Quantifying 'causality' in complex systems: Understanding Transfer Entropy

'Causal' direction is of great importance when dealing with complex systems. Often big volumes of data in the form of time series are available and it is important to develop methods that can inform about possible causal connections between the different observables. Here we investigate the ability of the Transfer Entropy measure to identify causal relations embedded in emergent coherent correlations. We do this by firstly applying Transfer Entropy to an amended Ising model. In addition we use a simple Random Transition model to test the reliability of Transfer Entropy as a measure of `causal' direction in the presence of stochastic fluctuations. In particular we systematically study the effect of the finite size of data sets

Mutual information based measures on complex interdependent networks of neuro data sets

We assume that even the simplest model of the brain is nonlinear and ‘causal’. Proceeding with the first assumption, we need a measure that is able to capture nonlinearity and hence Mutual Information whose variants includes Transfer Entropy is chosen. The second assumption of ‘causality’ is defined in relation to prediction ala Granger causality. Both these assumptions led us to Transfer Entropy. We take the simplest case of Transfer Entropy, redefine it for our purposes of detecting causal lag and proceed with a systematic investigation of this value. We start off with the Ising model and then moved on to created an amended Ising model where we attempted to replicate ‘causality’. We do the same for a toy model that can be calculated analytically and thus simulations can be compared to its theoretical value. Lastly, we tackle a very interesting EEG data set where Transfer Entropy shall be used on different frequency bands to display possible emergent property of ‘causality’ and detect possible candidates for causal lag on the data sets.Open Acces

New distributional record of Mymar taprobanicum Ward, 1875 (Hymenoptera: Mymaridae) from Malaysian Borneo

Knowledge of the microhymenopteran fauna of the Chalcidoid family, Mymaridae of Malaysia is very limited. This report provides a new distributional record of Mymar taprobanicum Ward, 1875, from Sarawak, East Malaysian Borneo. Four male specimens were collected through yellow pan traps in a residential area in Kuching in December 2016. Although widely known as an important parasitoid of rice pests, this species has never been reported from East Malaysian Borneo prior to this report

The Dualities of Endurance: A Collaborative Historical Archaeology of Ethnogenesis at Brothertown, 1780-1910

The Brothertown Indian community formed in the late 18th century when segments of several tribal groups from coastal northeastern North America broke away from their home settlements to move west together. What united the community was a shared belief in Christianity, a dedication to practices of agriculture, and hopes of escaping the land politics and corrupting influences of colonial culture on the East Coast. This dissertation investigates the ethnogenesis, evolution, and endurance of the Brothertown Indian community from the perspective of collaborative historical archaeology. In doing so, it aims to reassess theories of culture, identity, and discourse in the modern postcolonial world, and to incorporate archaeological data into the study of Brothertown history. In order to accomplish these goals, this dissertation analyzes historical documents, cemeteries, and settlement patterns using theories of practice and pragmatics. The results of these analyses reveal the ways in which several tribal groups joined together to form a new type of Native community and negotiate colonial politics, specifically the roles that linguistic, material culture, and spatial discourses played in these processes. Certain discourses challenged dominant schemes of social classification, obfuscating categories such as “Indian” and “White,” but also had pragmatic impacts within the Brothertown community that shaped memory processes, conceptions of personhood and identity, and overall communal structures. This study concludes that instances of ethnogenesis hinge upon insiders and outsiders continually negotiating social boundaries via words, things, and spaces. It rejects dichotomous frameworks of cultural change that classify materials and practices solely in terms of their origins for more complex considerations of the long-term, pragmatic results of such entanglements

Malaysian household income distribution: a fractal point of view

Malaysian Household Income Survey data provided by the Malaysian Department of Statistics is used to provide evidence that the upper tails of the household income distribution follows a fractal based distribution known as power-law. Inequality measures are then applied to ascertain the levels of inequality based on this distribution. In addition to that, we analyzed the data in terms of different classes of occupation, obtained power-law exponents for each class and then highlighted the inequality between these classes

Personalized Mobile System Application: A Case Study

This paper presents an overview of the components, approaches and techniques which are used to build a mobile phone- application that uses short messaging service (SMS) text messages to improve interaction, information distribution and communication of stakeholders in a university setting. The proposed application is built upon a multiple compatible mobile phone menu-based subscription management application that is also customizable.  Since SMS has the potential to fill significant connectivity and service gaps, this application can provide support for them to become more ubiquitous. Event-based approach towards context-aware personalized notification service is adopted, i.e. user will receive relevant immediate SMS to his/her mobile phone based on his/her subscription for preferred notifications. A trigger enables event management system to send out (semi-) automated personalized notification. Notification services that understand the context within which their users operate, i.e. identity, activity and time are derived based on a set of predetermined rules. This will benefit the stakeholders in terms of getting up-to-date notifications via the delivery system which implements SysMan TellMe V8.04 as the delivery protocol and SMS server

Impak kitaran sosial dalam sumbangan alumni terhadap pendapatan endowmen universiti

Pelan Strategik Pengajian Tinggi Negara (PSPTN) dirangka bagi memperkasa pendidikan tinggi negara. Antara perancangan pelan ini adalah memberikan kuasa autonomi kepada pihak universiti untuk menguruskan operasi universiti. Keadaan ini bergantung kepada kemampuan pihak universiti untuk mencapai peruntukan sasaran kementerian bagi menanggung kos operasi mengurus dan membangun universiti. Antara strategi kewangan yang difokuskan dalam pelan ini ialah meningkatkan pendapatan endowmen universiti melalui sumbangan alumni. Walau bagaimanapun, kesanggupan alumni memberikan sumbangan boleh berubah-ubah dan bergantung kepada beberapa faktor. Dalam kajian ini, lima faktor sumbangan alumni telah dianalisis iaitu pengurusan kewangan, personaliti diri, eksternal, pengurusan universiti dan jalinan universiti-komuniti. Faktor-faktor ini turut diinteraksi untuk menghasilkan indikator yang dikenali pemboleh ubah kitaran sosial. Pemboleh ubah kitaran bertujuan mengukur impak perubahan faktor-faktor terhadap nilai sumbangan. Ujian regresi diaplikasi untuk menganalisis faktor-faktor yang dikaji terhadap sumbangan alumni ini. Dapatan analisis menunjukkan bahawa pemboleh ubah kitaran sosial mempengaruhi secara signifikan terhadap pendapatan endowmen universiti antara 3 hingga 4 peratus. Implikasi kajian ini membuktikan saluran sumbangan alumni signifikan untuk diteroka oleh pihak universiti bagi menampung sebahagian defisit peruntukan yang dialami