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Selection of subsets of variables in linear regression PDF Print E-mail
Written by Agnar Höskuldsson, DTU   
Selection of variables in linear regression is one of the most studied subjects in theoretical statistics. In applied sciences there is also considerable interest in the topic. The popular program packages like SAS, SPSS, BMDP and others have advanced programs to select variables that should be used in the modeling work. Furthermore, advanced procedures using 'Backwards, Forward, Stepwise, Jackknife and other criteria' have been developed that assist the user in finding the variables. Here some aspects of the area are discussed. A short review of the CovProc methods is presented. One type of the methods is presented and the results illustrated by numerical examples.
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Editorial flash
Svante Wold's New Year Editorial 2005
Another year has passed too quickly, and we now read January 2005 on our calendars. In 2004, good things happened and terrible, happy and sad, as usual. However, chemometrics does well, spreading deeper into biology where the data sets are larger than ever with thousands of variables in, among others, gene arrays, LC-MS profiles, and NIR and IR microscopy.
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Chemometrics’ Epistemology in Systems Biology

10 years of Systems biology research – current knowledge and future expectations

May 9-11 2011, Skanör-Falsterbo, Öresund, Sweden

Systems biology has now matured and includes advanced modelling of biological systems.The condensation of divergent scientific disciplines (clinicians, biologists, mathematicians, statisticians, physicists, chemists, etc.) has forced us into a new way of working and thinking – Systems biology. This provides further challenges how to create meaningful data, extract information and ultimately gain new knowledge.

Download flyer (2010-06-10)

The focus of our conference theme, Chemometrics’ Epistemology in Systems biology will be on the scientific process, from data generation to quality of gained knowledge and its presentation to a scientific audience. Epistemology means theory of knowledge and addresses the questions: What is knowledge? How is knowledge acquired? What do systems biologists know? How do we know what we know? How knowledge convince fellow scientists? These issues will be given ample time at this EUCHEM conference, which will be limited to maximum 70 participants. Each half day will include two one-hour speeches of the same topic from two speakers representing differing point of views. The suggested format will allow plenty of time for informal discussions and networking. Further, poster presenters will be given the opportunity to give a five minutes oral presentation. This gives an opportunity also for PhD students and young researchers to contribute to the symposium.

Confirmed speakers:
Prof. Jonas Bergqvist, Dep. Analytical Chemistry, Uppsala University, Sweden
Dr. Mats Sundgren, AstraZeneca R&D Mölndal, Sweden
Dr. Nicholas Waters, CEO Neurosearch Sweden
Scientific board:
Prof. Torbjörn Lundstedt, Uppsala University & AcurePharma AB, Sweden
Dr. Mats Sundgren, AstraZeneca R&D Mölndal, Sweden
Prof. Mark Stitt, Max Planck Institute of Molecular Plant Physiology, Germany

Organization committee:
Johan Trygg (Umeå University, Umeå, Sweden)
Jenny Forshed (Karolinska Institute, Stockholm, Sweden)
Johan Gottfries (Gottfries Medicinal, Gothenburg, Sweden)
Ing-Marie Olsson (Umetrics AB, Malmö, Sweden)

 

 

 

 

 

 

 

 

 

 

 

 
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The design of a training set intended for QSAR according to the principles of SMD, makes it possible to explore - in a systematic way - the structure-activity relationships within the data-set in question. By interrogating the resulting QSAR model it is then possible to extract clues of how to modify the chemical properties of the compounds in order to possibly enhance their biological activity profile.
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