@article{RaetschSchoelkopfSmolaetal.2000,
  author    = {R{\"a}tsch, Gunnar and Sch{\"o}lkopf, B. and Smola, Alexander J. and M{\"u}ller, Klaus-Robert and Mika, Sebastian},
  title     = {V-Arc : ensemble learning in the preence of outliers},
  year      = {2000},
  language  = {en}
}
@article{ParraSpenceSajdaetal.2000,
  author    = {Parra, L. and Spence, C. and Sajda, P. and Ziehe, Andreas and M{\"u}ller, Klaus-Robert},
  title     = {Unmixing hyperspectral data},
  year      = {2000},
  language  = {en}
}
@article{SugiyamaKawanabeMueller2004,
  author    = {Sugiyama, Masashi and Kawanabe, Motoaki and M{\"u}ller, Klaus-Robert},
  title     = {Trading variance reduction with unbiasedness : the regularized subspace information criterion for robust model selection in kernel regression},
  issn      = {0899-7667},
  year      = {2004},
  abstract  = {A well-known result by Stein (1956) shows that in particular situations, biased estimators can yield better parameter estimates than their generally preferred unbiased counterparts. This letter follows the same spirit, as we will stabilize the unbiased generalization error estimates by regularization and finally obtain more robust model selection criteria for learning. We trade a small bias against a larger variance reduction, which has the beneficial effect of being more precise on a single training set. We focus on the subspace information criterion (SIC), which is an unbiased estimator of the expected generalization error measured by the reproducing kernel Hilbert space norm. SIC can be applied to the kernel regression, and it was shown in earlier experiments that a small regularization of SIC has a stabilization effect. However, it remained open how to appropriately determine the degree of regularization in SIC. In this article, we derive an unbiased estimator of the expected squared error, between SIC and the expected generalization error and propose determining the degree of regularization of SIC such that the estimator of the expected squared error is minimized. Computer simulations with artificial and real data sets illustrate that the proposed method works effectively for improving the precision of SIC, especially in the high-noise-level cases. We furthermore compare the proposed method to the original SIC, the cross-validation, and an empirical Bayesian method in ridge parameter selection, with good results},
  language  = {en}
}
@article{ShenoyKrauledatBlankertzetal.2006,
  author    = {Shenoy, Pradeep and Krauledat, Matthias and Blankertz, Benjamin and Rao, Rajesh P. N. and M{\"u}ller, Klaus-Robert},
  title     = {Towards adaptive classification for BCI},
  doi       = {10.1088/1741-2560/3/1/R02},
  year      = {2006},
  abstract  = {Non-stationarities are ubiquitous in EEG signals. They are especially apparent in the use of EEG-based brain- computer interfaces (BCIs): (a) in the differences between the initial calibration measurement and the online operation of a BCI, or (b) caused by changes in the subject's brain processes during an experiment (e.g. due to fatigue, change of task involvement, etc). In this paper, we quantify for the first time such systematic evidence of statistical differences in data recorded during offline and online sessions. Furthermore, we propose novel techniques of investigating and visualizing data distributions, which are particularly useful for the analysis of (non-) stationarities. Our study shows that the brain signals used for control can change substantially from the offline calibration sessions to online control, and also within a single session. In addition to this general characterization of the signals, we propose several adaptive classification schemes and study their performance on data recorded during online experiments. An encouraging result of our study is that surprisingly simple adaptive methods in combination with an offline feature selection scheme can significantly increase BCI performance},
  language  = {en}
}
@article{BlankertzDornhegeKrauledatetal.2006,
  author    = {Blankertz, Benjamin and Dornhege, Guido and Krauledat, Matthias and M{\"u}ller, Klaus-Robert and Kunzmann, Volker and Losch, Florian and Curio, Gabriel},
  title     = {The Berlin brain-computer interface : EEG-based communication without subject training},
  issn      = {1534-4320},
  doi       = {10.1109/Tnsre.2006.875557},
  year      = {2006},
  abstract  = {The Berlin Brain-Computer Interface (BBCI) project develops a noninvasive BCI system whose key features are 1) the use of well-established motor competences as control paradigms, 2) high-dimensional features from 128-channel electroencephalogram (EEG), and 3) advanced machine learning techniques. As reported earlier, our experiments demonstrate that very high information transfer rates can be achieved using the readiness potential (RP) when predicting the laterality of upcoming left-versus right-hand movements in healthy subjects. A more recent study showed that the RP similarily accompanies phantom movements in arm amputees, but the signal strength decreases with longer loss of the limb. In a complementary approach, oscillatory features are used to discriminate imagined movements (left hand versus right hand versus foot). In a recent feedback study with six healthy subjects with no or very little experience with BCI control, three subjects achieved an information transfer rate above 35 bits per minute (bpm), and further two subjects above 24 and 15 bpm, while one subject could not achieve any BCI control. These results are encouraging for an EEG-based BCI system in untrained subjects that is independent of peripheral nervous system activity and does not rely on evoked potentials even when compared to results with very well-trained subjects operating other BCI systems},
  language  = {en}
}
@article{BlankertzMuellerKrusienskietal.2006,
  author    = {Blankertz, Benjamin and M{\"u}ller, Klaus-Robert and Krusienski, Dean and Schalk, Gerwin and Wolpaw, Jonathan R. and Schl{\"o}gl, Alois and Pfurtscheller, Gert and Millan, Jos{\´e} del R. and Schr{\"o}der, Michael and Birbaumer, Niels},
  title     = {The BCI competition III : validating alternative approaches to actual BCI problems},
  issn      = {1534-4320},
  doi       = {10.1109/Tnsre.2006.875642},
  year      = {2006},
  abstract  = {A brain-computer interface (BCI) is a system that allows its users to control external devices with brain activity. Although the proof-of-concept was given decades ago, the reliable translation of user intent into device control commands is still a major challenge. Success requires the effective interaction of two adaptive controllers: the user's brain, which produces brain activity that encodes intent, and the BCI system, which translates that activity into device control commands. In order to facilitate this interaction, many laboratories are exploring a variety of signal analysis techniques to improve the adaptation of the BCI system to the user. In the literature, many machine learning and pattern classification algorithms have been reported to give impressive results when applied to BCI data in offline analyses. However, it is more difficult to evaluate their relative value for actual online use. BCI data competitions have been organized to provide objective formal evaluations of alternative methods. Prompted by the great interest in the first two BCI Competitions, we organized the third BCI Competition to address several of the most difficult and important analysis problems in BCI research. The paper describes the data sets that were provided to the competitors and gives an overview of the results.},
  language  = {en}
}
@article{BlankertzMuellerCurioetal.2004,
  author    = {Blankertz, Benjamin and M{\"u}ller, Klaus-Robert and Curio, Gabriel and Vaughan, Theresa M. and Schalk, Gerwin and Wolpaw, Jonathan R. and Schlogl, Alois and Neuper, Christa and Pfurtscheller, Gert and Hinterberger, Thilo and Schroder, Michael and Birbaumer, Niels},
  title     = {The BCI competition 2003 : Progress and perspectives in detection and discrimination of EEG single trials},
  issn      = {0018-9294},
  year      = {2004},
  abstract  = {Interest in developing a new method of man-to-machine communication-a brain-computer interface (BCI)-has grown steadily over the past few decades. BCIs create a new communication channel between the brain and an output device by bypassing conventional motor output pathways of nerves and muscles. These systems use signals recorded from the scalp, the surface of the cortex, or from inside the brain to enable users to control a variety of applications including simple word-processing software and orthotics. BCI technology could therefore provide a new communication and control option for individuals who cannot otherwise express their wishes to the outside world. Signal processing and classification methods are essential tools in the development of improved BCI technology. We organized the BCI Competition 2003 to evaluate the current state of the art of these tools. Four laboratories well versed in EEG-based BCI research provided six data sets in a documented format. We made these data sets (i.e., labeled training sets and unlabeled test sets) and their descriptions available on the Internet. The goal in the competition was to maximize the performance measure for the test labels. Researchers worldwide tested their algorithms and competed for the best classification results. This paper describes the six data sets and the results and function of the most successful algorithms},
  language  = {en}
}
@book{RaetschSchoelkopfMikaetal.2000,
  author    = {R{\"a}tsch, Gunnar and Sch{\"o}lkopf, B. and Mika, Sebastian and M{\"u}ller, Klaus-Robert},
  title     = {SVM and boosting : one class},
  series = {GMD-Report},
  volume    = {119},
  journal   = {GMD-Report},
  publisher = {GMD-Forschungszentrum Informationstechnik},
  address   = {Sankt Augustin},
  pages     = {36 S.},
  year      = {2000},
  language  = {en}
}
@book{TsudaSugiyamaMueller2000,
  author    = {Tsuda, Koji and Sugiyama, Masashi and M{\"u}ller, Klaus-Robert},
  title     = {Subspace information criterion for non-quadratice regularizers : model selection for sparse regressors},
  series = {GMD-Report},
  volume    = {120},
  journal   = {GMD-Report},
  publisher = {GMD-Forschungszentrum Informationstechnik},
  address   = {Sankt Augustin},
  pages     = {36 S.},
  year      = {2000},
  language  = {en}
}
@article{LemmBlankertzCurioetal.2005,
  author    = {Lemm, Steven and Blankertz, Benjamin and Curio, Gabriel and M{\"u}ller, Klaus-Robert},
  title     = {Spatio-spectral filters for improving the classification of single trial EEG},
  issn      = {0018-9294},
  year      = {2005},
  abstract  = {Data recorded in electroencephalogram (EEG)-based brain-computer interface experiments is generally very noisy, non-stationary, and contaminated with artifacts that can deteriorate discrimination/classification methods. In this paper, we extend the common spatial pattern (CSP) algorithm with the aim to alleviate these adverse effects. In particular, we suggest an extension of CSP to the state space, which utilizes the method of time delay embedding. As we will show, this allows for individually tuned frequency filters at each electrode position and, thus, yields an improved and more robust machine learning procedure. The advantages of the proposed method over the original CSP method are verified in terms of an improved information transfer rate (bits per trial) on a set of EEG-recordings from experiments of imagined limb movements},
  language  = {en}
}