October 2014
Intermediate to advanced
288 pages
6h 27m
Japanese
Content preview from 実践 機械学習システム
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
7.3
P
が
N
より大きい場合
153
7.3.3
レーティング予測とレコメンド
これまでにインターネットで何か購入したことがある人ならば、推薦システムを見たことがあると思
います。たとえば、Amazonの「この商品を買った人はこんな商品も買っています」などがそれにあた
ります。そのようなテーマは、次章の「バスケット分析」で詳しく扱うことにします。また、他の例と
しては、映画などの商品でお気に入りを予測するようなサービスがあります。
映画 のお気に入りを予 測するという問 題は、「Netflix Challenge」として有 名です。Netflix
Challengeとは、100万ドルの賞金が賭けられた機械学習コンテストであり、Netfilxにより運営が行
われました。Netflix
―
アメリカでは有名ですが、サービスが利用できない国も多くあります
―
は
オンラインでの映画レンタルや映像ストリーミングを行う会社です。当初はD
VDを郵送するシステム
でしたが、最近ではオンラインで映像をストリーミングするシステムに力を入れています。Netflixは
当初から、ユーザごとに映画を推薦する機能が特徴でした。具体的には、ユーザはこれまでに見た映
画を5 段階で評価することができ、全ユーザの映画評価を基にして、おすすめの映画をユーザに合わ
せて推薦します。このモデルでは、ユーザがこれまでどの映画を見たことがあるかという情報だけで
なく、見てきた映画に対してどのように感じたか、という感情的な情報も得ることができます（もち
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.