ZIP8 algorithm, because “hybrid” mechanisms occur much less frequently when ZIP60s are used
hpDJ: An automated DJ with floorshow feedback
No full textMany radio stations and nightclubs employ Disk-Jockeys (DJs) to provide a continuous uninterrupted stream or “mix” of dance music, built from a sequence of individual song-tracks. In the last decade, commercial pre-recorded compilation CDs of DJ mixes have become a growth market. DJs exercise skill in deciding an appropriate sequence of tracks and in mixing 'seamlessly' from one track to the next. Online access to large-scale archives of digitized music via automated music information retrieval systems offers users the possibility of discovering many songs they like, but the majority of consumers are unlikely to want to learn the DJ skills of sequencing and mixing. This paper describes hpDJ, an automatic method by which compilations of dance-music can be sequenced and seamlessly mixed by computer, with minimal user involvement. The user may specify a selection of tracks, and may give a qualitative indication of the type of mix required. The resultant mix can be presented as a continuous single digital audio file, whether for burning to CD, or for play-out from a personal playback device such as an iPod, or for play-out to rooms full of dancers in a nightclub. Results from an early version of this system have been tested on an audience of patrons in a London nightclub, with very favourable results. Subsequent to that experiment, we designed technologies which allow the hpDJ system to monitor the responses of crowds of dancers/listeners, so that hpDJ can dynamically react to those responses from the crowd. The initial intention was that hpDJ would monitor the crowd’s reaction to the song-track currently being played, and use that response to guide its selection of subsequent song-tracks tracks in the mix. In that version, it’s assumed that all the song-tracks existed in some archive or library of pre-recorded files. However, once reliable crowd-monitoring technology is available, it becomes possible to use the crowd-response data to dynamically “remix” existing song-tracks (i.e, alter the track in some way, tailoring it to the response of the crowd) and even to dynamically “compose” new song-tracks suited to that crowd. Thus, the music played by hpDJ to any particular crowd of listeners on any particular night becomes a direct function of that particular crowd’s particular responses on that particular night. On a different night, the same crowd of people might react in a different way, leading hpDJ to create different music. Thus, the music composed and played by hpDJ could be viewed as an “emergent” property of the dynamic interaction between the computer system and the crowd, and the crowd could then be viewed as having collectively collaborated on composing the music that was played on that night. This en masse collective composition raises some interesting legal issues regarding the ownership of the composition (i.e.: who, exactly, is the author of the work?), but revenue-generating businesses can nevertheless plausibly be built from such technologies
Complicated and overlapping motives : The political life and art of Cliff Rowe 1904 - 1989
Get PDFThis thesis critically reappraises the life and work of Cliff Rowe (1904–1989), an artist and Communist whose six-decade career has been largely overlooked in British art history. Best known as a founder of the Artists’ International – later the Artists’ International Association (AIA) - and a lifelong member of the Communist Party of Great Britain (CPGB), Rowe’s career exemplifies the tensions of socially engaged art. His work reveals a constant negotiation between artistic integrity, political commitment, and historical circumstance, offering insights still relevant to debates on art and political activism. The study draws on Rowe’s journals, letters, essays, and autobiographical fragments, supplemented by oral histories, archival sources, and secondary scholarship. Acknowledging the author’s personal connection as Rowe’s son-in-law, it reflects on the ethical and methodological challenges of writing from within a family, while showing how biography can illuminate broader cultural and political forces. Rowe’s art is treated as both visual testimony and historical evidence, revealing the interplay between personal conviction, ideological discipline, and audience reception. The chapters proceed chronologically but are also thematic. Early chapters explore Rowe’s formative years, his transformative stay in the Soviet Union, and his role in establishing the Artists’ International and AIA. Subsequent chapters examine his wartime activities, his struggles with CPGB cultural policy during the Cold War, and the crises of the 1950s that forced him to reconsider his political and artistic commitments. An epilogue reflects on his later attempts to redefine socialist art outside Party orthodoxy. By situating Cliff Rowe within the context of twentieth-century British cultural politics, this study contributes to scholarship on the CPGB, the AIA, and the broader history of left-wing art, while also highlighting the contemporary significance of attempts to reconcile artistic practice with political ideals. It argues that Rowe’s career resists simple categorisation and should be understood as symptomatic of the dilemmas faced by many left-wing artists and writers during this period. Neither a straightforward Party propagandist nor an apolitical practitioner, Rowe embodied the ‘complicated and overlapping motives’ that characterised politically engaged cultural work. His persistence, despite compromises and contradictions, brings into focus the tensions between hope and disillusionment, conviction and doubt that shaped the experience of artists and intellectuals on the left. The choices he made illuminate the broader difficulty of artistic and political commitment in conditions where clear moral courses of action were not always available, and compromise was sometimes unavoidable
Letter from Cliff [Uyeda] to Michi Weglyn, July 20, 1987
No full textA letter from "Cliff" [Clifford I. Uyeda] to Michi Weglyn criticizing the 1987 book "They Call Me Moses Masaoka" by Mike Masaoka and Bill Hosokawa. The author of the letter also describes internal conflict on the national board of the Japanese American Citizens League (JACL).These materials are from box 73 and 74 of the Frank Chin Papers. The Frank Chin Papers contain personal and professional correspondence between Frank Chin and Michi Weglyn relating to particular projects on which either author was working as well as files related to the Day of Remembrance Tribute to Michi Weglyn
Writing for fun: Interview with Peter Corris, author of the Cliff Hardy detective novels
No full textAustralian author Peter Corris (1942–) talks about his transformation from anxious academic to lighthearted writer of detective novels, especially the Cliff Hardy series. He reveals the real-life models he used in creating Cliff Hardy, the authors he took as role models, and where he gets ideas for the plots and settings
Cliff Retreat Induced by Series of Storms at Miȩdzyzdroje (Poland)
No full textIn Miȩdzyzdroje, a coastal town in Poland, significant cliff retreat has been observed in recent times. It used to be considered mainly a response to storm events with particularly high water levels and wave energy. However, morphology of cliff coasts is shaped not only by the most extreme storm surges or by a number of accompanying processes such as precipitation. Much wider effects are now being linked to the occurrence of series of subsequent storms. This research uses a set of five terrestrial LiDAR surveys carried out between November 2016 and April 2017 to determine short-term cliff erosion associated with two major storm surges and several smaller storms. The surveys covered the whole cliff profile as well as the topography of the adjacent beach. Results indicate a considerable reduction in beach levels as a first important effect. Frequency of the storm events prevented the beach from recovering between the surges, allowing the waves to directly attack the cliff base. Consequently, the cliff foot line retreated up to 4.7 m. This resulted in an erosion volume exceeding 25.000 m within 5 sections of the coastal cliff analysed, which are 500 m long in total. This work demonstrates that the development of the coastline is not only directly linked with the rate of erosion at given storm parameters. More importantly, the frequency of extreme events has to be considered.Hydraulic Structures and Flood Ris
Christchurch New Zealand cliff hike
No full textFor this 8-minute documentary, the author lugged a video camera and gave a running commentary of a hike from the Scarborough area of Christchurch, New Zealand up a cliff with great scenic beauty. Not long afterward the author saw on TV in Japan that the cliff with all its vegetation and bird nests had crashed into the ocean during a major Christchurch earthquake
Alice and Cliff Donahue
No full textPhotograph - Friends of Alice B. and William Clifford Donahue, Athabasca, Alberta. Seated, left to right: Cliff Donahue, Joe Mikkelsen, Beryl Mikkelsen, and Marge Logan. Standing, left to right: Don Logan, Alice B. Donahue, Aaron Jones, Lorene Jones, and Beatrice Par
Evidencing the "robot phase transition" in experimental human-algorithmic markets
Get PDFJohnson, Zhao, Hunsader, Meng, Ravindar, Carran, and Tivnan (2012) recently suggested the existence of a phase transition in the dynamics of financial markets in which there is free interaction between human traders and algorithmic trading systems ("robots"). Above a particular time-threshold, humans and robots trade with one another; below the threshold all transactions are robot-to-robot. We refer to this abrupt system transition as the "robot phase transition". Here, we conduct controlled experiments where human traders interact with 'robot' trading agents in minimal models of electronic financial markets to see if correlates of the two regimes suggested by Johnson et al. (2012) occur in such laboratory conditions. Our results indicate that when trading robots act on a super-human timescale, the market starts to fragment, with statistically lower human-robot interactions than we would expect from a fully mixed market. We tentatively conclude that this is the first empirical evidence for the robot phase transition occurring under controlled experimental conditions
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