Items of some interest…

These are my recent Pin​board​.in links:

Items of some interest…

These are my recent Pin​board​.in links:

  • [1106.1804] A Crit­i­cal Assess­ment of Bench­mark Com­par­i­son in Planning

    “Recent trends in plan­ning research have led to empir­i­cal com­par­i­son becom­ing com­mon­place. The field has started to set­tle into a method­ol­ogy for such com­par­isons, which for obvi­ous prac­ti­cal rea­sons requires run­ning a sub­set of plan­ners on a sub­set of prob­lems. In this paper, we char­ac­ter­ize the method­ol­ogy and exam­ine eight implicit assump­tions about the prob­lems, plan­ners and met­rics used in many of these com­par­isons. The prob­lem assump­tions are: PR1) the per­for­mance of a gen­eral pur­pose plan­ner should not be penalized/​biased if exe­cuted on a sam­pling of prob­lems and domains, PR2) minor syn­tac­tic dif­fer­ences in rep­re­sen­ta­tion do not affect per­for­mance, and PR3) prob­lems should be solv­able by STRIPS capa­ble plan­ners unless they require ADL. The plan­ner assump­tions are: PL1) the lat­est ver­sion of a plan­ner is the best one to use, PL2) default para­me­ter set­tings approx­i­mate good per­for­mance, and PL3) time cut-​​offs do not unduly bias out­come. The met­rics assump­tions are: M1) per­for­mance degrades sim­i­larly for each plan­ner when run on degraded run­time envi­ron­ments (e.g., machine plat­form) and M2) the num­ber of plan steps dis­tin­guishes per­for­mance. We find that most of these assump­tions are not sup­ported empir­i­cally; in par­tic­u­lar, that plan­ners are affected dif­fer­ently by these assump­tions. We con­clude with a call to the com­mu­nity to devote research resources to improv­ing the state of the prac­tice and espe­cially to enhanc­ing the avail­able bench­mark problems.”

    plan­ning bench­mark­ing algo­rithms horse-​​races engineering-​​design operations-​​research nudge-​​targets
  • [1108.4361] The rela­tion­ship between acquain­tance­ship and coau­thor­ship in sci­en­tific col­lab­o­ra­tion networks

    “This arti­cle exam­ines the rela­tion­ship between acquain­tance­ship and coau­thor­ship pat­terns in a multi-​​disciplinary, multi-​​institutional, geo­graph­i­cally dis­trib­uted research cen­ter. Two social net­works are con­structed and com­pared: a net­work of coau­thor­ship, rep­re­sent­ing how researchers write arti­cles with one another, and a net­work of acquain­tance­ship, rep­re­sent­ing how those researchers know each other on a per­sonal level, based on their responses to an online sur­vey. Sta­tis­ti­cal analy­ses of the topol­ogy and com­mu­nity struc­ture of these net­works point to the impor­tance of small-​​scale, local, per­sonal net­works pred­i­cated upon acquain­tance­ship for accom­plish­ing col­lab­o­ra­tive work in sci­en­tific communities.”

    academic-​​culture network-​​theory cita­tion social-​​networks
  • [1108.4223] The set-​​theoretic multiverse

    “The mul­ti­verse view in set the­ory, intro­duced and argued for in this arti­cle, is the view that there are many dis­tinct con­cepts of set, each instan­ti­ated in a cor­re­spond­ing set-​​theoretic uni­verse. The uni­verse view, in con­trast, asserts that there is an absolute back­ground set con­cept, with a cor­re­spond­ing absolute set-​​theoretic uni­verse in which every set-​​theoretic ques­tion has a def­i­nite answer. The mul­ti­verse posi­tion, I argue, explains our expe­ri­ence with the enor­mous diver­sity of set-​​theoretic pos­si­bil­i­ties, a phe­nom­e­non that chal­lenges the uni­verse view. In par­tic­u­lar, I argue that the con­tin­uum hypoth­e­sis is set­tled on the mul­ti­verse view by our exten­sive knowl­edge about how it behaves in the mul­ti­verse, and as a result it can no longer be set­tled in the man­ner for­merly hoped for.”

    math­e­mat­ics mathematical-​​criticism looking-​​forward-​​to-​​understanding-​​this-​​someday pragmatism-it-ain’t
  • [1102.1934] The struc­ture of the Arts & Human­i­ties Cita­tion Index: A map­ping on the basis of aggre­gated cita­tions among 1,157 journals

    “Using the Arts & Human­i­ties Cita­tion Index (A&HCI) 2008, we apply map­ping tech­niques pre­vi­ously devel­oped for map­ping jour­nal struc­tures in the Sci­ence and Social Sci­ence Cita­tion Indices. Cita­tion rela­tions among the 110,718 records were aggre­gated at the level of 1,157 jour­nals spe­cific to the A&HCI, and the jour­nal struc­tures are ques­tioned on whether a cog­ni­tive struc­ture can be recon­structed and visu­al­ized. Both cosine-​​normalization (bot­tom up) and fac­tor analy­sis (top down) sug­gest a divi­sion into approx­i­mately twelve sub­sets. The rela­tions among these sub­sets are explored using var­i­ous visu­al­iza­tion tech­niques. How­ever, we were not able to retrieve this struc­ture using the ISI Sub­ject Cat­e­gories, includ­ing the 25 cat­e­gories which are spe­cific to the A&HCI. We dis­cuss options for val­i­da­tion such as against the cat­e­gories of the Human­i­ties Indi­ca­tors of the Amer­i­can Acad­emy of Arts and Sci­ences, the panel struc­ture of the Euro­pean Ref­er­ence Index for the Human­i­ties (ERIH), and com­pare our results with the cur­ricu­lum orga­ni­za­tion of the Human­i­ties Sec­tion of the Col­lege of Let­ters and Sci­ences of UCLA as an exam­ple of insti­tu­tional organization.”

    network-​​theory citation-​​networks human­i­ties academic-​​culture quantitative-​​humanities
  • [1108.4220] A Dynam­i­cal Sys­tems Approach for Sta­tic Eval­u­a­tion in Go

    “In the paper argu­ments are given why the con­cept of sta­tic eval­u­a­tion has the poten­tial to be a use­ful exten­sion to Monte Carlo tree search. A new con­cept of mod­el­ing sta­tic eval­u­a­tion through a dynam­i­cal sys­tem is intro­duced and strengths and weak­nesses are dis­cussed. The gen­eral suit­abil­ity of this approach is demonstrated.”

    representation-​​theory plan­ning monte-​​carlo-​​models nudge algo­rithms
  • [1105.5449] AntNet: Dis­trib­uted Stig­mer­getic Con­trol for Com­mu­ni­ca­tions Networks

    “…We com­pare our algo­rithm with six state-​​of-​​the-​​art rout­ing algo­rithms com­ing from the telecom­mu­ni­ca­tions and machine learn­ing fields. The algo­rithms’ per­for­mance is eval­u­ated over a set of real­is­tic test­beds. We run many exper­i­ments over real and arti­fi­cial IP data­gram net­works with increas­ing num­ber of nodes and under sev­eral par­a­dig­matic spa­tial and tem­po­ral traf­fic dis­tri­b­u­tions. Results are very encour­ag­ing. AntNet showed supe­rior per­for­mance under all the exper­i­men­tal con­di­tions with respect to its com­peti­tors. We ana­lyze the main char­ac­ter­is­tics of the algo­rithm and try to explain the rea­sons for its superiority.”

    ant-​​colony-​​optimization network-​​theory net­works con­trol algo­rithms nudge-​​targets rout­ing
  • Bozo Sapi­ens: Sacco and Vanzetti: Evidence

    “Wigmore’s tech­nique, like prob­a­bil­ity itself, is both wide-​​ranging and tediously painstak­ing; his book was pop­u­lar only among insom­niac judges. But now that com­put­ers can take on the numer­i­cal drudgery, it is prov­ing its worth in just such tan­gled cases as Sacco’s and Vanzetti’s. The legal schol­ars Joseph Kadane and David Schum have applied a sophis­ti­cated exten­sion of Wigmore’s method to the vast body of evi­dence from the case. Theirs is a remark­able achieve­ment; their charts retain all the orig­i­nal com­plex­i­ties: the facts with­held or per­verted, the hearsay, the lies told and dis­avowed on both sides, the charged polit­i­cal atmos­phere of eighty years ago. They never dis­count a fact, no mat­ter how far-​​fetched; they  sim­ply give it its due weight in their dynamic struc­ture. Their con­clu­sion?  Unjust though it is to sum­ma­rize a book in a sen­tence, the bal­ance of prob­a­bil­ity seems to favor the view expressed long ago by one of the defen­dants’ close com­pan­ions: “every­one in the Boston anar­chis­tic cir­cle knew that Sacco was guilty and that Vanzetti was inno­cent as far as the actual par­tic­i­pa­tion in the killing.” So, there it is: whichever side our polit­i­cal instincts favor, we are des­tined to be half wrong. Vanzetti’s last words were: “I wish to for­give some peo­ple for what they are now doing to me.”  If we were all will­ing to make the extra effort to work out the prob­a­bil­i­ties, per­haps we might not need for­give­ness so often.”

    probability-​​theory legal-​​studies computational-​​methods his­tory
  • Get­ting first sale wrong

    “I hate to imag­ine it, but this deci­sion raises some fright­en­ing pos­si­bil­i­ties and requires greater vig­i­lance on the part of librar­i­ans.  At the very least, libraries must demand infor­ma­tion from pub­lish­ers about where every item has been man­u­fac­tured. Obtain­ing such infor­ma­tion is no longer an option, since our legal uses of the things we buy now depends on know­ing this, and the place where the pub­lisher is located or where the sale took place is sim­ply not suf­fi­cient.  But what I really fear is that pub­lish­ers will begin to man­u­fac­ture more of their works over­seas and then try to demand a higher price – one that includes “pub­lic lend­ing rights” – from libraries. If libraries are in a dif­fi­cult posi­tion, stu­dents may be even worse off under the Sec­ond Circuit’s rul­ing.  Again, pub­lish­ers now have an incen­tive to man­u­fac­ture their text­books abroad and sell them to U.S. stu­dents.  Such stu­dents would no longer have the right to re-​​sell their text­books or to pur­chase used texts.  The defen­dant in the case, Supap Kirt­saeng, had made a lucra­tive busi­ness out of reselling text­books pur­chased in Asia.  He was per­haps an unsym­pa­thetic party, but what he was doing was not dif­fer­ent in kind from the resale of texts that is com­mon on all col­lege cam­puses.  This activ­ity makes higher edu­ca­tion a lit­tle more pos­si­ble for many.  Now pub­lish­ers have an easy way for to close down this sec­ondary mar­ket for text­books, about which they have com­plained for years.  In the process, the cost of edu­ca­tion for col­lege stu­dents would be pushed up even further.”

    copy­right insan­ity intellectual-​​property academic-​​culture librar­i­ans
  • [1106.6037] Black Hole Search with Finite Automata Scat­tered in a Syn­chro­nous Torus

    “We con­sider the prob­lem of locat­ing a black hole in syn­chro­nous anony­mous net­works using finite state agents. A black hole is a harm­ful node in the net­work that destroys any agent vis­it­ing that node with­out leav­ing any trace. The objec­tive is to locate the black hole with­out destroy­ing too many agents. This is dif­fi­cult to achieve when the agents are ini­tially scat­tered in the net­work and are unaware of the loca­tion of each other. Pre­vi­ous stud­ies for black hole search used more pow­er­ful mod­els where the agents had non-​​constant mem­ory, were labelled with dis­tinct iden­ti­fiers and could either write mes­sages on the nodes of the net­work or mark the edges of the net­work. In con­trast, we solve the prob­lem using a small team of finite-​​state agents each car­ry­ing a con­stant num­ber of iden­ti­cal tokens that could be placed on the nodes of the net­work. Thus, all resources used in our algo­rithms are inde­pen­dent of the net­work size. We restrict our atten­tion to ori­ented torus net­works and first show that no finite team of finite state agents can solve the prob­lem in such net­works, when the tokens are not mov­able. In case the agents are equipped with mov­able tokens, we deter­mine lower bounds on the num­ber of agents and tokens required for solv­ing the prob­lem in torus net­works of arbi­trary size. Fur­ther, we present a deter­min­is­tic solu­tion to the black hole search prob­lem for ori­ented torus net­works, using the min­i­mum num­ber of agents and tokens.”

    algo­rithms agent-​​based multi-​​agent-​​systems network-​​theory nudge-​​targets
  • [1106.1821] Col­lec­tive Intel­li­gence, Data Rout­ing and Braess’ Paradox

    “We con­sider the prob­lem of design­ing the the util­ity func­tions of the utility-​​maximizing agents in a multi-​​agent sys­tem so that they work syn­er­gis­ti­cally to max­i­mize a global util­ity. The par­tic­u­lar prob­lem domain we explore is the con­trol of net­work rout­ing by plac­ing agents on all the routers in the net­work. Con­ven­tional approaches to this task have the agents all use the Ideal Short­est Path rout­ing Algo­rithm (ISPA). We demon­strate that in many cases, due to the side-​​effects of one agent’s actions on another agent’s per­for­mance, hav­ing agents use ISPA’s is sub­op­ti­mal as far as global aggre­gate cost is con­cerned, even when they are only used to route infin­i­tes­i­mally small amounts of traf­fic. The util­ity func­tions of the indi­vid­ual agents are not “aligned” with the global util­ity, intu­itively speak­ing. As a par­tic­u­lar exam­ple of this we present an instance of Braess’ para­dox in which adding new links to a net­work whose agents all use the ISPA results in a decrease in over­all through­put. We also demon­strate that load-​​balancing, in which the agents’ deci­sions are col­lec­tively made to opti­mize the global cost incurred by all traf­fic cur­rently being routed, is sub­op­ti­mal as far as global cost aver­aged across time is con­cerned. This is also due to ‘side-​​effects’, in this case of cur­rent rout­ing deci­sion on future traf­fic. The math­e­mat­ics of Col­lec­tive Intel­li­gence (COIN) is con­cerned pre­cisely with the issue of avoid­ing such dele­te­ri­ous side-​​effects in multi-​​agent sys­tems, both over time and space. We present key con­cepts from that math­e­mat­ics and use them to derive an algo­rithm whose ideal ver­sion should have bet­ter per­for­mance than that of hav­ing all agents use the ISPA, even in the infin­i­tes­i­mal limit. We present exper­i­ments ver­i­fy­ing this, and also show­ing that a machine-​​learning-​​based ver­sion of this COIN algo­rithm in which costs are only impre­cisely esti­mated via empir­i­cal means (a ver­sion poten­tially applic­a­ble in the real world) also out­per­forms the ISPA, despite hav­ing access to less infor­ma­tion than does the ISPA. In par­tic­u­lar, this COIN algo­rithm almost always avoids Braess’ paradox.”

    collective-​​intelligence search-​​algorithms figure-​​ground-​​error plan­ning nudge
  • [1108.0404] Exploit­ing Agent and Type Inde­pen­dence in Col­lab­o­ra­tive Graph­i­cal Bayesian Games

    “Effi­cient col­lab­o­ra­tive deci­sion mak­ing is an impor­tant chal­lenge for mul­ti­a­gent sys­tems. Find­ing opti­mal joint actions is espe­cially chal­leng­ing when each agent has only imper­fect infor­ma­tion about the state of its envi­ron­ment. Such prob­lems can be mod­eled as col­lab­o­ra­tive Bayesian games in which each agent receives pri­vate infor­ma­tion in the form of its type. How­ever, rep­re­sent­ing and solv­ing such games requires space and com­pu­ta­tion time expo­nen­tial in the num­ber of agents. This arti­cle intro­duces col­lab­o­ra­tive graph­i­cal Bayesian games (CGBGs), which facil­i­tate more effi­cient col­lab­o­ra­tive deci­sion mak­ing by decom­pos­ing the global pay­off func­tion as the sum of local pay­off func­tions that depend on only a few agents. We pro­pose a frame­work for the effi­cient solu­tion of CGBGs based on the insight that they posses two dif­fer­ent types of inde­pen­dence, which we call agent inde­pen­dence and type inde­pen­dence. In par­tic­u­lar, we present a fac­tor graph rep­re­sen­ta­tion that cap­tures both forms of inde­pen­dence and thus enables effi­cient solu­tions. In addi­tion, we show how this rep­re­sen­ta­tion can pro­vide lever­age in sequen­tial tasks by using it to con­struct a novel method for decen­tral­ized par­tially observ­able Markov deci­sion processes. Exper­i­men­tal results in both ran­dom and bench­mark tasks demon­strate the improved scal­a­bil­ity of our meth­ods com­pared to sev­eral exist­ing alternatives.”

    col­lab­o­ra­tion agent-​​based complex-​​systems emergent-​​design nudge-​​targets
  • [1102.2837] Effi­cient Pro­mo­tion Strate­gies in Hier­ar­chi­cal Organizations

    “The Peter prin­ci­ple has been recently inves­ti­gated by means of an agent-​​based sim­u­la­tion and its valid­ity has been numer­i­cally cor­rob­o­rated. It has been con­firmed that, within cer­tain con­di­tions, it can really influ­ence in a neg­a­tive way the effi­ciency of a pyra­mi­dal orga­ni­za­tion adopt­ing mer­i­to­cratic pro­mo­tions. It was also found that, in order to bypass these effects, alter­na­tive pro­mo­tion strate­gies should be adopted, as for exam­ple a ran­dom selec­tion choice. In this paper, within the same line of research, we study pro­mo­tion strate­gies in a more real­is­tic hier­ar­chi­cal and mod­u­lar orga­ni­za­tion and we show the robust­ness of our pre­vi­ous results, extend­ing their valid­ity to a more gen­eral con­text. We dis­cuss also why the adop­tion of these strate­gies could be use­ful for real organizations.”

    organizational-​​behavior com­plex­ol­ogy complexological-​​amusements agent-​​based com­pe­tence

Items of some interest…

These are my recent Pin​board​.in links:

  • [1101.4003] Dyna-​​H: a heuris­tic plan­ning rein­force­ment learn­ing algo­rithm applied to role-​​playing-​​game strat­egy deci­sion systems

    “In a Role-​​Playing Game, find­ing opti­mal tra­jec­to­ries is one of the most impor­tant tasks. In fact, the strat­egy deci­sion sys­tem becomes a key com­po­nent of a game engine. Deter­min­ing the way in which deci­sions are taken (online, batch or sim­u­lated) and the con­sumed resources in deci­sion mak­ing (e.g. exe­cu­tion time, mem­ory) will influ­ence, in mayor degree, the game per­for­mance. When clas­si­cal search algo­rithms such as A* can be used, they are the very first option. Nev­er­the­less, such meth­ods rely on pre­cise and com­plete mod­els of the search space, and there are many inter­est­ing sce­nar­ios where their appli­ca­tion is not pos­si­ble. Then, model free meth­ods for sequen­tial deci­sion mak­ing under uncer­tainty are the best choice. In this paper, we pro­pose a heuris­tic plan­ning strat­egy to incor­po­rate the abil­ity of heuristic-​​search in path-​​finding into a Dyna agent. The pro­posed Dyna-​​H algo­rithm, as A* does, selects branches more likely to pro­duce out­comes than other branches. Besides, it has the advan­tages of being a model-​​free online rein­force­ment learn­ing algo­rithm. The pro­posal was eval­u­ated against the one-​​step Q-​​Learning and Dyna-​​Q algo­rithms obtain­ing excel­lent exper­i­men­tal results: Dyna-​​H sig­nif­i­cantly over­comes both meth­ods in all exper­i­ments. We sug­gest also, a func­tional anal­ogy between the pro­posed sam­pling from worst tra­jec­to­ries heuris­tic and the role of dreams (e.g. night­mares) in human behavior.”

    plan­ning machine-​​learning nudge-​​targets easy-​​pickins
  • [0908.3565] Dis­trib­uted Loca­tion Opti­miza­tion for Sen­sors with Lim­ited Range Het­ero­ge­neous Capa­bil­i­ties using Gen­er­al­ized Voronoi Partition

    “In this paper a gen­er­al­iza­tion of the Voronoi par­ti­tion is used for solv­ing a het­ero­ge­neous dis­trib­uted loca­tional opti­miza­tion prob­lem for autonomous agents, such as AGVs, UAVs, etc. The prob­lem addressed is of opti­mal deploy­ment of agents equipped with sen­sors, hav­ing het­ero­ge­neous capa­bil­i­ties, and lim­ited range, to max­i­mize sen­sor cov­er­age. An objec­tive func­tion for opti­mal deploy­ment of agents is for­mu­lated, and its crit­i­cal points are deter­mined. The opti­mal deploy­ment is shown to be the gen­er­al­ized cen­troidal Voronoi con­fig­u­ra­tion in which the agents are located at the cen­troids of the cor­re­spond­ing gen­er­al­ized Voronoi cells. For­mal results on sta­bil­ity, con­ver­gence, and on spa­tial dis­tri­b­u­tion of the pro­posed con­trol laws respon­si­ble for agent motion, under some con­straints on the agents’ speeds and limit on sen­sor range are pro­vided. The the­o­ret­i­cal results are sup­ported with illus­tra­tive simulation”

    agent-​​based coor­di­na­tion sensor-​​networks nudge-​​targets emergent-​​design
  • [1106.6058] Sta­bil­ity of strate­gies in payoff-​​driven evo­lu­tion­ary games on networks

    “We con­sider a net­work of cou­pled agents play­ing the Prisoner’s Dilemma game, in which play­ers are allowed to pick a strat­egy in the inter­val [0,1], with 0 cor­re­spond­ing to defec­tion, 1 to coop­er­a­tion, and inter­me­di­ate val­ues rep­re­sent­ing mixed strate­gies in which each player may act as a coop­er­a­tor or a defec­tor over a large num­ber of inter­ac­tions with a cer­tain prob­a­bil­ity. Our model is payoff-​​driven, i.e., we assume that the level of accu­mu­lated pay­off at each node is a rel­e­vant para­me­ter in the selec­tion of strate­gies. Also, we con­sider that each player chooses his/​her strat­egy in a con­text of lim­ited infor­ma­tion. We present a deter­min­is­tic non­lin­ear model for the evo­lu­tion of strate­gies. We show that the final strate­gies depend on the net­work struc­ture and on the choice of the para­me­ters of the game. We find that polar­ized strate­gies (pure cooperator/​defector states) typ­i­cally emerge when (i) the net­work con­nec­tions are sparse, (ii) the net­work degree dis­tri­b­u­tion is het­ero­ge­neous, (iii) the net­work is assor­ta­tive, and sur­pris­ingly, (iv) the ben­e­fit of coop­er­a­tion is high.”

    prisoners’-dilemma agent-​​based network-​​theory artificial-​​life com­plex­ol­ogy nudge-​​targets
  • [1106.0296] The Emer­gence of Lead­er­ship in Social Networks

    “We study a net­worked ver­sion of the minor­ity game in which agents can choose to fol­low the choices made by a neigh­bour­ing agent in a social net­work. We show that for a wide vari­ety of net­works a lead­er­ship struc­ture always emerges, with most agents fol­low­ing the choice made by a few agents. We find a suit­able para­me­ter­i­sa­tion which high­lights the uni­ver­sal aspects of the behav­iour and which also indi­cates where results depend on the type of social network.”

    minority-​​game social-​​networks soci­ol­ogy agent-​​based network-​​theory
  • [1106.1816] Mon­i­tor­ing Teams by Over­hear­ing: A Multi-​​Agent Plan-​​Recognition Approach

    “Recent years are see­ing an increas­ing need for on-​​line mon­i­tor­ing of teams of coop­er­at­ing agents, e.g., for visu­al­iza­tion, or per­for­mance track­ing. How­ever, in mon­i­tor­ing deployed teams, we often can­not rely on the agents to always com­mu­ni­cate their state to the mon­i­tor­ing sys­tem. This paper presents a non-​​intrusive approach to mon­i­tor­ing by ‘over­hear­ing’, where the mon­i­tored team’s state is inferred (via plan-​​recognition) from team-​​members’ rou­tine com­mu­ni­ca­tions, exchanged as part of their coor­di­nated task exe­cu­tion, and observed (over­heard) by the mon­i­tor­ing sys­tem. Key chal­lenges in this approach include the demand­ing run-​​time require­ments of mon­i­tor­ing, the scarce­ness of obser­va­tions (increas­ing mon­i­tor­ing uncer­tainty), and the need to scale-​​up mon­i­tor­ing to address poten­tially large teams. To address these, we present a set of com­ple­men­tary novel tech­niques, exploit­ing knowl­edge of the social struc­tures and pro­ce­dures in the mon­i­tored team: (i) an effi­cient prob­a­bilis­tic plan-​​recognition algo­rithm, well-​​suited for pro­cess­ing com­mu­ni­ca­tions as obser­va­tions; (ii) an approach to exploit­ing knowl­edge of the team’s social behav­ior to pre­dict future obser­va­tions dur­ing exe­cu­tion (reduc­ing mon­i­tor­ing uncer­tainty); and (iii) mon­i­tor­ing algo­rithms that trade expres­siv­ity for scal­a­bil­ity, rep­re­sent­ing only cer­tain use­ful mon­i­tor­ing hypothe­ses, but allow­ing for any num­ber of agents and their dif­fer­ent activ­i­ties to be rep­re­sented in a sin­gle coher­ent entity. We present an empir­i­cal eval­u­a­tion of these tech­niques, in com­bi­na­tion and apart, in mon­i­tor­ing a deployed team of agents, run­ning on machines phys­i­cally dis­trib­uted across the coun­try, and engaged in com­plex, dynamic task exe­cu­tion. We also com­pare the per­for­mance of these tech­niques to human expert and novice mon­i­tors, and show that the tech­niques pre­sented are capa­ble of mon­i­tor­ing at human-​​expert lev­els, despite the dif­fi­culty of the task.”

    emergent-​​design agent-​​based swarms coor­di­na­tion nudge
  • [1011.2861] A Com­pre­hen­sive Work­flow for General-​​Purpose Neural Mod­el­ing with Highly Con­fig­urable Neu­ro­mor­phic Hard­ware Systems

    “In this paper we present a method­olog­i­cal frame­work that meets novel require­ments emerg­ing from upcom­ing types of accel­er­ated and highly con­fig­urable neu­ro­mor­phic hard­ware sys­tems. We describe in detail a device with 45 mil­lion pro­gram­ma­ble and dynamic synapses that is cur­rently under devel­op­ment, and we sketch the con­cep­tual chal­lenges that arise from tak­ing this plat­form into oper­a­tion. More specif­i­cally, we aim at the estab­lish­ment of this neu­ro­mor­phic sys­tem as a flex­i­ble and neu­ro­sci­en­tif­i­cally valu­able mod­el­ing tool that can be used by non-​​hardware-​​experts. We con­sider var­i­ous func­tional aspects to be cru­cial for this pur­pose, and we intro­duce a con­sis­tent work­flow with detailed descrip­tions of all involved mod­ules that imple­ment the sug­gested steps: The inte­gra­tion of the hard­ware inter­face into the simulator-​​independent model descrip­tion lan­guage PyNN; a fully auto­mated trans­la­tion between the PyNN domain and appro­pri­ate hard­ware con­fig­u­ra­tions; an exe­cutable spec­i­fi­ca­tion of the future neu­ro­mor­phic sys­tem that can be seam­lessly inte­grated into this biology-​​to-​​hardware map­ping process as a test bench for all soft­ware lay­ers and pos­si­ble hard­ware design mod­i­fi­ca­tions; an eval­u­a­tion scheme that deploys mod­els from a ded­i­cated bench­mark library, com­pares the results gen­er­ated by vir­tual or pro­to­type hard­ware devices with ref­er­ence soft­ware sim­u­la­tions and ana­lyzes the dif­fer­ences. The inte­gra­tion of these com­po­nents into one hardware-​​software work­flow pro­vides an ecosys­tem for ongo­ing prepar­a­tive stud­ies that sup­port the hard­ware design process and rep­re­sents the basis for the matu­rity of the model-​​to-​​hardware map­ping soft­ware. The func­tion­al­ity and flex­i­bil­ity of the lat­ter is proven with a vari­ety of exper­i­men­tal results.”

    neural-​​networks biologically-​​inspired elec­tron­ics emergent-​​design nudge-​​targets

Items of some interest…

These are my recent Pin​board​.in links:

  • [1106.4577] Inter­ac­tive Exe­cu­tion Mon­i­tor­ing of Agent Teams

    “There is an increas­ing need for auto­mated sup­port for humans mon­i­tor­ing the activ­ity of dis­trib­uted teams of coop­er­at­ing agents, both human and machine. We char­ac­ter­ize the domain-​​independent chal­lenges posed by this prob­lem, and describe how prop­er­ties of domains influ­ence the chal­lenges and their solu­tions. We will con­cen­trate on dynamic, data-​​rich domains where humans are ulti­mately respon­si­ble for team behav­ior. Thus, the auto­mated aid should inter­ac­tively sup­port effec­tive and timely deci­sion mak­ing by the human. We present a domain-​​independent cat­e­go­riza­tion of the types of alerts a plan-​​based mon­i­tor­ing sys­tem might issue to a user, where each type gen­er­ally requires dif­fer­ent mon­i­tor­ing tech­niques. We describe a mon­i­tor­ing frame­work for inte­grat­ing many domain-​​specific and task-​​specific mon­i­tor­ing tech­niques and then using the con­cept of value of an alert to avoid oper­a­tor over­load. We use this frame­work to describe an exe­cu­tion mon­i­tor­ing approach we have used to imple­ment Exe­cu­tion Assis­tants (EAs) in two dif­fer­ent dynamic, data-​​rich, real-​​world domains to assist a human in mon­i­tor­ing team behav­ior. One domain (Army small unit oper­a­tions) has hun­dreds of mobile, geo­graph­i­cally dis­trib­uted agents, a com­bi­na­tion of humans, robots, and vehi­cles. The other domain (teams of unmanned ground and air vehi­cles) has a hand­ful of coop­er­at­ing robots. Both domains involve unpre­dictable adver­saries in the vicin­ity. Our approach cus­tomizes mon­i­tor­ing behav­ior for each spe­cific task, plan, and sit­u­a­tion, as well as for user pref­er­ences. Our EAs alert the human con­troller when reported events threaten plan exe­cu­tion or phys­i­cally threaten team mem­bers. Alerts were gen­er­ated in a timely man­ner with­out inun­dat­ing the user with too many alerts (less than 10 per­cent of alerts are unwanted, as judged by domain experts).”

    emergent-​​design multi-​​agent-​​systems engineering-​​design con­trol coor­di­na­tion nudge-​​targets
  • [1107.1322] Text Clas­si­fi­ca­tion: A Sequen­tial Read­ing Approach

    “We pro­pose to model the text clas­si­fi­ca­tion process as a sequen­tial deci­sion process. In this process, an agent learns to clas­sify doc­u­ments into top­ics while read­ing the doc­u­ment sen­tences sequen­tially and learns to stop as soon as enough infor­ma­tion was read for decid­ing. The pro­posed algo­rithm is based on a mod­eli­sa­tion of Text Clas­si­fi­ca­tion as a Markov Deci­sion Process and learns by using Rein­force­ment Learn­ing. Exper­i­ments on four dif­fer­ent clas­si­cal mono-​​label cor­pora show that the pro­posed approach per­forms com­pa­ra­bly to clas­si­cal SVM approaches for large train­ing sets, and bet­ter for small train­ing sets. In addi­tion, the model auto­mat­i­cally adapts its read­ing process to the quan­tity of train­ing infor­ma­tion provided.”

    text-​​classification natural-​​language-​​processing machine-​​learning nudge-​​targets
  • [1011.0362] Opti­miza­tion of arti­fi­cial flock­ings by means of anisotropy measurements

    “An effec­tive pro­ce­dure to deter­mine the opti­mal para­me­ters appear­ing in arti­fi­cial flock­ings is pro­posed in terms of opti­miza­tion prob­lems. We numer­i­cally exam­ine genetic algo­rithms (GAs) to deter­mine the opti­mal set of para­me­ters such as the weights for three essen­tial inter­ac­tions in BOIDS by Reynolds (1987) under ‘zero-​​collision’ and ‘no-​​breaking-​​up’ con­straints. As a fit­ness func­tion (the energy func­tion) to be max­i­mized by the GA, we choose the so-​​called the $gamma$-value of anisotropy which can be observed empir­i­cally in typ­i­cal flocks of star­ling. We con­firm that the GA suc­cess­fully finds the solu­tion hav­ing a large $gamma$-value leading-​​up to a strong anisotropy. The numer­i­cal expe­ri­ence shows that the pro­ce­dure might enable us to make more real­is­tic and effi­cient arti­fi­cial flock­ing of star­ling even in our per­sonal com­put­ers. We also eval­u­ate two dis­tinct types of inter­ac­tions in agents, namely, met­ric and topo­log­i­cal def­i­n­i­tions of inter­ac­tions. We con­firmed that the topo­log­i­cal def­i­n­i­tion can explain the empir­i­cal evi­dence much bet­ter than the met­ric def­i­n­i­tion does.”

    artificial-​​life network-​​theory sim­u­la­tion boids opti­miza­tion nudge-​​targets
  • [1106.5316] Online Cake Cut­ting (pub­lished version)

    “We pro­pose an online form of the cake cut­ting prob­lem. This mod­els sit­u­a­tions where agents arrive and depart dur­ing the process of divid­ing a resource. We show that well known fair divi­sion pro­ce­dures like cut-​​and-​​choose and the Dubins-​​Spanier mov­ing knife pro­ce­dure can be adapted to apply to such online prob­lems. We pro­pose some fair­ness prop­er­ties that online cake cut­ting pro­ce­dures can pos­sess like online forms of pro­por­tion­al­ity and envy-​​freeness. We also con­sider the impact of col­lu­sion between agents. Finally, we study the­o­ret­i­cally and empir­i­cally the com­pet­i­tive ratio of these online cake cut­ting pro­ce­dures. Based on its resis­tance to col­lu­sion, and its good per­for­mance in prac­tice, our results favour the online ver­sion of the cut-​​and-​​choose pro­ce­dure over the online ver­sion of the mov­ing knife procedure.”

    game-​​theory economic-​​crisis decision-​​making fair­ness nudge-​​targets