Prediction of stocks: a new way to look at it.

While the traditional $R^{2}$ value is useful to evaluate the quality of a fit, it does not work when it comes to evaluating the predictive power of estimated financial models in finite samples. In this paper we introduce a validated $R_{V}^{2}$ value that is Taylor made for prediction. Based on data from the Danish stock market, using this measure we find that the dividend-price ratio has good predictive power for time horizons between one year and five years. We explain how the $R_{S}^{2}$ s for different time horizons could be compared, respectively, how they must not be interpreted. For our data we can conclude that the quality of prediction is almost the same for the five different time horizons. This is in contradiction to earlier studies based on the traditional $R^{2}$ value, where it has been argued that the predictive power increases with the time horizon up to a horizon of about five or six years. Furthermore, we find that while inflation and interest rate do not add to the predictive power of the dividend-price ratio then last years excess stock return does

Estimation of a semiparametric transformation model

This paper proposes consistent estimators for transformation parameters in semiparametric models. The problem is to find the optimal transformation into the space of models with a predetermined regression structure like additive or multiplicative separability. We give results for the estimation of the transformation when the rest of the model is estimated non- or semi-parametrically and fulfills some consistency conditions. We propose two methods for the estimation of the transformation parameter: maximizing a profile likelihood function or minimizing the mean squared distance from independence. First the problem of identification of such models is discussed. We then state asymptotic results for a general class of nonparametric estimators. Finally, we give some particular examples of nonparametric estimators of transformed separable models. The small sample performance is studied in several simulations.Comment: Published in at http://dx.doi.org/10.1214/009053607000000848 the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

Search for the production of a single excited b quark in the Wt final state with a single lepton in pp collisions at sqrt s = 13 TeV with the ATLAS detector

In dieser Dissertation wird eine Suche nach einem angeregten $b$ Quark, $b^*$, durchgeführt. Für diese $b^*$ wird eine anomale Kopplung an Bosonen aus dem Standard Modell vorhergesagt. Diese Kopplung führt zu der Produktion in hochenergetischen Proton-Proton Kollisionen. In der Suche zielen wir auf Ereignisse, bei denen eines der zwei $W$ Bosonen in ein Elektron oder Muon zerfällt und das andere in ein Hadronenpaar. Da es nur ein Neutrino in diesem Prozess gibt, kann das ganze Ereigniss kinematisch rekonstruiert werden. Damit ist es möglich, die Masse des $b^*$ als diskriminierende Variable zu verwenden. Als Datenquelle dienen die Daten, die der ATLAS Detektor in den Jahren 2015 und 2016 bei Proton-Proton Kollisionen mit einer Schwerpunksenergie von \sqrt s = \SI{13}{\tera\electronvolt} aufgezeichnet hat. Dabei entspricht diese Datenmenge einer integrierten Luminosität von \L_{int} = \SI{36.1}{\femto\barn^{-1}}. Da die Analyse auf hochmassige $b^*$ abziehlt, kann man davon ausgehen, dass das Hadronenpaar aus dem $W$ Zerfall in einen Jet mit großen Radius passt. Es wurde kein signifikanter Überschuss über den Untergrund gefunden. Damit können nur obere Ausschlussgrenzen bezüglich der Wirkungsquerschnitte in dem entsprechenden Zerfallskanal abgeleitet werden. Unter Annahme von einer Kopplungskonstanten von 1, sind Zerfälle von $b^*\to Wt$ bis zu einer Masse m_{b^*,\mathrm{obs}}= \SI{2.5}{\tera\electronvolt} ausgeschlossen, wobei erwartet wurde, dass die Ausschlussmasse bei m_{b^*,\mathrm{exp}}= \SI{2.4}{\tera\electronvolt} liegen würde.A search for an excited $b$ quark, $b^*$, in events containing a top quark and a $W$ boson is investigated. These $b^*$ are predicted to have some anomalous couplings to Standard Model bosons aiding the production in high energy proton-proton collisions. The search is aiming for events, where one of the two $W$ bosons decays into an electron or muon, while the other decays hadronically. With only one neutrino, the event can be kinematically fully reconstructed. This enables the use of the mass of the $b^*$ as the discriminant variable. The data source under investigation is the data taken by the ATLAS detector at the LHC accelerator in the years 2015 and 2016 at a center-of-mass energy of \sqrt s = \SI{13}{\tera\electronvolt}. The combined dataset corresponds to an integrated luminosity of \L_{int} = \SI{36.1}{\femto\barn^{-1}}. The analysis targets high mass excited $b^*$ quarks, where the products of the hadronically decaying $W$ are contained within a large-radius jet. No significant excess over the expected background is observed and upper limits on the cross-section times branching ratio and coupling limits are derived. Assuming unit coupling, $b^*$ decaying into $Wt$ are excluded up to m_{b^*,\mathrm{obs}}= \SI{2.5}{\tera\electronvolt}, with an expected exclusion limit of m_{b^*,\mathrm{exp}}= \SI{2.4}{\tera\electronvolt}

Designing a brain-based learning environment

The purpose of this project was to develop a teacher friendly guide that would help teachers not only apply brain-based strategies in the classroom, but also to see results from transforming their classrooms into brain-based learning environments