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 Decision Tree Learning


Asymptotic Unbiasedness of the Permutation Importance Measure in Random Forest Models

arXiv.org Machine Learning

Variable selection in sparse regression models is an important task as applications ranging from biomedical research to econometrics have shown. Especially for higher dimensional regression problems, for which the link function between response and covariates cannot be directly detected, the selection of informative variables is challenging. Under these circumstances, the Random Forest method is a helpful tool to predict new outcomes while delivering measures for variable selection. One common approach is the usage of the permutation importance. Due to its intuitive idea and flexible usage, it is important to explore circumstances, for which the permutation importance based on Random Forest correctly indicates informative covariates. Regarding the latter, we deliver theoretical guarantees for the validity of the permutation importance measure under specific assumptions and prove its (asymptotic) unbiasedness. An extensive simulation study verifies our findings.


RoNGBa: A Robustly Optimized Natural Gradient Boosting Training Approach with Leaf Number Clipping

arXiv.org Machine Learning

Natural gradient has been recently introduced to the field of boosting to enable the generic probabilistic predication capability. Natural gradient boosting shows promising performance improvements on small datasets due to better training dynamics, but it suffers from slow training speed overhead especially for large datasets. W e present a replication study of NGBoost ( Duan et al., 2019) training that carefully examines the impacts of key hyper-parameters under the circumstance of best-first decision tree learning. W e find that with the regularization of leaf number clipping, the performance of NGBoost can be largely improved via a better choice of hyperparameters. Experiments show that our approach significantly beats the state-of-the-art performance on various kinds of datasets from the UCI Machine Learning Repository while still has up to 4.85x speed up compared with the original approach of NGBoost.


Proving Data-Poisoning Robustness in Decision Trees

arXiv.org Artificial Intelligence

Machine learning models are brittle, and small changes in the training data can result in different predictions. We study the problem of proving that a prediction is robust to data poisoning, where an attacker can inject a number of malicious elements into the training set to influence the learned model. We target decision-tree models, a popular and simple class of machine learning models that underlies many complex learning techniques. We present a sound verification technique based on abstract interpretation and implement it in a tool called Antidote. Antidote abstractly trains decision trees for an intractably large space of possible poisoned datasets. Due to the soundness of our abstraction, Antidote can produce proofs that, for a given input, the corresponding prediction would not have changed had the training set been tampered with or not. We demonstrate the effectiveness of Antidote on a number of popular datasets.


How Spotify know a lot about you using machine learning and AI.

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Spotify is one of the best music streaming industry in the market. But what excites us the most is the amazing ways it uses to enhance the user experience. We all would be familiar with "discover weekly" which is a personalized playlist unique to each user. It is using artificial intelligence and machine learning algorithms to generates the playlist. It learns through your music preferences, streaming history or how many times you listened to a particular song.


Short Term Prediction of Parking Area states Using Real Time Data and Machine Learning Techniques

arXiv.org Machine Learning

Public road authorities and private mobility service providers need information derived from the current and predicted traffic states to act upon the daily urban system and its spatial and temporal dynamics. In this research, a real-time parking area state (occupancy, in- and outflux) prediction model (up to 60 minutes ahead) has been developed using publicly available historic and real time data sources. Based on a case study in a real-life scenario in the city of Arnhem, a Neural Network-based approach outperforms a Random Forest-based one on all assessed performance measures, although the differences are small. Both are outperforming a naive seasonal random walk model. Although the performance degrades with increasing prediction horizon, the model shows a performance gain of over 150% at a prediction horizon of 60 minutes compared with the naive model. Furthermore, it is shown that predicting the in- and outflux is a far more difficult task (i.e. performance gains of 30%) which needs more training data, not based exclusively on occupancy rate. However, the performance of predicting in- and outflux is less sensitive to the prediction horizon. In addition, it is shown that real-time information of current occupancy rate is the independent variable with the highest contribution to the performance, although time, traffic flow and weather variables also deliver a significant contribution. During real-time deployment, the model performs three times better than the naive model on average. As a result, it can provide valuable information for proactive traffic management as well as mobility service providers.


A Dynamic Modelling Framework for Human Hand Gesture Task Recognition

arXiv.org Machine Learning

Gesture recognition and hand motion tracking are important tasks in advanced gesture based interaction systems. In this paper, we propose to apply a sliding windows filtering approach to sample the incoming streams of data from data gloves and a decision tree model to recognize the gestures in real time for a manual grafting operation of a vegetable seedling propagation facility. The sequence of these recognized gestures defines the tasks that are taking place, which helps to evaluate individuals' performances and to identify any bottlenecks in real time. In this work, two pairs of data gloves are utilized, which reports the location of the fingers, hands, and wrists wirelessly (i.e., via Bluetooth). To evaluate the performance of the proposed framework, a preliminary experiment was conducted in multiple lab settings of tomato grafting operations, where multiple subjects wear the data gloves while performing different tasks. Our results show an accuracy of 91% on average, in terms of gesture recognition in real time by employing our proposed framework.


Understanding Decision Trees In Machine Learning and How To Implement It In Python Using sklearn

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Decision Trees are a type of supervised learning used for classification (yes/no) and regression (continuous data) where the data is continuously split according to a certain parameter. The predicted class is derived from features of the data. The following article creates a Decision Tree from the 311 on 3.11 Project. In this project, the resolution outcome being positive or negative is what is being predicted. Agency: NYPD, Dept of Transportation, Dept of Health & Mental Hygiene, Dept of Sanitation, Dept of Housing Preservation and Development, Dept of Parks and Recreation, etc Borough: Brooklyn, Queens, Manhattan, Bronx, Staten Island Location: Longitude/Latitude, Cross Streets, Intersections Created/Closed Date Complaint Type: Heat/Hot Water, Rodent, Noise, Street Condition, Illegal Parking, Unsanitary Condition, Blocked Driveway are just a few examples.


Top 10 Machine Learning Algorithms for Beginners Machine Learning Tutorial [Data Science]

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This Machine Learning Algorithms Tutorial video by Learnaholic India will help you learn Machine Learning Tutorial, what is Machine Learning, [Data Science] various Machine Learning problems and the algorithms, key Machine Learning algorithms with simple examples. The key Machine Learning algorithms discussed in detail are Linear Regression, Logistic Regression, Decision Tree, Random Forest and KNN algorithm. Machine Learning Tutorial [Data Science] Top 10 Machine Learning Algorithms for Beginners In this Machine Learning Algorithms Tutorial video you will understand: 1) Types of Machine Learning Algorithms (00:25) 2) Supervised Learning Algorithms (00:30) 3) Unsupervised Learning Algorithms (1:59) 4) Reinforcement Learning Algorithms (3:38) 5) Top 10 Machine Learning Algorithms for Beginners (4:33) This Machine Learning Algorithms Tutorial shall teach you what machine learning is, and the various ways in which you can use machine learning to solve a problem! Towards the end, you will learn how to prepare a data-set for model creation and validation and how you can create a model using any machine learning algorithm! Hit the subscribe button above.


Adaptive Estimation of Multivariate Piecewise Polynomials and Bounded Variation Functions by Optimal Decision Trees

arXiv.org Machine Learning

Proposed by Donoho (1997), Dyadic CART is a nonparametric regression method which computes a globally optimal dyadic decision tree and fits piecewise constant functions. In this article we define and study Dyadic CART and a closely related estimator, namely Optimal Regression Tree (ORT), in the context of estimating piecewise smooth functions in general dimensions. More precisely, these optimal decision tree estimators fit piecewise polynomials of any given degree. Like Dyadic CART in two dimensions, we reason that these estimators can also be computed in polynomial time in the sample size via dynamic programming. We prove oracle inequalities for the finite sample risk of Dyadic CART and ORT which imply tight risk bounds for several function classes of interest. Firstly, they imply that the finite sample risk of ORT of order $r \geq 0$ is always bounded by $C k \frac{\log N}{N}$ ($N$ is the sample size) whenever the regression function is piecewise polynomial of degree $r$ on some reasonably regular axis aligned rectangular partition of the domain with at most $k$ rectangles. Beyond the univariate case, such guarantees are scarcely available in the literature for computationally efficient estimators. Secondly, our oracle inequalities uncover optimality and adaptivity of the Dyadic CART estimator for function spaces with bounded variation. We consider two function spaces of recent interest where multivariate total variation denoising and univariate trend filtering are the state of the art methods. We show that Dyadic CART enjoys certain advantages over these estimators while still maintaining all their known guarantees.


Single Sample Feature Importance: An Interpretable Algorithm for Low-Level Feature Analysis

arXiv.org Machine Learning

Have you ever wondered how your feature space is impacting the prediction of a specific sample in your dataset? In this paper, we introduce Single Sample Feature Importance (SSFI), which is an interpretable feature importance algorithm that allows for the identification of the most important features that contribute to the prediction of a single sample. When a dataset can be learned by a Random Forest classifier or regressor, SSFI shows how the Random Forest's prediction path can be utilized for low-level feature importance calculation. SSFI results in a relative ranking of features, highlighting those with the greatest impact on a data point's prediction. We demonstrate these results both numerically and visually on four different datasets.