kNN by Julia from scratch

Abstract

On this article, I'll write naive kNN algorithm with Julia. Recently, I started to use Julia and need to practice. kNN is relatively simple algorithm and nice for practice. So, here, I'll write simple kNN with Julia.

Get started with golearn: Machine Learning with Go

Overview

On this article, I’ll try golearn package on Golang.
These days, typical environment sets for data science and machine learning are Python, R, R-studio and Jupyter, although it depends on the purposes and phases. When I personally do something, I always use Python and Jupyter. But of course other programming languages have machine learning libraries and those are sometimes used.
Here, I’ll try golearn package, which is the package for machine learning.
This is the official page.

• GoLearn

As a first step, through kNN algorithms, I’ll follow the basic step of that.

Simple guide to kNN

Personally, I like kNN algorithm much. Because kNN, k nearest neighbors, uses simple distance method to classify data, you can use that in the combination with other algorithms. It can also be one of the first step to study machine learning algorithms because of the simplicity.

On the following articles, I wrote about kNN. But although I myself don’t know the reason, I’ve never touched the simplest usage of kNN, meaning how to use kNN of sklearn’s library.

• kNN by Golang from scratch
• How to write kNN by TensorFlow
• Speed up naive kNN by the concept of kmeans
• CNN + KNN model accuracy

How to write kNN by TensorFlow

Overview

How do we write machine learning algorithms with TensorFlow?
I usually use TensorFlow only when I write neural networks. But actually TensorFlow is not only for that. It also can be used to write other machine leaning algorithms.
On this article, I tried to roughly write kNN algorithm by TensorFlow.

Speed up naive kNN by the concept of kmeans

Overview

About prediction, kNN(k nearest neighbors) is very slow algorithm, because it calculates all the distances between predict target and training data point on the predict phase.
By adding some process, I tried to make the naive kNN speed up and checked how much the time and accuracy changes.

kNN by Golang from scratch

Overview

I wrote kNN(k nearest neighbors), one of the machine learning algorithms, by Go.
Go has some machine learning packages but it is hard to find the information of how to write machine learning algorithms by Go. So I stepwise introduce how to. This time kNN.
This article is to understand how the algorithm. So I don’t use some elements to improve the accuracy if it disturbs the understanding essential points.

CNN + KNN model accuracy

Overview

On the contest site like Kaggle, we can see many trials and good scores by the combination of some methods.
For example, you can get scores by logistic regression and lasso regression. You can make xgboost model by using those scores.
This time, about cifar-10, I make CNN model. And by using the score, I check KNN scores.