Advances in offender profiling: A systematic review of the profiling literature published over the past three decades

Abstract Despite the immense popularity of offender profiling as both a topic of fascination for the general public as well as an academic field of study, concerns have been raised about the development of this area of scientific inquiry. The present study provides a preliminary step towards moving the field forward as it reviews the type and quality of studies dealing with offender profiling over the past 31 years. Based on a content analysis of 132 published articles, the review indicates that researchers investigating this phenomenon rarely publish multiple articles, and they are generally reported across many different journals, thereby making knowledge synthesis and knowledge transfer problematic. In addition, the majority of papers published in the area are discussion pieces (e.g., discussing what profiling is, how profiles are constructed, and when profiling is useful), despite the fact that the processes underlying offender profiling are still not well understood. Finally, although peer-reviewed articles exploring this topic have steadily increased, the statistical sophistication of these studies is sorely lacking, with most including no statistics or formal analyses of data. Suggestions for future research and recommendations to streamline efforts in this field are provided based on the results of this review

Investigating Dunedin whistlers using volcanic lightning

Whistlers detected at Dunedin, New Zealand are an anomaly: there is little lightning around Dunedin's conjugate point yet whistlers appear in relatively large numbers. These surplus whistlers have consequently inspired investigations into their origins. Dunedin's lightning-sparse conjugate point lies in the Aleutian Islands, a region populated with active volcanoes. Their presence has allowed us to perform a novel analysis: the correlation of whistlers to volcanic lightning. We report on our investigation, which successfully yielded the first observations of "volcanic whistlers." It was found that the single July 2008 Mount Okmok eruption had an impressive effect on the number of whistlers at Dunedin. The eruptions at Mount Redoubt in 2009 also caused a sporadic flow of whistlers in Dunedin

The role of substance abuse factors in predicting recidivism: A meta-analysis

The present study examined the utility of several substance abuse factors in predicting general and violent recidivism. A quantitative meta-analytic review was used to examine five substance abuse predictor categories. Forty-five studies were selected for inclusion, producing 116 individual effect size estimates. Overall, the meta-analysis generated a weighted mean effect size of .10 between substance abuse and general recidivism. A combined alcohol and/or drug problem predictor category yielded the highest mean effect size (Mz+ = .22), followed by drug abuse (Mz+ = .19), parental substance abuse (Mz+ = .13), and alcohol abuse (Mz+ = .12). Interestingly, substance abuse convictions were not related to general recidivism (Mz+ = -.02). The results not only confirm the overall predictive relationship between substance abuse and criminal recidivism but also suggest that appropriately identifying the type of substance abuse factor may enhance the predictive utility of several risk assessment instruments

Decay of whistler-induced electron precipitation and cloud-ionosphere electrical discharge Trimpis: observations and analysis

There are two distinctly different causes of phase and amplitude perturbations of subionospheric VLF transmissions (termed “Trimpis”): (1) ionization enhancement in the ionospheric D region due to whistler-induced electron precipitation (WEP) and (2) modifications to the ionosphere induced directly by lightning. The latter appear to be subdivided into ionization anomalies produced by cloud-ionosphere electrical discharge (CID), or “red sprites,” and heating anomalies which may not involve ionization at all. Here we consider only Trimpis (WEP and CID) produced by ionization and find that the magnitude of the Trimpi perturbation (which includes both the amplitude and phase perturbations) of both Trimpi types decays logarithmically rather than exponentially with time. While this has been previously shown for CID Trimpis, the decay of WEP Trimpis was previously thought to be exponential

VLF scattering from red sprites: application of numerical modelling

Red sprites were discovered by chance in 1989 when a low-light TV system was pointed above an active thunderstorm. Red sprites are associated with columns of ionization in the Earth-ionosphere waveguide, from above the thunderstorm into the D region of the ionosphere. The ionized columns have been detected through “VLF sprites,” perturbations of the phase and/or amplitude of subionospheric VLF transmissions, which can be used to study the electrical properties of red sprites. There is extensive experimental evidence that VLF sprites may involve wide scattering angles and can produce back scattered radiation. Here we present a numerical and theoretical study of me scattering of subionospheric VLF transmissions caused by the plasma columns associated with red sprites. Comparison of the VLF scattering from sprites is made between a non-Born rigorous model which assumes the sprites are infinite columns of constant conductivity, and a three dimensional Born scattering code. Both formulations show excellent agreement with one another. The formulations predict VLF sprites similar to those experimentally observed for all scattering angles. This shows that the conclusions of previous studies into VLF sprites making use of the non-Born formulations of Rodger et al. [1997a, b] are valid. The modeling provides strong evidence that red sprite plasma is highly ionized in comparison with the ambient nighttime ionosphere, being nearly 5 orders of magnitude greater than the ambient at some heights

VLF scattering from red sprites: Vertical columns of ionization in the Earth-ionosphere waveguide

Red sprites were discovered by chance in 1989 when a low-light TV system was pointed above an active thunderstorm. Optically, they are observed as clusters of short-lived (∼50 ms) pinkish-red luminous events, sometimes stretching from ∼40 to ∼85 km altitude. Red sprites are associated with ionization in the Earth-ionosphere waveguide, which can persist for up to ∼100 s at higher altitudes. The structured ionization associated with red sprites has been observed through “VLF sprites,” perturbations of the phase and/or amplitude of subionospheric VLF transmissions, which can be used to study the electrical properties of the red sprite plasma. Previous theoretical studies have simplified the problem by assuming the red sprite associated ionizations were columns of infinite length, or inside a “flat-Earth” waveguide. In this paper we present an approach for examining the scattering of VLF transmissions by a finite-length column of ionization inside the Earth-ionosphere waveguide, including the effect of realistic curvature of the waveguide. These expressions are applied to the detection and study of red sprites by assuming that the associated ionization can be treated as a (cluster of) truncated columns in the Earthionosphere waveguide. An example calculation is presented, examining the farthest distance from the red sprite from which it might be detected as a VLF sprit

Sprite observations in the Northern Territory of Australia

Sprites, a form of brief luminous discharge in the upper atmosphere above a thunderstorm, were observed and imaged on two video cameras in Australia's Northern Territory. These were the first such ground-based observations made outside the United States. Sprite discharges typically took place between the altitudes of 50 km and 80 km and spanned an average width of 44 km. Many of the sprite events were of long duration, with an average of 145 ms. These spatial and temporal features were similar to those observed from the ground and the air in the United States. During the longer events, some luminous discharge elements were observed to decay as other new elements formed. As the new elements were often laterally displaced from the old, the sprites sometimes appeared to dance across the sky. This phenomenon has been observed in Colorado and named “dancing sprites.” The lateral progression of sprite elements observed in the Northern Territory was overwhelmingly in one direction and covered distances of up to 90 km

Tropical daytime lower D-region dependence on sunspot number

Observed phases and amplitudes of VLF radio signals propagating on (near) tropical all-sea paths, both short, ∼300 km, and long, ∼10 Mm, are used to find daytime parameter changes for the lowest edge of the (D-region of the) Earth's ionosphere as the solar cycle advanced from a very low sunspot number of ∼5 up to ∼60, in the period 2009–2011. The VLF phases, relative to GPS 1-s pulses, and amplitudes were measured ∼100 km from the transmitter, where the direct ground wave is very dominant, ∼300 km from the transmitter, near where the ionospherically reflected waves form a (modal) minimum with the ground wave, and ∼10 Mm away where the lowest order waveguide mode is fully dominant. Most of the signals came from the 19.8 kHz, 1-MW transmitter, NWC, North West Cape, Australia, propagating ENE, mainly over the sea, to the vicinity of Karratha and Dampier on the NW coast of Australia and then on to Kauai, Hawaii, ∼10.6 Mm from NWC. Observations from the 8.1-Mm path NPM (21.4 kHz, Hawaii) to Dunedin, NZ, are also used. The sunspot number increase from ∼5 to ∼60 was found to coincide with a decrease in the height, H′, of the midday tropical ionosphere by 0.75 ± 0.25 km (from H′ ≈ 70.5 km to H′ ≈ 69.7 km) while the sharpness, β increased by 0.025 ± 0.01 km−1 (from β ≈ 0.47 km−1 to β ≈ 0.49 km−1) where H′ and β are the traditional height and sharpness parameters used by Wait and by the U.S. Navy in their Earth-ionosphere VLF radio waveguide programs