Network Selection and Resource Allocation Games for Wireless Access Networks

Wireless access networks are often characterized by the interaction of different end users, communication technologies, and network operators. This paper analyzes the dynamics among these "actors" by focusing on the processes of wireless network selection, where end users may choose among multiple available access networks to get connectivity, and resource allocation, where network operators may set their radio resources to provide connectivity. The interaction among end users is modeled as a non-cooperative congestion game where players (end users) selfishly select the access network that minimizes their perceived selection cost. A method based on mathematical programming is proposed to find Nash equilibria and characterize their optimality under three cost functions, which are representative of different technological scenarios. System level simulations are then used to evaluate the actual throughput and fairness of the equilibrium points. The interaction among end users and network operators is then assessed through a two-stage multi-leader/multi-follower game, where network operators (leaders) play in the first stage by properly setting the radio resources to maximize their users, and end users (followers) play in the second stage the aforementioned network selection game. The existence of exact and approximated subgame perfect Nash equilibria of the two-stage game is thoroughly assessed and numerical results are provided on the "quality" of such equilibria

Stochastic characterization of the spectrum sharing game in ad-hoc networks

Abstract This work focuses on infrastructure-less ad hoc wireless networks where multiple transmitter/receiver pairs share the same radio resources (spectrum); transmitters have to choose how to split a total power budget across orthogonal spectrum bands with the goal to maximize their sum rate under cumulative interference from concurrent transmissions. We start off by introducing and characterizing the non-cooperative game among transmitter/receiver pairs when the network topology is deterministically given. The corresponding Nash equilibria are derived, highlighting their dependency on the topological parameters (distances between wireless nodes, propagation model, and background noise power). The analysis is then extended to the case of random network topologies drawn from a given spatial stochastic process. Tools of stochastic geometry are leveraged to derive a statistical characterization of the equilibria of the spectrum sharing game. Finally, a distributed algorithm is proposed to let the players of the spectrum sharing game converge to equilibria conditions. Numerical simulations show that the proposed algorithm drives the users to stable points that are close to the equilibria of the game requiring limited information exchange among nodes

Dynamic Pricing for Tenants in an Automated Slicing Marketplace

The paradigm shift from a one-size-fits-all architecture to a service-oriented network infrastructure promised by network slicing will demand novel technical solutions, as well as new business models. In particular, the role separation between infrastructure providers, i.e. the ones owning the network, and slice tenants, i.e. the ones providing specialized services tailored to their vertical segments, may encourage the definition of a shared platform (or marketplace) where the former can monetize their network infrastructure by leasing network resources at a market price, and the latter can rent on-demand the network resources needed to offer their services at the desired quality. This also enables the flexibility for the slice tenants to optimize the management of their slices by adapting their resource demand to fluctuations of their traffic or variations of the price in the market. In this paper, we extend the market mechanism scheme developed in previous works by including intra-slice radio admission control policies in the utility definition of the tenants in the slicing market game. Moreover, we characterize the mathematical properties of the game with respect to slice configuration, i.e. how diverse strategical behavior of the tenants affects the market operation, in terms of slice resource allocation and performance. Our analysis offers insights to the slice tenants on how they could reconfigure their techno-economic performance indicators in response to the dynamics of network and of the market, namely how to adapt their long-term (and/or real-time) strategies to the fluctuations of the traffic to enhance network performance and increase profits

Assessing Creative Expressiveness In Children's Written Stories Using The Consensual Assessment Technique

The study investigated methodological issues relating to the use of the Consensual Assessment Technique (CAT) for measuring creativity in children’s written stories. The CAT is a commonly used measure to estimate creativity of a product, based on social recognition of creativity by independent judges. Across domains, the CAT has shown high inter-rater reliability. The present study utilised the CAT to assess creativity in children’s written stories. The stories were also evaluated for: Imagination, Novelty, Liking (how much the judges liked the story), Detail, Emotion, Vocabulary, Straightforwardness, Logic and Grammar. The sample consisted of 277 nine-year-olds. The results showed that to reach sufficient inter-rater reliability, 5 coders were needed. The results gave evidence of a 2-factor structure among the 10 dimensions, indexing ‘Creative Expressiveness’ and ‘Logic’ constructs related to individual differences in writing. Girls outperformed boys on both constructs. The story length was positively correlated with the constructs, explaining 63% of the variance in Creative Expressiveness, and 42% in Logic. Creative Expressiveness was positively correlated with verbal ability (r = .20) and with teacher rating of writing (r = .28). Similarly, Logic was also correlated with verbal ability (r = .34) and teacher rating of writing (r = .44). The findings inform future research employing the CAT to measure creativity in children’s storytelling

Reading Self-Perceived Ability, Enjoyment and Achievement: A Genetically Informative Study of Their Reciprocal Links Over Time

Extant literature has established a consistent association between aspects of reading motivation, such as enjoyment and self-perceived ability, and reading achievement, in that more motivated readers are generally more skilled readers. However, the developmental etiology of this relation is yet to be investigated. The present study explores the development of the motivation–achievement association and its genetic and environmental underpinnings. Applying cross-lagged design in a sample of 13,825 twins, we examined the relative contribution of genetic and environmental factors to the association between reading enjoyment and self-perceived ability and reading achievement. Children completed a reading comprehension task and self-reported their reading enjoyment and perceived ability twice in middle childhood: when they were 9 –10 and 12 years old. Results showed a modest reciprocal association over time between reading motivation (enjoyment and perceived ability) and reading achievement. Reading motivation at age 9 –10 statistically predicted the development of later achievement, and similarly, reading achievement at age 9 –10 predicted the development of later motivation. This reciprocal association was observed beyond the stability of the variables and their contemporaneous correlation and was largely explained by genetic factors

Assessing Creative Expressiveness in Children’s Written Stories Using the Consensual Assessment Technique

The study investigated methodological issues relating to the use of the Consensual Assessment Technique (CAT) for measuring creativity in children’s written stories. The CAT is a commonly used measure to estimate creativity of a product, based on social recognition of creativity by independent judges. Across domains, the CAT has shown high inter-rater reliability. The present study utilised the CAT to assess creativity in children’s written stories. The stories were also evaluated for: Imagination, Novelty, Liking (how much the judges liked the story), Detail, Emotion, Vocabulary, Straightforwardness, Logic and Grammar. The sample consisted of 277 nine-year-olds. The results showed that to reach sufficient inter-rater reliability, 5 coders were needed. The results gave evidence of a 2-factor structure among the 10 dimensions, indexing ‘Creative Expressiveness’ and ‘Logic’ constructs related to individual differences in writing. Girls outperformed boys on both constructs. The story length was positively correlated with the constructs, explaining 63% of the variance in Creative Expressiveness, and 42% in Logic. Creative Expressiveness was positively correlated with verbal ability (r = .20) and with teacher rating of writing (r = .28). Similarly, Logic was also correlated with verbal ability (r = .34) and teacher rating of writing (r = .44). The findings inform future research employing the CAT to measure creativity in children’s storytelling

Aggressive behaviour in childhood and adolescence : the role of smoking during pregnancy, evidence from four twin cohorts in the EU-ACTION consortium

Background Maternal smoking during pregnancy (MSDP) has been linked to offspring's externalizing problems. It has been argued that socio-demographic factors (e.g. maternal age and education), co-occurring environmental risk factors, or pleiotropic genetic effects may account for the association between MSDP and later outcomes. This study provides a comprehensive investigation of the association between MSDP and a single harmonized component of externalizing: aggressive behaviour, measured throughout childhood and adolescence. Methods Data came from four prospective twin cohorts - Twins Early Development Study, Netherlands Twin Register, Childhood and Adolescent Twin Study of Sweden, and FinnTwin12 study - who collaborate in the EU-ACTION consortium. Data from 30 708 unrelated individuals were analysed. Based on item level data, a harmonized measure of aggression was created at ages 9-10; 12; 14-15 and 16-18. Results MSDP predicted aggression in childhood and adolescence. A meta-analysis across the four samples found the independent effect of MSDP to be 0.4% (r = 0.066), this remained consistent when analyses were performed separately by sex. All other perinatal factors combined explained 1.1% of the variance in aggression across all ages and samples (r = 0.112). Paternal smoking and aggressive parenting strategies did not account for the MSDP-aggression association, consistent with the hypothesis of a small direct link between MSDP and aggression. Conclusions Perinatal factors, including MSDP, account for a small portion of the variance in aggression in childhood and adolescence. Later experiences may play a greater role in shaping adolescents' aggressive behaviour.Peer reviewe

Investigating the genetic architecture of noncognitive skills using GWAS-by-subtraction

Little is known about the genetic architecture of traits affecting educational attainment other than cognitive ability. We used genomic structural equation modeling and prior genome-wide association studies (GWASs) of educational attainment (n = 1,131,881) and cognitive test performance (n = 257,841) to estimate SNP associations with educational attainment variation that is independent of cognitive ability. We identified 157 genome-wide-significant loci and a polygenic architecture accounting for 57% of genetic variance in educational attainment. Noncognitive genetics were enriched in the same brain tissues and cell types as cognitive performance, but showed different associations with gray-matter brain volumes. Noncognitive genetics were further distinguished by associations with personality traits, less risky behavior and increased risk for certain psychiatric disorders. For socioeconomic success and longevity, noncognitive and cognitive-performance genetics demonstrated associations of similar magnitude. By conducting a GWAS of a phenotype that was not directly measured, we offer a view of genetic architecture of noncognitive skills influencing educational success

Investigating the genetic architecture of noncognitive skills using GWAS-by-subtraction

Little is known about the genetic architecture of traits affecting educational attainment other than cognitive ability. We used genomic structural equation modeling and prior genome-wide association studies (GWASs) of educational attainment (n = 1,131,881) and cognitive test performance (n = 257,841) to estimate SNP associations with educational attainment variation that is independent of cognitive ability. We identified 157 genome-wide-significant loci and a polygenic architecture accounting for 57% of genetic variance in educational attainment. Noncognitive genetics were enriched in the same brain tissues and cell types as cognitive performance, but showed different associations with gray-matter brain volumes. Noncognitive genetics were further distinguished by associations with personality traits, less risky behavior and increased risk for certain psychiatric disorders. For socioeconomic success and longevity, noncognitive and cognitive-performance genetics demonstrated associations of similar magnitude. By conducting a GWAS of a phenotype that was not directly measured, we offer a view of genetic architecture of noncognitive skills influencing educational success