A social network often has numerous interesting attributes. When an attribute is quantified, a social tomography would arise from the underlying social network. One of the most interesting attributes is crime hotspots, whose existence has been strongly supported by observations that serious crimes ranging from residential burglary to homicide are strongly patterned in time and space, and by mathematical modeling. So far, however, the structures of hotspots, including their size distributions, have not been adequately studied. Here, we focus on a special type of hotspots, the sex offender clusters, in the United States, and show that their size distribution, where size is defined as the ratio between sex offender population and total population in a 5-digit zip code area, follows a power-law distribution. In contrast, such local total population, both general and sex offenders, do not quite follow power-laws. A heavy-tailed power-law distribution is fundamentally different from a thin-tailed distribution such as a Poisson distribution, and can be used as an objective criterion for defining sex offender clusters. More fundamentally, a power-law is a defining property of self-similarity or fractal behavior. Therefore, our finding indicates that sex offender clusters, size-wise, self-organize into a fractal, due to interplay of economic conditions of offenders, policies and public perceptions.

Patterns of animate and inanimate systems show remarkable similarities in their aggregation. One similarity is the double-Pareto distribution of the aggregate-size of system components. Different models have been developed to predict aggregates of system components. However, not many models have been developed to describe probabilistically the aggregate-size distribution of any system regardless of the intrinsic and extrinsic drivers of the aggregation process. Here we consider natural animate systems, from one of the greatest mammals - the African elephant (Loxodonta africana) - to the Escherichia coli bacteria, and natural inanimate systems in river basins. Considering aggregates as islands and their perimeter as a curve mirroring the sculpting network of the system, the probability of exceedence of the drainage area, and the Hack’s law are shown to be the the Korˇcak’s law and the perimeter-area relationship for river basins. The perimeter-area relationship, and the probability of exceedence of the aggregate-size provide a meaningful estimate of the same fractal dimension. Systems aggregate because of the influence exerted by a physical or processes network within the system domain. The aggregate-size distribution is accurately derived using the null-method of box-counting on the occurrences of system components. The importance of the aggregate-size spectrum relies on its ability to reveal system form, function, and dynamics also as a function of other coupled systems. Variations of the fractal dimension and of the aggregate-size distribution are related to changes of systems that are meaningful to monitor because potentially critical for these systems.

An introduction to the key topics in the cognitive science of cyber defence analysis including an overview of the challenges that exist and need to be faced in the field.

The advent of technologies that can seamlessly operate in different environments with differing levels of security present new challenges to the cybersecurity specialist seeking to ensure the safety of data, process or output of a complex system. This paper reviews the human dimension of cybersecurity. The Human Factors Integration (HFI) framework is employed as a structure with which to consider the many ways in which the human can differentially affect the security of a system both positively and negatively. We conclude that when the human factors element is analysed when specifying and designing secure and safe systems, it is far more likely that the human can assist and increase the overall level of security. As in other high technology sectors such as aviation or petrochemical, if not considered, the human can often ‘bulldoze’ through the most carefully considered and designed security or safety barriers

Future conflicts will necessitate the ability to conduct effective military operations in a contested information environment. The building and maintaining of robust situational awareness, protection of decision-making effectiveness of individuals and teams, fighting through information attacks from both in, and through, the cyberspace domain, will be essential. Increasing the knowledge of the mechanisms involved in degrading task performance and decision-making during cyber attacks will enable the development of advanced human-centered defensive techniques that aid fight-through capability. In this position paper, the development and evaluation of software that simulates real-time and persistent manipulation of the information environment is discussed. Results of the evaluation indicated that the task performance of a team of decision-makers performing collaborative tasks could be degraded through real-time manipulation of cyberspace content and operation. The paper concludes with a discussion of focus and direction for future research and development. It is suggested that the building of a deeper understanding of the perceptual and cognitive factors that are significant in the relationship between information environment manipulation and reduction in task performance is required. This understanding will aid in the defence of cyberspace attacks, will aid in fight through and mission assurance, and will aid the Information Operations community.