Booting the booters: Evaluating the effects of police interventions in the market for Denial-of-Service attacks

Illegal booter services offer denial of service (DoS) attacks for a fee of a few tens of dollars a month. Internationally, police have implemented a range of different types of intervention aimed at those using and offering booter services, including arrests and website takedown. In order to measure the impact of these interventions we look at the usage reports that booters themselves provide and at measurements of reflected UDP DoS attacks, leveraging a five year measurement dataset that has been statistically demonstrated to have very high coverage. We analysed time series data (using a negative binomial regression model) to show that several interventions have had a statistically significant impact on the number of attacks. We show that, while there is no consistent effect of highly-publicised court cases, takedowns of individual booters precede significant, but short-lived, reductions in recorded attack numbers. However, more wide-ranging disruptions have much longer effects. The closure of HackForums' booter market reduced attacks for 13 weeks globally (and for longer in particular countries) and the FBI's coordinated operation in December 2018, which involved both takedowns and arrests, reduced attacks by a third for at least 10 weeks and resulted in lasting change to the structure of the booter market.This work was supported by the Engineering and Physical Sciences Research Council (EPSRC) [grant number EP/M020320/1]

Characterization of space dust using acoustic impact detection

This paper describes studies leading to the development of an acoustic instrument for measuring properties of micrometeoroids and other dust particles in space. The instrument uses a pair of easily penetrated membranes separated by a known distance. Sensors located on these films detect the transient acoustic signals produced by particle impacts. The arrival times of these signals at the sensor locations are used in a simple multilateration calculation to measure the impact coordinates on each film. Particle direction and speed are found using these impact coordinates and the known membrane separations. This ability to determine particle speed, direction, and time of impact provides the information needed to assign the particle’s orbit and identify its likely origin. In many cases additional particle properties can be estimated from the signal amplitudes, including approximate diameter and (for small particles) some indication of composition/morphology. Two versions of this instrument were evaluated in this study. Fiber optic displacement sensors are found advantageous when very thin membranes can be maintained in tension (solar sails, lunar surface). Piezoelectric strain sensors are preferred for thicker films without tension (long duration free flyers). The latter was selected for an upcoming installation on the International Space Station

The effects of “pulling levers” focused deterrence strategies on crime

A number of American police departments have been experimenting with new problem-oriented policing frameworks to prevent gang and group-involved violence generally known as the “pulling levers” focused deterrence strategies. Focused deterrence strategies honor core deterrence ideas, such as increasing risks faced by offenders, while finding new and creative ways of deploying traditional and non-traditional law enforcement tools to do so, such as directly communicating incentives and disincentives to targeted offenders. Pioneered in Boston to halt serious gang violence, the focused deterrence framework has been applied in many American cities through federally sponsored violence prevention programs. In its simplest form, the approach consists of selecting a particular crime problem, such as gang homicide; convening an interagency working group of law enforcement, social-service, and community-based practitioners; conducting research to identify key offenders, groups, and behavior patterns; framing a response to offenders and groups of offenders that uses a varied menu of sanctions (“pulling levers”) to stop them from continuing their violent behavior; focusing social services and community resources on targeted offenders and groups to match law enforcement prevention efforts; and directly and repeatedly communicating with offenders to make them understand why they are receiving this special attention. These new strategic approaches have been applied to a range of crime problems, such as overt drug markets and individual repeat offenders, and have shown promising results in the reduction of crime. Objectives: To synthesize the extant evaluation literature and assess the effects of pulling levers focused deterrence strategies on crime. Conclusions: We conclude that pulling levers focused deterrence strategies seem to be effective in reducing crime. However, we urge caution in interpreting these results because of the lack of more rigorous randomized controlled trials in the existing body of scientific evidence on this approach

TOI-257b (HD 19916b): a warm sub-saturn orbiting an evolved F-type star

ABSTRACT We report the discovery of a warm sub-Saturn, TOI-257b (HD 19916b), based on data from NASA’s Transiting Exoplanet Survey Satellite (TESS). The transit signal was detected by TESS and confirmed to be of planetary origin based on radial velocity observations. An analysis of the TESS photometry, the Minerva-Australis, FEROS, and HARPS radial velocities, and the asteroseismic data of the stellar oscillations reveals that TOI-257b has a mass of MP = 0.138 ± 0.023 $\rm {M_J}$ (43.9 ± 7.3 $\, M_{\rm \oplus}$), a radius of RP = 0.639 ± 0.013 $\rm {R_J}$ (7.16 ± 0.15 $\, \mathrm{ R}_{\rm \oplus}$), bulk density of $0.65^{+0.12}_{-0.11}$ (cgs), and period $18.38818^{+0.00085}_{-0.00084}$ $\rm {days}$. TOI-257b orbits a bright (V = 7.612 mag) somewhat evolved late F-type star with M* = 1.390 ± 0.046 $\rm {M_{sun}}$, R* = 1.888 ± 0.033 $\rm {R_{sun}}$, Teff = 6075 ± 90 $\rm {K}$, and vsin i = 11.3 ± 0.5 km s−1. Additionally, we find hints for a second non-transiting sub-Saturn mass planet on a ∼71 day orbit using the radial velocity data. This system joins the ranks of a small number of exoplanet host stars (∼100) that have been characterized with asteroseismology. Warm sub-Saturns are rare in the known sample of exoplanets, and thus the discovery of TOI-257b is important in the context of future work studying the formation and migration history of similar planetary systems

Conclusions From the History of Research into the Effects of Police Force Size on Crime—1968 through 2013: A Historical Systematic Review

Objectives: We describe and explain how the findings from nonexperimental studies of the relationship between police force size and crime have changed over time. Methods: We conduct a systematic review of 62 studies and 229 findings of police force size and crime, from 1971 through 2013. Only studies of U.S. policing and containing standard errors of estimates were included. Using the robust variance estimation technique for meta-analysis, we show the history of study findings and effect sizes. We look at the influence of statistical methods and units of analysis, and time period of studies’ data, as well as variation in police force size over time. Results: Findings vary considerably over time. However, compared to research standards and in comparison to effect sizes calculated for police practices in other meta-analyses, the overall effect size for police force size on crime is negative, small, and not statistically significant. Changes in research methods and units of analysis cannot account for fluctuations in findings. Finally, there is extremely little variation in police force size per capita over time, making it difficult to estimate the relationship with reliability. Conclusions: This line of research has exhausted its utility. Changing policing strategy is likely to have a greater impact on crime than adding more police

Revisiting Broken Windows Theory: A Test Of The Mediation Impact Of Social Mechanisms On The Disorder-Fear Relationship

Broken windows theory predicts that disorder signals a lack of neighborhood control, sparks fear of crime, and sets off a chain reaction ultimately resulting in crime. Support has been found for the disorder-fear link, but the present study argues that this link is actually intended to be indirect-perceived loss of control is what should cause fear. Methods: Hierarchical linear models and structural equation models test four hypotheses regarding whether social cohesion and expectations for social control mediate the disorder-fear relationship. Results: Results support partial mediation. Conclusion: Results suggest confirmation of a portion of broken windows theory, in that disorder may inspire fear partially as a result of its detrimental impact on neighborhood cohesion and shared expectations for social control

The drug market intervention approach to overt drug markets

Purpose: The purpose of this research was to assess the impact of a strategic intervention intended to eliminate overt drug markets and their associated crime and disorder and to improve relationships between the police and local neighborhood residents. Design/Methods/Approach: The study included a process assessment of the nature of the intervention as well as an impact assessment based on trends in crime, calls-for-police-service and interviews with residents. The research occurred in the U.S. and examined a pilot program in High Point, North Carolina and subsequent implementation in Rockford, Illinois and Nashville, Tennessee. Findings: The paper presents a description of the intervention. Additionally, outcome data indicate that the intervention was related to reductions in crime and calls-forpolice service in all three communities. Raw declines were observed for violent, property and drug offenses with the declines consistently being statistically significant for drug offenses. Additionally, local residents described improved quality of neighborhood life and increased satisfaction with the police. Research limitations/implications: The results suggest that the so-called High Point Drug Market Intervention holds significant promise for addressing overt drug markets. However, the analysis is limited in that the comparison group is the citywide trend in crime as opposed to true comparison sites. Future studies utilizing quasi-experimental or experimental designs are needed to rule out potential rival explanations. Practical implications: The Drug Market Intervention appears to be a promising practice offering police officials a strategy for longer term impact on neighborhood safety and quality of life than has been the case with traditional crackdowns on drug markets. Originality/Value: This paper offers the evaluation results from three sites on a drug market intervention that has gained considerable attention, at least within the U.S