July 2014
Beginner to intermediate
456 pages
11h 26m
Japanese
Content preview from 戦略的データサイエンス入門 ―ビジネスに活かすコンセプトとテクニック
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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.
155
155
6.2 最近傍を使った推論
2
人の間の距離は約
19
となりました。この距離はただの数値で、単位もありませんし、意
味のある解釈もできません。この数値が本当に役に立つのは、ある
2
つのインスタンス間の
類似度と別の
2
つのインスタンス間の類似度を比較する時だけです。類似度を比較すること
が極めて有効だということはこれからわかってくるでしょう。
6.2
最近傍を使った推論
さて距離を測る方法がわかったところで、それをいろいろなデータ分析のタスクで使っ
てみたいと思うことでしょう。この章の冒頭に出てきた例を思い出してみると、この尺度
を使って顧客の企業に最も近い企業を探したり、小売店の優良顧客に最も似たオンラインの
顧客を探したりということができるはずです。そうした顧客を一度見つけてしまえば、ビ
ジネス環境に合わせて適切なアクションを自在にとることができます。企業顧客に対して
IBM
は販売部隊を投入するでしょうし、オンライン広告主は広告のターゲッティングを行
うでしょう。このようにある対象に対して最も類似しているインスタンス群のことを最近傍
（
nearest neighbors
）と呼びます。
6.2.1
例：ウィスキーを分析する
ここからは新しい例を使ってお話をしましょう。私たち著者の
1
人（フォスター）はシ
ングルモルトのスコッチウィスキーがお気に入りです。みなさんも一度や二度飲んだことが
あれば、数百種類にものぼるシングルモルトにはさまざまな違いがあることをご存知でしょ
う。フォスターは本当に気に入ったシングルモルトを見つけると、他にも似たものを探した ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
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.