Iskanje po katalogu digitalne knjižnice

Iskalni niz:	išči po
	išči po
	išči po
	išči po
Vrsta gradiva:	* po starem in bolonjskem študiju
Jezik:
Išči po:
Opcije:	Prikaži samo zadetke s celotnim besedilom
	Ponastavi

1 - 2 / 2

Languages cool as they expand: allometric scaling and the decreasing need for new words
Alexander Petersen, Joel Tenenbaum, Shlomo Havlin, Harry Eugene Stanley, Matjaž Perc, 2012, izvirni znanstveni članek

Opis: We analyze the occurrence frequencies of over 15 million words recorded in millions of books published during the past two centuries in seven different languages. For all languages and chronological subsets of the data we confirm that two scaling regimes characterize the word frequency distributions, with only the more common words obeying the classic Zipf law. Using corpora of unprecedented size, we test the allometric scaling relation between the corpus size and the vocabulary size of growing languages to demonstrate a decreasing marginal need for new words, a feature that is likely related to the underlying correlations between words. We calculate the annual growth fluctuations of word use which has a decreasing trend as the corpus size increases, indicating a slowdown in linguistic evolution following language expansion. This cooling pattern forms the basis of a third statistical regularity, which unlike the Zipf and the Heaps law, is dynamical in nature.
Ključne besede: culturomics, society, culture, quantitative linguistics, physics of social systems
Objavljeno v DKUM: 23.06.2017; Ogledov: 953; Prenosov: 373
Celotno besedilo (2,03 MB)
Gradivo ima več datotek! Več...

Heterogeneous aspirations promote cooperation in the prisoner's dilemma game
Matjaž Perc, Zhen Wang, 2010, izvirni znanstveni članek

Opis: To be the fittest is central to proliferation in evolutionary games. Individuals thus adopt the strategies of better performing players in the hopeof successful reproduction. In structured populations the array of those that are eligible to act as strategy sources is bounded to the immediate neighbors of each individual. But which one of these strategy sources should potentially be copied? Previous research dealt with this question either by selecting the fittest or by selecting one player uniformly at random. Here we introduce a parameter that interpolates between these two extreme options. Setting equal to zero returns the random selection of the opponent, while positive favor the fitter players. In addition, we divide the population intotwo groups. Players from group select their opponents as dictated by the parameter , while players from group do so randomly irrespective of . We denote the fraction of players contained in groups and by and , respectively. The two parameters and allow us to analyze in detail how aspirations in the context of the prisoner's dilemma game influence the evolution of cooperation. We find that for sufficiently positive values of there exist a robust intermediate for which cooperation thrives best. The robustness of this observation is tested against different levels of uncertainty in the strategy adoption process and for different interaction networks. We also provide complete phase diagrams depicting the dependence of the impact of and for different values of , and contrast the validity of ourconclusions by means of an alternative model where individual aspiration levels are subject to evolution as well. Our study indicates that heterogeneity in aspirations may be key for the sustainability of cooperation in structured populations.
Ključne besede: evolutionary game theory, prisoner's dilemma, spatial games, aspirations, social systems, physics and society
Objavljeno v DKUM: 19.06.2017; Ogledov: 1476; Prenosov: 386
Celotno besedilo (822,95 KB)
Gradivo ima več datotek! Več...

Iskanje izvedeno v 0.07 sek.

Na vrh