Udacity 59 views Show Developer Workflow - Duration: 2:09.

Google has announced that it is now rolling out better filtering systems to counter fraudulent app rankings on the Play Store. The company says that these are violating the Google Play Developer Policy and will bring harm to the Android community. "From time to time, we observe instances of developers attempting to manipulate the placement of their apps through illegitimate means like fraudulent installs, fake reviews, and incentivized ratings," Google said on the Android Developers Blog. "Today we are rolling out improved detection and filtering systems to combat such manipulation attempts." Apps of developers who keep on using these methods may also be taken down from the Play Store completely.

This post is a summary of 3 different posts about outlier detection methods. One of the challenges in data analysis in general and predictive modeling in particular is dealing with outliers. There are many modeling techniques which are resistant to outliers or reduce the impact of them, but still detecting outliers and understanding them can lead to interesting findings. We generally define outliers as samples that are exceptionally far from the mainstream of data.There is no rigid mathematical definition of what constitutes an outlier; determining whether or not an observation is an outlier is ultimately a subjective exercise. There are several approaches for detecting Outliers.

This is a guest repost by Jacob Joseph from CleverTap. Why would you want to convert a numerical variable into categorical one? Depending on the situation, it can lead to a better interpretation of the numerical variable, quick segmentation or just an additional feature for building your predictive model by creating bins for the numerical variable. Binning is a popular feature engineering technique. Suppose your hypothesis is that the age of a customer is correlated with their tendency to interact with a mobile app.

In this work we establish and investigate connections between causes for query answers in databases, database repairs wrt. denial constraints, and consistency-based diagnosis. The first two are relatively new research areas in databases, and the third one is an established subject in knowledge representation. We show how to obtain database repairs from causes, and the other way around. Causality problems are formulated as diagnosis problems, and the diagnoses provide causes and their responsibilities. The vast body of research on database repairs can be applied to the newer problems of computing actual causes for query answers and their responsibilities. These connections, which are interesting per se, allow us, after a transition -inspired by consistency-based diagnosis- to computational problems on hitting sets and vertex covers in hypergraphs, to obtain several new algorithmic and complexity results for database causality.

Decision tree is a graph to represent choices and their results in form of a tree. The nodes in the graph represent an event or choice and the edges of the graph represent the decision rules or conditions. It is mostly used in Machine Learning and Data Mining applications using R. Examples of use of decision tress is predicting an email as spam or not spam, predicting of a tumor is cancerous or predicting a loan as a good or bad credit risk based on the factors in each of these. Generally, a model is created with observed data also called training data. Then a set of validation data is used to verify and improve the model.

Image: Doctors were significantly better at diagnosing conditions correctly when compared to a computer algorithms, an American research trial found. Doctors "vastly outperformed" computer algorithms when it comes to giving a correct diagnosis, according to an American research trial. In the investigation, 234 physicians correctly diagnosed patients 72% of the time, in comparison to the symptom checker app, Human Dx, which only managed to score 34%. Published earlier this month in'JAMA Internal Medicine', the study stated that it is thought to be the first direct comparison of diagnostic accuracy. Human Dx, is a web and app based platform on which clinicians can produce different outcomes for clinical case studies.

Hidden Decision Trees is a statistical and data mining methodology (just like logistic regression, SVM, neural networks or decision trees) to handle problems with large amounts of data, non-linearities and strongly correlated dependent variables. The technique is easy to implement in any programming language. It is more robust than decision trees or logistic regression, and help detect natural final nodes. Implementations typically rely heavily on large, granular hash tables. No decision tree is actually built (thus the name hidden decision trees), but the final output of an hidden decision tree procedure consists of a few hundred nodes from multiple non-overlapping small decision trees.

Welcome back for another edition of Under the Decision Tree. This week we had The Data Science Conference in Seattle and interesting articles that include teaching AI to be sarcastic, predictions of what AI will look like in 2030, and much more. Please send any suggestions to: Decision Tree We would love to hear from you.

Welcome back for another edition of Under the Decision Tree. This week we had everything from machine learning being applied to cucumber farming, to major tech companies joining up to tackle the ethics of machine learning. Please send any suggestions to: Decision Tree We would love to hear from you.