x**g
发帖数: 807 | 1 factor analysis 是给Variable“归类”，
Mixture Models是给人“归类”。 |
|
w****a
发帖数: 155 | 2 Bias-variance 和Bayes factor 都可以用来比较不同的model, 但他们之间有何区别呢
？谢谢。 |
|
S******y
发帖数: 1123 | 3 Is there Non-negative Matrix Factorization implemented in R?
Thanks. |
|
l*****n
发帖数: 72 | 4 We all know correlation will indicate the similarities between two sequences
.
Here we are using the standard Pearson's product-moment coefficient.
For example, if you have
a=[1 -1 -1 -1 -1 ]
b=[1 -1 -1 -1 -1 ]
then obviously, correlation between factor a and b is
corr(a, b)=1;
Let us change b a little bit to c
c=[-1 1 -1 -1 -1 ]
then corr(a, c)=-0.25 < 0, i.e., negative value.
Now, let us attach many many -1 at the end of a and c, i.e.,
a=[1 -1 -1 -1 -1 -1 -1 -1 ...... -1 ]
c=[-1 1 -1 -1 -1 -1 |
|
m**c
发帖数: 88 | 5 R 中哪个package 能够计算 Bayes Factor？
能不能推荐个？
网上没搜到啊？ 要自己写代码吗？ |
|
s*******r
发帖数: 181 | 6 先CORRELATION, 去掉CORRELATION 接近1的；但是一定要有些CORRELATION, 不然做
FACTOR ANALYSIS 也没什么意义 （如果 TOTALLY INDEPENDENT). |
|
l***a
发帖数: 12410 | 7 then factor analysis? no need to do multicolinearity analysis? |
|
p********a
发帖数: 5352 | 8 ☆─────────────────────────────────────☆
lyndern (随便) 于 (Wed Mar 3 17:43:44 2010, 美东) 提到:
We all know correlation will indicate the similarities between two sequences
.
Here we are using the standard Pearson's product-moment coefficient.
For example, if you have
a=[1 -1 -1 -1 -1 ]
b=[1 -1 -1 -1 -1 ]
then obviously, correlation between factor a and b is
corr(a, b)=1;
Let us change b a little bit to c
c=[-1 1 -1 -1 -1 ]
then corr(a, c)=-0.25 < 0, i.e., negative value.
Now, let us attach many |
|
p*****o
发帖数: 543 | 9 PROC FACTOR DATA = A METHOD = PRIN MINEIGEN = 1 SCREE
ROTATE = VARIMAX;
VAR A - D;
RUN;
我的疑问是，既然METHOD是PRIN，就是应该做PCA吧，那不就是应该已经是要使得各个
COMPONENT正交，并且最大化VARIANCE了么，那ROTATE = VARIMAX这个选项还能起到作
用么？ |
|
g******h
发帖数: 266 | 10 我用下面的简单程序得到了 communality 和 covariance matrix S of the same data
。 然后想算 Specific variances. 根据定义应该是 Specific variance=Sii-
communality. 但是不知道为什么有的Sii的值比communality小。这是怎么回事啊？ 高
人指点一下吧。
程序：
proc factor data=test method=principal covariance;
run;
proc corr data=test cov;
var X1-X7;
run;
My summarized output values:
Variable Factor1_loading Communalities Sii Spedific_Variances=Sii-
communality
m100 0.67766 0.45921690 0.1553157 ??? How can it be
negative???
m200 0 |
|
g******h
发帖数: 266 | 11 I used a simple program to calculate the communality and covariance matrix S
. And use the diagonal element of S, Sii-communality to get specific
variances. But sometimes the Sii
wrong for any reason?
Code:
proc factor data=test method=principal covariance;
run;
proc corr data=test cov;
var m100 m200 m400 m800 m1500 m3000 marathon;
run;
output for communality:
Variable Communality Weight
|
|
S********a
发帖数: 359 | 12 有好多变量，这些变量间有correlation, 要做variable reduction,
SAS 是用proc factor吧，谁能给个教程/例子？
大包子答谢！！！ |
|
S********a
发帖数: 359 | 13 书名：an easy guide to factor analysis by paul kline
谢谢！！ |
|
h*********t
发帖数: 147 | 14 是的。
但是和其他random factor有不同。 |
|
d******1
发帖数: 1389 | 15 factor analysis 能写出一本书？
我怎么感觉就是一章的内容呢。lz需要很详细的介绍吗？如果只需要一些怎么用的话，
wiki？ |
|
w******e
发帖数: 142 | 16 不知道"principle component analysis" by Jolliffe对你有帮助没有，这个虽然只是
factor analysis中的一种，但是这本书还是写得比较清晰明了的。不过他不是针对
sas写得。呵呵 |
|
x*****n
发帖数: 5 | 17 推荐《A Step-by-Step Approach to Using the SAS System for Factor Analysis
and Structural Equation Modeling》，读了前面三章即可。 |
|
p********1
发帖数: 1011 | 18 是不是在一堆variables里先找几个靠谱的，扔进logistic regression里试试。
然后再加进新的variables来试。但此时，看哪个参数知道这个新加进的variable应该
保留呢？ 换句话，看哪个参数知道model提高了？
还有别的方法找risk factors嘛？ |
|
i*********e
发帖数: 783 | 19 I am using SPSS to do a probit regression.
I don't know the meaning of factor and covariant.Who can tell me?Thanks! |
|
a******1
发帖数: 1031 | 20 后验分布比等于bayes factor乘以先验分布比。 |
|
G******2
发帖数: 579 | 21 【 以下文字转载自 Quant 讨论区 】
发信人: Gigi2012 (Gigi), 信区: Quant
标 题: Re: 请问multi variate linear regression 选择risk factor 问题 (
发信站: BBS 未名空间站 (Fri Apr 10 01:32:27 2015, 美东)
他们没有report p value 和t statistics .我还在想是我不懂的原因，一般来说我先
看p value. 不过我可以要求report
R square 看起来是model 的。
给我的sad code 打不丶开。我家电脑没有sas.
说是用的Bayesian schawz criteria selection. 跟我平常用的stepwise 和backwards
selection 不一样。不懂呀。
最小的SBC 和最大的RSQ的variable 被淘汰了，说intuitive judgement 不make
sense 是个dummy variable
用了两个variable 说 SBC 最小值，然后rsq 也最大。然后multivara... 阅读全帖 |
|
G******2
发帖数: 579 | 22 发信人: Gigi2012 (Gigi), 信区: Quant
标 题: Re: 请问multi variate linear regression 选择risk factor 问题 (
发信站: BBS 未名空间站 (Fri Apr 10 01:50:02 2015, 美东)
继续问，怎么要求report 有无colineality 。我觉得这些tested variable 长得都太
相似了。 |
|
h******e
发帖数: 1811 | 23 Only primary care/ortho? If they keep cutting the pay, only the patients
will suffer, because more and more docs are just going to drop their
medicare/medicaid patients. There is already a primary care physician
shortage, this trend will sure make the shortage even worse. Doctor fees
might be a factor, but I am so sorry to see the current administration lose
sight of the big picture. |
|
f*****i
发帖数: 3558 | 24 以前读书的时候，做project，老板说过一个PI factor。就是你计划用多少时间做完，
但是事实上通常是那个时间乘上PI才做完。。。我现在觉得这个在DIY remodeling上好
像也适用呀。。。
刚过去的周末，和别人一起做一个300+sqft family room的baseboard and crown
moulding。crown moulding是现成的prime好的，baseboard是red oak，要stain加
clear finish的。是要从头做，材料也是要买。。。虽然都是从没做过，但是粗粗计划
，想着一天半就行了，所以以为两天周末基本full time做，怎么都完成了。。。。。
可事实上，两个中一个都没有完成。总是有没想到的task或意外跑出来。。。。
两天最后baseboard做了，买了材料，拆下原来的，因为高度不对，所以要补paint，
cut baseboard to size, stain baseboard, apply first coat of clear finish；
crown moulding做了，买了材料，学习了一下咋做，crown |
|
|
g****r
发帖数: 306 | 26 My interpretation:
With the earnings season coming to an end and the 3 indexes at such a high
level, the market may well deserve a significant pullback or break.
Solar and shipping stocks may still offer some speculative opportunities
before their ER announcements in the next few weeks to come.
A good article to read for generally understanding the market behavior.
-------------------------------------------------------------------
Greece Fear Factor May Have Caused Most to Miss Rally
Published:... 阅读全帖 |
|
o******r
发帖数: 259 | 27 为了考察哪个journal 更容易,特统计了graphics 领域journals的
近几年Impact Factor和rank
note:
1. IF 02-05 是平均值,排序, 根据ISI Citation Indices 02-05计算得到
2. 有几个journal已经改名,放一块了,能从相同数据看出来
2. rank 由 http://appsrv.cse.cuhk.edu.hk/~chhoi/jrank.htm获得
3. IF 2003 和 Rank 2003 : http://citeseer.ist.psu.edu/impact.html
感谢版主大人提供部分journal title
copy 如下内容,存成.csv用 exel看即可,仅供参考,希望对大家有点用
Name, IF 02-05, IF 2005, Articles 05, IF 2004, IF 2003, IF2002, Rank, IF
2003, Top 2003, Country
IEEE Transactions on Pattern Analysis and Machine Intelli |
|
b********n
发帖数: 38600 | 28 http://www.usatoday.com/story/money/business/2014/04/19/cnbc-be
10 best jobs for 2014:
1. Mathematician
Change from ranking on 2013 list: Up 17
Midlevel income: $101,360
Key factors for ranking: work environment, high income and outlook, low
stress
These are the people who figure out if a decision makes sense for a company
or organization, be it digging for oil or building a car. They work in a
variety of sectors, including energy, transportation and IT. "Mathematicians
have historically been th... 阅读全帖 |
|
f*******o
发帖数: 150 | 29 Impacting our young
Much has been written about impact factors, how they are calculated, and what they do and do not
measure. Briefly, the Institute for Scientific Information (ISI) impact factor is calculated for each
journal as the number of citations per paper published in that journal in the prior 2 years. When
the 2-year impact factor was designed, it was intended to be an aid to librarians making decisions
about which journals to purchase so that they could get a rough sense of a journal's... 阅读全帖 |
|
f**d
发帖数: 768 | 30 这是一本计算神经科学的优秀著作，全文拷贝这里（图和公式缺），有兴趣的同学可以
阅读
如需要，我可以分享PDF文件（－－仅供个人学习，无商业用途）
From Computer to Brain
William W. Lytton
From Computer to Brain
Foundations of Computational Neuroscience
Springer
William W. Lytton, M.D.
Associate Professor, State University of New York, Downstato, Brooklyn, NY
Visiting Associate Professor, University of Wisconsin, Madison
Visiting Associate Professor, Polytechnic University, Brooklyn, NY
Staff Neurologist., Kings County Hospital, Brooklyn, NY
In From Computer to Brain: ... 阅读全帖 |
|
w********g
发帖数: 1529 | 31 Definition and Computation of Target Bonus Award
3.1 “Actual EVA” means the EVA as
calculated for each Participating Group for the year in question.
3.2 “Target EVA” for the year in question
means the level of EVA that is expected in order for the Participating Group
to receive the Target Bonus Award. Target EVA for the year in question is
determined as follows:
4
--------------------------------------------------------------------... 阅读全帖 |
|
g*2
发帖数: 658 | 32 Overview of running injuries of the lower extremity
Author
Lisa R Callahan, MD Section Editor
Karl B Fields, MD Deputy Editor
Jonathan Grayzel, MD, FAAEM
All topics are updated as new evidence becomes available and our peer review
process is complete.
Literature review current through: Feb 2012. | This topic last updated: Oct
20, 2011.
INTRODUCTION — Running is one of the world’s most popular forms of
exercise, with millions of regular participants. In the United States alone,
up to 40 mil... 阅读全帖 |
|
J******s
发帖数: 7538 | 33 117
Maha-cattarisaka Sutta
The Great Forty
Translated from the Pali by
Thanissaro Bhikkhu
南传中部 第117经
大四十经
巴译英：谭尼莎若比丘
I have heard that on one occasion the Blessed One was staying at
Savatthi, in Jeta's Grove, Anathapindika's monastery. There he addressed
the monks: "Monks!"
"Yes, lord," the monks replied.
我是这样听说的:有一个时候佛陀住在舍卫国祇树给孤独园，他对比丘们说：
“比丘们！”
“世尊！”比丘们回答说。
The Blessed One said, "Monks, I will teach you noble right concentration
with its supports and requisite conditions. Listen, and pay close... 阅读全帖 |
|
w******y
发帖数: 4871 | 34 Febrile seizures
Author
Marvin A Fishman, MD
Section Editor
Douglas R Nordli, Jr, MD
Deputy Editor
Janet L Wilterdink, MD
Last literature review version 19.1: January 2011 | This topic last updated:
February 3, 2011 (More)
INTRODUCTION — Febrile seizures are a common cause of convulsions in young
children. They occur in 2 to 4 percent of children younger than five years
of age, but the incidence is as high as 15 percent in some populations. This
incidence has been attributed to closer living arr... 阅读全帖 |
|
q*d
发帖数: 22178 | 35 ☆─────────────────────────────────────☆
swjtuer (swjtuer) 于 (Tue Mar 30 23:56:30 2010, 美东) 提到:
星期一
早餐 牛奶，煮鸡蛋，玉米馒头，榨菜
早点 芦柑
午餐 中大：绿豆饭，木须肉，海米冬瓜，棒骨菠菜汤
小婴：绿豆饭，三叶瓜炒肉，海米冬瓜，棒骨菠菜汤
午点 冰糖山楂水，蔬菜饼
晚餐 棒骨冬苋菜瘦肉粥，卤肉秋叶夹馍
星期二
早餐 牛奶，蒸鸡蛋，枣泥糕
早点 香蕉
午餐 中大：胡萝卜饭，芹菜炒牛肉，珊瑚豆腐，棒骨凤尾汤
小婴：胡萝卜饭，芹菜炒肉，珊瑚豆腐，棒骨凤尾汤
午点 果汁，卤猪肝
晚餐 豌豆肉末焖饭，番茄虾皮紫菜汤
星期三
早餐 南瓜粥，卤蛋，如意肉卷
早点 脐橙
午餐 中大：金银饭，咸烧白，海米儿菜，棒骨冬苋菜汤
小婴：金银饭，樱桃肉，海米儿菜，棒骨冬苋菜汤
午点 牛奶，蛋卷
晚餐 米饭，蒜苔炒肉，芙蓉蒸蛋，棒骨海带萝卜汤
星期四
早餐 牛奶，蒸鸡蛋，奶香馒头
早点 苹果
午餐 中大：南瓜饭，什锦鱼丸，韭菜炒豆干，番茄菌类鱼汤
... 阅读全帖 |
|
b****n
发帖数: 8 | 36 Address:
Email:
Cell phone:
Work phone:
Oct 28, 2013
Department of Homeland Security
USCIS Nebraska Service Center
P.O. Box 87103
Lincoln, NE 68501-7103
I-140 Immigration Visa Petition Under First Preference EB-1
Petitioner/Beneficiary: XX Z., Ph.D.
Category of Petition: Alien of Extraordinary Ability
Classification Sought: 203(b)(1)(A)
Nature of Submission: Original Submission
Dear Immigration Officer,
This letter is respectfully submitted in s... 阅读全帖 |
|
b****n
发帖数: 8 | 37 Address:
Email:
Cell phone:
Work phone:
Oct 28, 2013
Department of Homeland Security
USCIS Nebraska Service Center
P.O. Box 87103
Lincoln, NE 68501-7103
I-140 Immigration Visa Petition Under First Preference EB-1
Petitioner/Beneficiary: XX Z., Ph.D.
Category of Petition: Alien of Extraordinary Ability
Classification Sought: 203(b)(1)(A)
Nature of Submission: Original Submission
Dear Immigration Officer,
This letter is respectfully submitted in s... 阅读全帖 |
|
l*****o
发帖数: 26631 | 38 Long-Term Health Risks and Benefits Associated with Spay / Neuter in Dogs
Laura J. Sanborn, M.S.
May 14, 2007
Precis
At some point, most of us with an interest in dogs will have to consider
whether or not to spay / neuter our pet. Tradition holds that the benefits
of doing so at an early age outweigh the risks. Often, tradition holds sway
in the decision-making process even after countervailing evidence has
accumulated.
Ms Sanborn has reviewed the veterinary medical literature in an exhaustive
a... 阅读全帖 |
|
R******o
发帖数: 1572 | 39 http://www.betanews.com.cn/iphone/2013-09-05/4971.shtml
前言
2012年，苹果将旗下的 MacBook Pro 15 系列升级到 Retina 显示屏幕。众所周知，
Retina 显示比以往的屏幕显示更清晰，锐利，但是很少有人知道这种技术背后的原理
，这里简单，抽象地解释一下。 一直以来我们都有一个认识，位图不是点对点输出的
话是会变模糊的。那么究竟是那个点对那个点呢？一般我们将第一个点叫做用户界面，
第二个点叫做输出界面。长久以来我们有一个误会，用户界面和输出界面都是用像素来
表示的。诚然，在 Retina 发布以前，这种概念错误也是无伤大雅的。但当 Retina 发
布后，这种概念需要纠正了。
点不等于像素
图像从计算机输出经过一套渲染过程，概括来说分成三步：用户界面布置，图层送入渲
染器，输出。Windows 的使用经验获知，设定桌面分辨率就是设定输出的分辨率。一般
来说，这样的概念没有错。如果将 Windows 的渲染分成三步，每次改变一个用户界面
元素都是对用户界面进行一次布置；改变后的图层送入渲染器进行渲染和合并图层；... 阅读全帖 |
|
m*f
发帖数: 8162 | 40 looks like no obvious pattern?
>>> factors(1 + 2)
[]
>>> factors(1 + 2 * 4)
[3]
>>> factors(1 + 2 * 4 * 6)
[7]
>>> factors(1 + 2 * 4 * 6 * 8)
[5, 7, 11]
>>> factors(1 + 2 * 4 * 6 * 8 * 10)
[23]
>>> factors(1 + 2 * 4 * 6 * 8 * 10 * 12)
[7, 29, 203]
>>> factors(1 + 2 * 4 * 6 * 8 * 10 * 12 * 14)
[167]
>>> factors(1 + 2 * 4 * 6 * 8 * 10 * 12 * 14 * 16)
[19]
>>> factors(1 + 2 * 4 * 6 * 8 * 10 * 12 * 14 * 16 * 18)
[29, 173, 841, 1277, 5017]
>>> factors(1 + 2 * 4 * 6 * 8 * 10 * 12 * 14 * 16 * 18 * 20)
... 阅读全帖 |
|
i*******6
发帖数: 234 | 41 fHere are some references about the relation between milk comsumption and
prostate cancer.
1. World Cancer Research Fund/American Institute for Cancer Research. Food,
Nutrition, and the Prevention of Cancer: A Global Perspective. American
Institute for Cancer Research, Washington, D.C., 1997, p. 311.
2. Chan JM, Stampfer MJ, Giovannucci EL. What causes prostate cancer? A
brief summary of the epidemiology. Sem Canc Biol. 1998a;8:263-73.
3. Howell MA. Factor analysis of international cancer mortal... 阅读全帖 |
|
s******s
发帖数: 63 | 42 根据楼上的某个版本写的 大概1秒可以run ~1，000，000 长度的输入
import sys
def prime_factors(n):
pf={}
prime = 2
while n>=prime:
if n%prime == 0:
pf[prime] = 1
n = n/prime
while n%prime==0:
n = n/prime
pf[prime] = pf[prime]+1
prime = prime + 1
return pf
def main(s):
n = len(s)
sl = set(s)
if n <= 1 or n==len(sl):
return 1
pf = prime_factors(n)
print(pf)
multiplier = 1
for factor in pf:
while pf[factor]>0:
divide = 1
for i in range(f... 阅读全帖 |
|
|
|
o******e
发帖数: 1761 | 45 感觉是没用的，劳工法规定的很明确：
This fact sheet provides general information concerning what is a "private
home" for purposes of domestic service employment under the FLSA.
Who Is a Domestic Service Worker?
Domestic service workers provide services of a household nature in or about
a private home. Persons employed in domestic service in private homes are
covered by the FLSA. Domestic service workers include companions,
babysitters, cooks, waiters, maids, housekeepers, nannies, nurses, janitors,
caretakers, ha... 阅读全帖 |
|
o******e
发帖数: 1761 | 46 感觉是没用的，劳工法规定的很明确：
This fact sheet provides general information concerning what is a "private
home" for purposes of domestic service employment under the FLSA.
Who Is a Domestic Service Worker?
Domestic service workers provide services of a household nature in or about
a private home. Persons employed in domestic service in private homes are
covered by the FLSA. Domestic service workers include companions,
babysitters, cooks, waiters, maids, housekeepers, nannies, nurses, janitors,
caretakers, ha... 阅读全帖 |
|
o******e
发帖数: 1761 | 47 感觉是没用的，劳工法规定的很明确：
This fact sheet provides general information concerning what is a "private
home" for purposes of domestic service employment under the FLSA.
Who Is a Domestic Service Worker?
Domestic service workers provide services of a household nature in or about
a private home. Persons employed in domestic service in private homes are
covered by the FLSA. Domestic service workers include companions,
babysitters, cooks, waiters, maids, housekeepers, nannies, nurses, janitors,
caretakers, ha... 阅读全帖 |
|
o******e
发帖数: 1761 | 48 感觉是没用的，劳工法规定的很明确：
This fact sheet provides general information concerning what is a "private
home" for purposes of domestic service employment under the FLSA.
Who Is a Domestic Service Worker?
Domestic service workers provide services of a household nature in or about
a private home. Persons employed in domestic service in private homes are
covered by the FLSA. Domestic service workers include companions,
babysitters, cooks, waiters, maids, housekeepers, nannies, nurses, janitors,
caretakers, ha... 阅读全帖 |
|
