September 2014
Intermediate to advanced
236 pages
4h 17m
Japanese
Content preview from Think Bayes ―プログラマのためのベイズ統計入門
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.
172
■
14
章
階層的モデル
各粒子の検出確率が、他とは独立であると仮定すれば、
k
の分布は、パラメータが
n
と
f
の二項分布になる。
システムのパラメータが与えられれば、データの分布がわかる。したがって、順問
題（
forward problem
）
＊
1
と呼ばれるものを解くことができる。
さて、私たちは逆方向に進みたい。データが与えられて、パラメータの分布を求めた
い。これは、逆問題（
inverse problem
）と呼ばれる。そして、順問題が解けるなら、ベ
イズ手法を使って、逆問題が解ける。
14.2
シンプルに始める
r
の値がわかっているという単純な問題から始めよう。
f
の値が与えられていて、
n
を
推定するだけでよいとする。
Detector
というスイートを定義して、検出器の振る舞いをモデル化して、
n
を推定
する。
class Detector(thinkbayes.Suite):
def
__
init
__
(self, r, f, high=500, step=1):
pmf = thinkbayes.MakePoissonPmf(r, high, step=step)
thinkbayes.Suite.
__
init
__
(self, pmf, name=r)
self.r = r
self.f = f
平均放射率が、秒間
r
粒子なら、
n
の分布は、パラメータが
r
のポワソン分布である。
high
と
step
とは、
n
の上限と仮説値の間のステップサイズである。
次は、尤度関数が必要だ。
# class Detector ...
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.