Large Number of Rare Events: Diversity Analysis in Multiple Choice Questionnaires and Related Topics

<p>The statistical analysis of a large number of rare events, (LNRE), which can also be called statistical theory of diversity, is the subject of acute interest both in statistical theory and in numerous applications. A careful eye will quickly see the presence of a large number of very rare objects almost everywhere: large numbers of rare species in ecosystems, large numbers of rare opinions in any opinion pool, large numbers of small admixtures in any solution and large numbers of rare words in any text are only few examples. In studying such objects, the interest for mathematical statisticians lies in the fact that most of the frequencies are small and, therefore, difficult to deal with. It is not immediately clear how one should be able to derive consistent and reliable inference from a large number of such frequencies. In this thesis we study the diversity of questionnaires with multiple answers. It has been demonstrated that this is a particular model of LNRE theory. In our analysis, the theories of large deviation, contiguity and Edgeworth expansion were employed, and limit theorems have been established.</p>

Large Number of Rare Events: Diversity Analysis in Multiple Choice Questionnaires and Related Topics

<p>The statistical analysis of a large number of rare events, (LNRE), which can also be called statistical theory of diversity, is the subject of acute interest both in statistical theory and in numerous applications. A careful eye will quickly see the presence of a large number of very rare objects almost everywhere: large numbers of rare species in ecosystems, large numbers of rare opinions in any opinion pool, large numbers of small admixtures in any solution and large numbers of rare words in any text are only few examples. In studying such objects, the interest for mathematical statisticians lies in the fact that most of the frequencies are small and, therefore, difficult to deal with. It is not immediately clear how one should be able to derive consistent and reliable inference from a large number of such frequencies. In this thesis we study the diversity of questionnaires with multiple answers. It has been demonstrated that this is a particular model of LNRE theory. In our analysis, the theories of large deviation, contiguity and Edgeworth expansion were employed, and limit theorems have been established.</p>

How to choose a fair delegation?

This paper analyzes how to choose a delegation, a committee to represent a society such as in a peace conference. We propose normative conditions and seek Pareto optimal, consistent, neutral, and non-manipulable ways to choose a delegation. We show that a class of threshold rules is characterized by these criteria. The rules do not choose a fixed number of delegates, but instead require different sizes of delegations, depending on the heterogeneity in society. Therefore the resulting delegations are very inclusive, and with t delegates the ratio of individuals whose opinions are not included is always below "Equation missing". For instance, a delegation of size two should have at least 75% support from the society and therefore only less than 25% of the opinion pool can be neglected.

What Makes a Front-of-Pack Nutritional Labelling System Effective: The Impact of Key Design Components on Food Purchases

The relative impacts on food purchases of many alternative front-of-pack nutritional labelling systems were tested, with various methods—from opinion pool to nationwide experiments. Clearly, some systems induce better purchasing responses, having better nutritional impacts on food baskets. Nonetheless, we still ignore what the ingredients of an efficient label are. Here, we propose guidance for label designers. To do so, we first propose a typology that breaks down established labelling systems into four elementary components: Directiveness, Scope and Gradation, Set of Reference and Sign. On this basis, we then build seven alternative generic labelling systems that we test in a framed-field experiment enabling us to measure the effect of each component on food purchases in isolation. Our results show that an effective front-of-pack labelling system should be Food-Directive (instead of Diet-Directive) and be displayed on both healthy and unhealthy food. The reference set, which is across categories or within categories, produces the same average nutrition score but generates contrasting behavioural responses.

A telemedicine communication exchange network in Gorno-Badakhshan Autonomic Oblast in collaboration with Swiss Surgical Teams

Introduction The purpose of this article is to report on the implementation of a telemedicine network serving as a second opinion pool for a surgeon in a remote area of a developing country. Methods This study involved an international collaboration between two members of Swiss Surgical Teams at a tertiary referral hospital and a surgeon in a remote area in Gorno-Badakhshan Autonomic Oblast, Tajikistan, which established a second opinion pool discussing diagnostics and therapeutic options via a messenger application. A retrospective analysis of response times was performed using a series of 50 challenging cases. Results The median time to receive a first telemedical response from any of the two contacts was 24 min (interquartile range 6–73). Urgent and emergent pathologies accounted for 57% of cases. The suggested treatment was carried out in 90% ( n = 44) of cases. Conclusions Timely and convenient telemedicine support to provide diagnostic and therapeutic reassurance and improve treatment quality for patients presenting to a general and vascular surgeon in the large and remote region of Gorno-Badakhshan Autonomic Oblast can be installed via a messenger application.

A Review of Probabilistic Opinion Pooling Algorithms with Application to Insider Threat Detection

We retrospectively explore the effectiveness of various probabilistic opinion pools against a set of insider threat detection modeling data from a recently completed, multiyear, sponsored research effort. We explored four opinion pools: the linear opinion pool (likely the most popular), the beta-transformed linear opinion pool, the geometric opinion pool, and a multiplicative method based on odds called Bordley’s formula. The data for our study came from our recent work in the inference of insider threats for our research sponsor. In this work, we created a multimodeling inference enterprise modeling (MIEM) process to either predict threats within a population or, given the threats, predict how well the enterprise system can detect those threats. As part of larger research challenges designed by the research sponsor, we applied the MIEM process quarterly to respond to a sequence of varying challenge problems (CPs). Via MIEM, we developed multiple, independent computation forecast models. These models generated certainty intervals to answer CP questions. These intervals were fused into a single interval for each question via an expert panel prior to submission. The sponsors scored the responses against ground truth. In this paper, we (a) ask which pooling functions work best on these data and consider why, and (b) compare this performance to the actual submissions to determine if one of the pooling functions performed better than our judgment-based fusion.