August 2015
Intermediate to advanced
312 pages
7h 28m
Japanese
Content preview from 初めてのSpark
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.
222
11 章 MLlib を使った機械学習
3.
ベクトルの
RDD
に対して分類アルゴリズム（例えばロジスティック回帰）を呼びます。
これで、新しいデータ点を分類するために使えるモデルオブジェクトが返されます。
4.
テスト用のデータセットで
MLlib
の評価関数の
1
つを使い、モデルを評価します。
MLlib
について注意するべき重要なことの
1
つは、
MLlib
に含まれているのは、クラスタ上で
うまく動作するアルゴリズムだけである点です。古くからある機械学習のアルゴリズムの中に
は、並列プラットフォーム用に設計されていないことから
MLlib
に含まれていないものもありま
すが、一方で
MLlib
には分散ランダムフォレスト、
K
平均法、交互最小
2
乗法といった、近年研
究されたアルゴリズムがいくつか含まれています。こうした選択が行われていることで、
MLlib
は
それぞれのアルゴリズムを大規模なデータセットに対して実行する上で最適なものになっているの
です。仮に、多種類の学習モデルのトレーニングを行うための小さなデータセットを大量に持って
いるなら、例えば
Spark
の
map()
を使い、各ノード上で単一ノード用の学習ライブラリ（例えば
Weka http://www.cs.waikato.ac.nz/ml/weka/
や
SciKit-Learn http://scikit-learn.org/stable/
）
を呼ぶ方が良いかもしれません。同様に、機械学習のパイプラインでは、最適なパラメータ設定を
選択するために、小さなデータセットに対して ...
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.