Providing some basic understanding behind a regression approach to a classification problem in DQNs action values.

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This article assumes an understanding of classification and regression when it comes to deep learning and a basic understanding of Reinforcement Learning.

This article was made to address issues when it comes approaching DQNs, as it seems we are doing regression to a problem that requires classification. What is really going on? By the end of this article, I hope it will be clear…

Setup: We assume a Deep-RL example of a DQN with 4 discrete available actions, and we want to select one…

Understanding the basic concepts behind Reinforcement Learning using value-based methods

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Reinforcement Learning (RL) is a Machine Learning field which gained much attention since 2015 after Google’s Deep Mind team demonstrated self-taught DQN agents learning to walk, mastering Atari games and beating pro-human players in the game Go.

Watch DeepMind walking agents
DeepMind learning to play Breakout

RL is the science behind self-taught software agents who explore a previously unknown world and eventually excel in that world. …

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Hi everyone,

When I started playing around with neural networks, I had a lot of questions regarding the theory of neural networks, and while many things were taken for granted, I always wanted to dig into more detail when it comes to how neural networks work.

All this made me want to make an easy to follow tutorial regarding the theory behind Deep Learning and Neural Networks, that would be descriptive and clear enough for the beginners to follow, but also a good recap for people already familiar with the theory.


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There is bizarre behavior in Android when you combine a “WebView” together with “AdMob”.

The Scrolling Problem

When the AdMob finishes loading, there is a known bug where the WebView scrolls down. This can be frustrating and there are various articles on the web with questions in sites such as StackOverflow regarding this problem.

The Scrolling Solution

The only working solution so far, found in several StackOverflow answers is to block the descendants’ focusability from your layout XML using the following code at the scrollbar’s XML:


Doing the above hack will fix the scrolling problem that happens when your AdMob advert finishes loading.

However, that…

So what is AMP? How will it change our website? Is it any useful? How hard is it to implement? How important is it? Should I replace my mobile website with AMP? What is Accelerated Mobile Pages anyway?

The above are some of the many questions someone has about this new SEO trend for mobile searches. We hope that if you read through the end of this article, most of these questions will be answered.

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Visit the official site about the AMP Project and see the Google Blog AMP Announcement.

What is AMP

AMP stands for “Accelerated Mobile Pages”. It's a new standard…

A static variable is a variable that doesn’t belong to an instance of that class, but to the class itself.

Equivalently a static method belongs to the class, rather than an object instance.

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Let’s take the example of a very simple class:

public class Person(){ private static int population = 0; private String name; private String surname; public Person(String name, String surname){ population++;; this.surname=surname; } /** * A member variable that returns the specific * object's full name. */ public String getFullName(){ return name+" "+surname; } /** * A static method that returns the total * amount of person…

An Activity making a direct Intent call using AsyncTask’s onPostExecute(…) while the AsyncTask is at a separate file…

This article is describing a common pattern widely used in Android Development.

There are more cases where this technique applies, for example creating a clickListener for items in a recycler view, where we need to somehow forward click information from the Adapter class to the Activity class… so… keep reading!

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The Problem

If AsyncTask class is implemented in a file outside an “Activity”, how can we make the “intent” call from inside the activity, rather than from the AsyncTask class’s “onPostExecute” method?

In a nutshell…

Since our AsyncTask will be a separate java file, then the onPostExecute will be exist on that file, thus outside…

Ioannis Anifantakis

MSc Computer Science. — Software engineer and programming instructor. Actively involved in Android Development and Deep Learning.

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