Comparison of Open Source Code when Updating using the Damerau-Levenshtein Distance

The paper describes a text comparison problem that arises during the update of open source programs in the presence of user changes. An algorithm based on calculating the Damerau — Levenshtein distance is used to correctly match the lines of two texts. The main difference between the proposed algorithm and the classical one is that the weights of such operations as insert, delete, replace, and permute are not constants, but depend on the values of individual text elements and their location. The paper also describes the functionality that allows the programmer to simplify the task of analyzing changes in program texts. The functionality is based on dynamic control of the comparison process, during which the programmer can manually establish correspondences between the compared texts. The effectiveness of the proposed method is checked when updating modules in the 1C:Enterprise system.

Small Longest Tandem Scattered Subsequences

We consider the problem of identifying tandem scattered subsequences within a string. Our algorithm identifies a longest subsequence which occurs twice without overlap in a string. This algorithm is based on the Hunt-Szymanski algorithm, therefore its performance improves if the string is not self similar, which occurs naturally on strings over large alphabets. Our algorithm relies on new results for data structures that support dynamic longest increasing sub-sequences. In the process we also obtain improved algorithms for the decremental string comparison problem.

On seeking souls in brain graphs: fancy neuroimaging analysis gone wrong?

An increasing number of studies is currently focusing on ‘personality neuroscience’, a term labeling the research aimed at neuroimaging correlates of inter-individual temperament and character variability. Among other methods, a graph theoretical analysis of the functional connectivity in resting state functional magnetic resonance imaging data was applied in a recent study by Gao et al. (2013, Frontiers in Human Neuroscience). This paper aims to replicate this study and extends the original statistical methods in order to demonstrate the effect of multiple comparison problem. In contrast to the original study, five personality dimensions were obtained in the revised ‘Big Five’ Personality Inventory. Using a larger sample (84 subjects) and an equivalent data analysis procedure, we obtained widely disagreeing results compared to the original study. While the Gao et al. reported a range of significant correlations between personality dimensions and some of the network metrics, we failed to replicate any significant correlations when FDR testing was applied. These results demonstrate that as with other neuroimaging studies, appropriate control of multiple comparison problem should be meticulously applied in order to prevent such false alarms in research into neurological substrates of personality differences. Of course, we do not attempt to disprove the existence of some link between personality and brain’s intrinsic functional architecture. Nevertheless, this link is very likely much more subtle and elusive than was suggested in previous studies.

Preschool children's verbal problem solving skills and the types of verbal problems that teachers present to children

This research aims to investigate the verbal problem solving skills of preschool children in mathematics according to the type of problem and the type of unknown in the problem; and to determine the perspectives of the teachers about the implementation process of these problems. The mix method was used in this study. The sample consisted of 50 preschool children and 6 preschool teachers of these children. In the research, the data were collected by using a problem solving test and a semi-structured interview form. The data were obtained via individual interviews with children and teachers. According to the results of the research, it was concluded that in all type of problems the children were found to be more successful at separation, joining, part- whole problem types than comparison problem types. It was concluded that it was easier for children to answer the problems with ending unknown than the problems with initial unknown and change unknown. In the result of the interviews with teachers, it was revealed that most of the teachers did not use comparison problem type and the problems with initial unknown. It was determined that most of the teachers were not aware of all types of problems.