Some New Aspects of 2 × 2 Table Measures and Their Applications

The paper deals with the analysis of 2 × 2 table measures and describes several new possibilities for applying them. An estimate is given for HELLMICH's asymmetric K-measure and a possible extension of the contingency concept in a special 2×2 case is presented. The concept introduced and the recommended computer application of the 2×2 table measures is supported by new results obtained for the relationship between jaw joint pains and noises examined earlier by F. SCHMID and C. ZSCHEGE. With a larger number of observations the opportunity arises for a deeper analysis of this dental problem using path analysis. The plan of evaluation and the conncetion between the variables examined is illustrated by a path-diagram. The association tables determined on the basis of the (C) values introduced during the examination of jaw joint disturbances using association analysis draw attention to the special role of the left side of mastication. The paper raises ideas for further generalisations and indicates where further research is needed.     

Comparative study of the antennal lobes and their afferent pathway in the worker bee and the drone (Apis mellifera)

Summary The topography of the antennal afferent path-ways was studied comparatively in the worker bee and the drone of Apis mellifera L. by cellular marking, following localized application of cobalt chloride to the cut end of one antenna. This study dealt principally with the first relay of the afferent pathway in the glomeruli of the antennal lobe. The counting and measurement of all the glomeruli were performed on 5 worker bees and 5 drones. An important sexual dimorphism, represented by 4 large and easily identifiable glomerular complexes, was demonstrated in the drone. In both worker bee and drone, four main regions of the glomerular neuropil were distinguished according to corresponding afferent bundles. The worker possessed 166 glomeruli and the drone 103. The number, position and dimensions of the glomeruli indicated that the glomerular organization was unvarying in worker bees and in drones. Concerning the internal structure of the glomeruli, two types were distinguished: the great majority (95%) exhibited a cortical layer, whereas in the 7 posterior glomeruli the synaptic fields of association seemed to be scattered throughout the whole volume. The main results of this work (glomerular invariance, sexual dimorphism) support the hypothesis of the functional unit of the glomeruli.Unité de Recherche Associée au CNRS, UA 483     

A new dissimilarity measure and a new optimality criterion in phytosociological classification

A new dissimilarity measure, Uppsala dissimilarity, is proposed. It is a Manhattan-type measure in between the Canberra and Gower measures, based on the differences between scores in relevés compared, but it also takes both the sums of scores and the difference between maximum and minimum score into account. The measure is considered realistic for phytosociological material.A new optimality criterion has been developed after unsatisfactory results had been obtained with the DOL criterion (Popma et al. 1983) which was developed previously by our group. Problems with DOL were especially met when the criterion was applied to the distribution of only one species over the cluster array obtained. The new criterion takes both internal cluster homogeneity and between-cluster dissimilarity into account. Between-cluster dissimilarity is calculated for all other clusters and not only for the nearest neighbour, as in DOL. The new criterion has both an unweighted form: SOM, and a form with weighting for cluster size: SWOM.This new criterion was successfully applied to the evaluation of the sharpness of distribution of individual species over cluster arrays, under the name of SIM: species indication measure and SWIM, species weighted indication measure.The measures were applied to some test data. Differences between the unweighted and weighted forms were found which could not be easily interpreted.Some remarks are made on the coherence of d-SAHN and h-SAHN approaches in agglomerative clustering within the new strategy proposed.Abbreviations DOL = Detection of Optimal Level - S(W)IM = Species (Weighted) Indication Measure - S(W)OM = Standardized (Weighted) Optimality Measure - UD = Uppsala Dissimilarity measure - WPGMA = Weighted Pair-Group Method Average linking clustering - SAHN = Sequential Agglomerative Hierarchical Non-overlapping clustering     

Depletion interaction in colloid/polymer mixtures: application of density functional theory

Insert-route density functional approach (IRDFT), modified fundamental measure theory (MFMT) and thermodynamic perturbation theory (TPT1 and TPT2) are combined to study the depletion force between colloidal particles in hard sphere/hard sphere chain mixtures which represent a model of systems containing colloids dispersed in an athermal polymer solution. The predicted results are compared to simulations showing the reliability of the method used which captures the main characteristics of depletion interaction between colloids induced by polymers. Results of TPT2 are slightly more repulsive and better than that of TPT1 especially when the inter-particle distance is small than the diameter of polymer segment indicating the essential influence of the three-body correlations. Effects of the polymer density, polymer chain length and size ratio of colloid to polymer segment on the depletion force are studied in detail. Due to a little deterioration of the prediction in the high density region, further improvement is anticipated to better balance the competition between the excluded-volume effect and the chain connectivity.     

On the selection of thresholds for predicting species occurrence with presence‐only data

Presence‐only data present challenges for selecting thresholds to transform species distribution modeling results into binary outputs. In this article, we compare two recently published threshold selection methods (maxSSS and maxF_pb) and examine the effectiveness of the threshold‐based prevalence estimation approach. Six virtual species with varying prevalence were simulated within a real landscape in southeastern Australia. Presence‐only models were built with DOMAIN, generalized linear model, Maxent, and Random Forest. Thresholds were selected with two methods maxSSS and maxF_pb with four presence‐only datasets with different ratios of the number of known presences to the number of random points (KP–RP_ratio). Sensitivity, specificity, true skill statistic, and F measure were used to evaluate the performance of the results. Species prevalence was estimated as the ratio of the number of predicted presences to the total number of points in the evaluation dataset. Thresholds selected with maxF_pb varied as the KP–RP_ratio of the threshold selection datasets changed. Datasets with the KP–RP_ratio around 1 generally produced better results than scores distant from 1. Results produced by We conclude that maxF_pb had specificity too low for very common species using Random Forest and Maxent models. In contrast, maxSSS produced consistent results whichever dataset was used. The estimation of prevalence was almost always biased, and the bias was very large for DOMAIN and Random Forest predictions. We conclude that maxF_pb is affected by the KP–RP_ratio of the threshold selection datasets, but maxSSS is almost unaffected by this ratio. Unbiased estimations of prevalence are difficult to be determined using the threshold‐based approach.     

Ecological total-factor energy efficiency of China’s energy intensive industries

This paper uses a meta-frontier slack-based DEA model to measure the ecological total-factor energy efficiency as well as the energy conservation potential of China’s four energy intensive subsectors. We incorporate both desirable and undesirable output together in the period, 2000–2013. The conclusions are: firstly, under the meta-frontier, the four subsectors of energy intensive industries have low average level of ecological total-factor energy efficiencies. They are 0.137, 0.212, 0.238, and 0.307 in the non-metallic mineral products manufacturing industry, raw chemical materials and chemical products manufacturing industry, smelting and pressing of ferrous metals industry, and smelting and pressing of non-ferrous metals industry, respectively. Secondly, the ecological energy efficiency in East China is the highest among three regions. Central China and West China are behind, but they are extremely close to each other. Thirdly, East China almost has no technology gap pertaining to energy efficiency, while Central China and West China almost have the same gap. Finally, Sichuan is considered to be the best province in West China under group frontier due to its perform in the three energy intensive subsectors. For Central and East China, no province has higher ecological energy efficiency in more than two energy intensive subsectors.