A Comparison of Thresholding Methods for Forensic Reconstruction Studies Using Fluorescent Powder Proxies for Trace Materials

Image segmentation is a fundamental precursor to quantitative image analysis. At present, no standardised methodology exists for segmenting images of fluorescent proxies for trace evidence. Experiments evaluated (i) whether manual segmentation is reproducible within and between examiners (with three participants repeatedly tracing three images) (ii) whether manually defining a threshold level offers accurate and reproducible results (with 20 examiners segmenting 10 images), and (iii) whether a global thresholding algorithm might perform with similar accuracy, while offering improved reproducibility and efficiency (16 algorithms tested). Statistically significant differences were seen between examiners’ traced outputs. Manually thresholding produced good accuracy on average (within ±1% of the expected values), but poor reproducibility (with multiple outliers). Three algorithms (Yen, MaxEntropy, and RenyiEntropy) offered similar accuracy, with improved reproducibility and efficiency. Together, these findings suggest that appropriate algorithms could perform thresholding tasks as part of a robust workflow for reconstruction studies employing fluorescent proxies for trace evidence.     

EVIDENTIARY ISSUES WITH PARENTAL ALIENATION SYNDROME

Expert testimony on unsubstantiated social science syndromes such as the Parental Alienation Syndrome (PAS) has been increasingly admitted in courtrooms across the United States. This is a problem because a trier of fact is making a determination based on theories that are inaccurate or incorrect. To remedy this, the standards of admissibility for expert testimony must be heightened. The broad discretion given to trial judges in determining admissibility should be reevaluated and a new rule of evidence for social science testimony should be adopted.     

Policy on innovation in Australia: Divergence in definitions,problems, and solutions

Innovation has joined the mainstream in many nations as governments search for new ways to tackle challenging societal and economic problems. But Australia is seen to be lagging on innovation policy. Is this related to how governments define innovation? What do they regard as the problem they are addressing? What proposed solutions follow from this? This paper examines how Australian governments have defined innovation over four decades, signalling their policy intentions about how to make the nation more innovative. Definitions of innovation are analysed using 79 Australian (national level) policy documents published from 1976 to 2019. Close reading of these documents suggests two main definitions: innovation as technology, and innovation as culture. Topic modelling uncovers more differentiated themes, shows how definitions change over time, and demonstrates an association between definitions and political parties in government. The divergent approaches suggest a lack of coherence and continuity to policy on innovation in Australia.

Points for practitioners

• Innovation has expanded and broadened in its definition and governments and policymakers have paid increasing attention to it.
• In Australia, there are two main definitions of innovation used in policy—one related to technology and one related to culture.
• The technology view of innovation can be further divided into a focus on businesses or a focus on research and development (R&D).
• Different innovation definitions, problems, and solutions dominate at different times, with Coalition governments tending to favour business and technology over culture, and Labor governments doing the opposite.
• There are divergent approaches to policy on innovation in Australia which suggest a lack of coherence and consistency in policy over the long term.