Circuits and subterfuge: Emily Wardill and the body imaginary

Article on the works of London based artist Emily Wardill

Searchability of Networks

We investigate the searchability of complex systems in terms of their interconnectedness. Associating searchability with the number and size of branch points along the paths between the nodes, we find that scale-free networks are relatively difficult to search, and thus that the abundance of scale-free networks in nature and society may reflect an attempt to protect local areas in a highly interconnected network from nonrelated communication. In fact, starting from a random node, real-world networks with higher order organization like modular or hierarchical structure are even more difficult to navigate than random scale-free networks. The searchability at the node level opens the possibility for a generalized hierarchy measure that captures both the hierarchy in the usual terms of trees as in military structures, and the intrinsic hierarchical nature of topological hierarchies for scale-free networks as in the Internet.Comment: 9 pages, 10 figure

Policy regarding the sequential lineup is not informed by probative value but is informed by ROC analysis.

It is important to determine if switching from simultaneous to sequential lineups affects response bias (the inclination to make an identification from a lineup), discriminability (the ability to distinguish between innocent and guilty suspects), or both. Measures of probative value cannot provide such information; receiver operating characteristic analysis can. Recent receiver operating characteristic analyses indicate that switching to sequential lineups both induces more conservative responding and makes it more difficult to distinguish between innocent and guilty suspects. If more conservative responding is preferred (i.e., if policymakers judge that the harm associated with the reduction of correct identifications is exceeded by the benefit associated with the reduction in false identifications), recent data indicate that this result can be achieved without a loss of discriminability by using the simultaneous lineup procedure in conjunction with a more conservative decision criterion.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

A simple model for self organization of bipartite networks

We suggest a minimalistic model for directed networks and suggest an application to injection and merging of magnetic field lines. We obtain a network of connected donor and acceptor vertices with degree distribution $1/s^2$, and with dynamical reconnection events of size $\Delta s$ occurring with frequency that scale as $1/\Delta s^3$. This suggest that the model is in the same universality class as the model for self organization in the solar atmosphere suggested by Hughes et al.(PRL {\bf 90} 131101)

Calculating the random guess scores of multiple-response and matching test items

For achievement tests, the guess score is often used as a baseline for the lowest possible grade for score to grade transformations and setting the cut scores. For test item types such as multiple-response, matching and drag-and-drop, determin-ing the guess score requires more elaborate calculations than the more straight-forward calculation of the guess score for True-False and multiple-choice test item formats. For various variants of multiple-response and matching types with respect to dichotomous and polytomous scoring, methods for determining the guess score are presented and illustrated with practical applications. The implica-tions for theory and practice are discussed

Do the clothes make the criminal? The influence of clothing match on identification accuracy in showups

Showups, a single suspect identification, are thought to be a more suggestive procedure than traditional lineups by the U.S. Supreme Court and social science researchers. Previous research typically finds that a clothing match in showup identifications increases false identifications. However, these experiments do not allow for a determination of whether this increase arises from a change in response bias, reduced discriminability, or both. In the present study, participants viewed a mock crime video and made a showup identification with either a clothing match or mismatch. Contrary to prior research, the best discriminability occurred when the guilty and innocent suspects wore clothing that matched the clothing worn during the crime. A clothing match also resulted in a more liberal response bias. The results are consistent with the principle of encoding specificity and the outshining hypothesis, as instantiated in the item, context, ensemble theory. Practical implications are discussed

Receiver Operating Characteristic Analysis and Confidence-Accuracy Characteristic Analysis in Investigations of System Variables and Estimator Variables that Affect Eyewitness Memory

Two graphical techniques, receiver operating characteristic (ROC) analysis and what might be termed “confidence–accuracy characteristic” (CAC) analysis, are important tools for investigating variables that affect the accuracy of eyewitness identifications (e.g., type of lineup, exposure duration, same-race vs. other-race identifications, etc.). CAC analysis (a close relative of calibration analysis) consists of simply plotting suspect identification accuracy for each level of confidence. Two parties interested in the results of such investigations include (1) legal policymakers (e.g., state legislators and police chiefs) and (2) triers of guilt and innocence (e.g., judges and jurors). Which type of analysis is the most relevant to which party? The answer is largely a matter of whether the variable in question is a system variable or an estimator variable. ROC analysis, which measures discriminability, is critical for understanding system variables that affect eyewitness accuracy (e.g., the best lineup procedures). Thus, policymakers should be particularly attuned to the results of ROC analysis when making decisions about those variables. CAC analysis, which directly measures the confidence–accuracy relationship for suspect IDs, is critical for understanding the effect of estimator variables on eyewitness accuracy (e.g., exposure duration). Thus, triers of guilt and innocence should be particularly attuned to the results of CAC analysis. The utility of both analyses to system and estimator variables is illustrated by examining both types of analyses on previously published experiments and new experiments