Oracle JET works with any kind of REST service, such service could be the one coming from TensorFlow (read more in my previous post -- TensorFlow Linear Regression Model Access with Custom REST API using Flask). There is option to define training steps (or data points) and learning rate. As outcome we get W and b values for linear equation y Wx b. After training is executed (so called machine learning process) -- W and b parameters are identified, this allows to predict y value for any x. More about this in my next post, today will focus on JET.

We propose an efficient algorithm for approximate computation of the profile maximum likelihood (PML), a variant of maximum likelihood maximizing the probability of observing a sufficient statistic rather than the empirical sample. The PML has appealing theoretical properties, but is difficult to compute exactly. Inspired by observations gleaned from exactly solvable cases, we look for an approximate PML solution, which, intuitively, clumps comparably frequent symbols into one symbol. This amounts to lower-bounding a certain matrix permanent by summing over a subgroup of the symmetric group rather than the whole group during the computation. We extensively experiment with the approximate solution, and find the empirical performance of our approach is competitive and sometimes significantly better than state-of-the-art performance for various estimation problems.

Two-dimensional embeddings remain the dominant approach to visualize high dimensional data. The choice of embeddings ranges from highly non-linear ones, which can capture complex relationships but are difficult to interpret quantitatively, to axis-aligned projections, which are easy to interpret but are limited to bivariate relationships. Linear project can be considered as a compromise between complexity and interpretability, as they allow explicit axes labels, yet provide significantly more degrees of freedom compared to axis-aligned projections. Nevertheless, interpreting the axes directions, which are linear combinations often with many non-trivial components, remains difficult. To address this problem we introduce a structure aware decomposition of (multiple) linear projections into sparse sets of axis aligned projections, which jointly capture all information of the original linear ones. In particular, we use tools from Dempster-Shafer theory to formally define how relevant a given axis aligned project is to explain the neighborhood relations displayed in some linear projection. Furthermore, we introduce a new approach to discover a diverse set of high quality linear projections and show that in practice the information of $k$ linear projections is often jointly encoded in $\sim k$ axis aligned plots. We have integrated these ideas into an interactive visualization system that allows users to jointly browse both linear projections and their axis aligned representatives. Using a number of case studies we show how the resulting plots lead to more intuitive visualizations and new insight.

The randomized-feature approach has been successfully employed in large-scale kernel approximation and supervised learning. The distribution from which the random features are drawn impacts the number of features required to efficiently perform a learning task. Recently, it has been shown that employing data-dependent randomization improves the performance in terms of the required number of random features. In this paper, we are concerned with the randomized-feature approach in supervised learning for good generalizability. We propose the Energy-based Exploration of Random Features (EERF) algorithm based on a data-dependent score function that explores the set of possible features and exploits the promising regions. We prove that the proposed score function with high probability recovers the spectrum of the best fit within the model class. Our empirical results on several benchmark datasets further verify that our method requires smaller number of random features to achieve a certain generalization error compared to the state-of-the-art while introducing negligible pre-processing overhead. EERF can be implemented in a few lines of code and requires no additional tuning parameters.

Any-gram kernels are a flexible and efficient way to employ bag-of-n-gram features when learning from textual data. They are also compatible with the use of word embeddings so that word similarities can be accounted for. While the original any-gram kernels are implemented on top of tree kernels, we propose a new approach which is independent of tree kernels and is more efficient. We also propose a more effective way to make use of word embeddings than the original any-gram formulation. When applied to the task of sentiment classification, our new formulation achieves significantly better performance.

Parametric statistical inference often begins with the choice of a model class which is used to describe an unknown datagenerating process. In system identification and sequential data analysis, we obtain a sequence of dependent samples from this process. A classical problem has been to assess whether the unknown process is contained in the proposed model class, usually relying on large-sample results (White, 1982). In many real-world applications, however, we only have a limited data record and we expect the model class to be misspecified in some respect. A more relevant question would then be: how consistent is the model class with the observed data? A classical means of assessing a model is through its residuals or prediction errors. E.g. for linear dynamic models, one can check whether their prediction errors constitute a white noise process, cf.

In this paper we develop a method for learning nonlinear systems with multiple outputs and inputs. We begin by modelling the errors of a nominal predictor of the system using a latent variable framework. Then using the maximum likelihood principle we derive a criterion for learning the model. The resulting optimization problem is tackled using a majorization-minimization approach. Finally, we develop a convex majorization technique and show that it enables a recursive identification method. The method learns parsimonious predictive models and is tested on both synthetic and real nonlinear systems.

Optimization results are one method for understanding neural computation from Nature's perspective and for defining the physical limits on neuron-like engineering. Earlier work looks at individual properties or performance criteria and occasionally a combination of two, such as energy and information. Here we make use of Jaynes' maximum entropy method and combine a larger set of constraints, possibly dimensionally distinct, each expressible as an expectation. The method identifies a likelihood-function and a sufficient statistic arising from each such optimization. This likelihood is a first-hitting time distribution in the exponential class. Particular constraint sets are identified that, from an optimal inference perspective, justify earlier neurocomputational models. Interactions between constraints, mediated through the inferred likelihood, restrict constraint-set parameterizations, e.g., the energy-budget limits estimation performance which, in turn, matches an axonal communication constraint. Such linkages are, for biologists, experimental predictions of the method. In addition to the related likelihood, at least one type of constraint set implies marginal distributions, and in this case, a Shannon bits/joule statement arises.

Employee turnover refers to the percentage of workers who leave an organization and are replaced by new employees. It is very costly for organizations, where costs include but not limited to: separation, vacancy, recruitment, training and replacement. On average, organizations invest between four weeks and three months training new employees. This investment would be a loss for the company if the new employee decided to leave the first year. Furthermore, organizations such as consulting firms would suffer from deterioration in customer satisfaction due to regular changes in Account Reps and/or consultants that would lead to loss of businesses with clients.

To avoid an over-fitting problem (the trained model fits too well with the training data and is not generalized enough), the regularization technique is used to shrink the magnitude of Ɵi. This is done by adding a penalty (a function of the sum of Ɵi) into the cost function. In L2 regularization (also known as Ridge regression), Ɵi2 will be added to the cost function. In L1 regularization (also known as Lasso regression), Ɵi will be added to the cost function. Both L1, L2 will shrink the magnitude of Ɵi.