A note on ROC analysis and non-parametric estimate of sensitivity

In the signal detection paradigm, the non-parametric index of sensitivity A ′, as first introduced by Pollack and Norman (1964), is a popular alternative to the more traditional d ′ measure of sensitivity. Smith (1995) clarified a confusion about the interpretation of A ′ in relation to the area beneath proper receiver operating characteristic (ROC) curves, and provided a formula (which he called A ′′) for this commonly held interpretation. However, he made an error in his calculations. Here, we rectify this error by providing the correct formula (which we call A ) and compare the discrepancy that would have resulted. The corresponding measure for bias b is also provided. Since all such calculations apply to “proper” ROC curves with non-decreasing slopes, we also prove, as a separate result, the slope-monotonicity of ROC curves generated by likelihood-ratio criterion.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45761/1/11336_2003_Article_1119.pd

Dynamic pursuit with a bio-inspired neural model

In this paper we present a bio-inspired connectionist model for visual perception of motion and its pursuit. It is organized in three stages: a causal spatio-temporal filtering of Gabor-like type, an antagonist inhibition mechanism and a densely interconnected neural population. These stages are inspired by the neural treatment and the interactions of the primary visual cortex, middle temporal area and superior visual areas. This model has been evaluated on natural image sequences

Visitor satisfaction analysis as a tool for park managers: a review and case study

Visitor satisfaction has been an important area for leisure research since the 1960s and more recently for park management. A number of approaches have been adapted from consumer research including importance-performance analyses, gap analyses, threshold performance targets and overall satisfaction. This paper reviews these approaches with respect to park management. It then draws on focus group research with protected area agency staff to obtain their views on the usefulness and robustness of the analyses associated with these approaches. Yanchep National Park (Western Australia) was used as a case study, with the results from a recent visitor survey providing the data for satisfaction analyses. To provide a more accurate summary of the range in results, confidence intervals accompanied the results to illustrate the variation in responses. The analyses emphasize the importance for park managers of accessible, usable data on visitor satisfaction