c**i
发帖数: 6973 | 1 (1) Robots | Zoobotics; A new generation of animal-like robots is about
to emerge from the laboratory. Economist, July 7, 2011
http://www.economist.com/node/18925855
Note:
(a) phylum (n; New Latin, from Greek phylon tribe, race; First Known Use:
1876):
" a group that constitutes or has the unity of a phylum; specifically : a
primary category in biological taxonomy especially of animals that ranks
above the class and below the kingdom"
www.m-w.com
(b) R2-D2
http://en.wikipedia.org/wiki/R2-D2
(... 阅读全帖 |
|
c****e
发帖数: 1453 | 2 发信人: ayanami (螃蟹@FROSTSHOCK PWNS YOU!!11!), 信区: Linux
标 题: Re: [原创] emacs和vim的区别。
发信站: BBS 未名空间站 (Mon Mar 16 14:18:17 2009)
How do you do "%" ?
(global-set-key "%" 'match-paren)
(defun match-paren (arg)
"Go to the matching paren if on a paren; otherwise insert %."
(interactive "p")
(cond ((looking-at "\\s\(") (forward-list 1) (backward-char 1))
((looking-at "\\s\)") (forward-char 1) (backward-list 1))
(t (self-insert-command (or arg 1))))) |
|
z*****k
发帖数: 600 | 3 There is no good backward player. To play a video backward, special care has
to be taken on encoding, or do a transcoding.
VLC or Mplayer/gmplayer is as good as you can get.
Or if you know enough about video, ffmpeg. It has transcoding tools as well. |
|
w***g
发帖数: 5958 | 4 JVM本来是被设计成跑在微波炉上的。等generic需求出现的时候发现如果要做reified
generics的话就得改bytecode specification，老的JVM就没法跑新的bytecode。这个
是所谓的backward compatiblity的问题。Java是1994年发明的。2004年引入generics
。现在是2014年。Scala是JVM上的语言，也无法实现reified generics。当年支持
backward compatibility的决定是对是错应该没有一个公认的看法吧。不然OpenJDK也
不会搞出一个改进JVM的project来了。不过现在再改我倒觉得真的是晚了。 |
|
b***e
发帖数: 17 | 5 JVM was designed a long time ago and some of the design choices were made in
restricted ways such that some certain modern features are difficult to
extend. It's a dilemma given that Java needs to maintain its backward
compatibility. To this point, Java's doing much better than Ruby or Python,
which are not always backward compatible. |
|
d****i
发帖数: 4809 | 6 Python3没有做到backward compatibility是失败的主要原因。任何语言如果没有向后
兼容都会失败，这点其他主流语言做的很好，C, C++, Java都始终一直保持backward
compatibility。你在Unix下cc一个1969年Ritche和Thompson写的C code，还能编译运
行，这就是魅力。 |
|
d******e
发帖数: 2265 | 7 转帖：
克里斯可以说是天才少年和好学生的代名词，他在2000年本科毕业之后，继续攻读计算
机硕士和博士。但克里斯并不是宅男，学习之余他手捧「龙书」游历世界，成为德智体
美劳全面发展的好学生。之后就是一篇又一篇的发表论文，硕士毕业论文即提出了一套
完整的运行时编译思想，奠定了 LLVM 的发展基础，读博期间 LLVM 编译框架在他的领
导下得到了长足的发展，已经可以基于 GCC 前端编译器的语义分析结果进行编译优化
和代码生成，所以克里斯在2005年毕业的时候已经是业界知名的编译器专家了。
注：很多计算机专业的大学生经常问我在大学里学点什么好，看看克里斯就行了。以目
前的科技信息开放程度，如果你在自己感兴趣的领域里用心耕耘，再加上那么一点点天
分，毕业时成为某一个专有领域的专家应该不是问题。那时就不是你满世界去找工作了
，而是工作满世界来找你！
克里斯毕业的时候正是苹果为了编译器焦头烂额的时候，因为苹果之前的软件产品都依
赖于整条 GCC 编译链，而开源界的这帮大爷并不买苹果的帐，他们不愿意专门为了苹
果公司的要求优化和改进 GCC 代码，所以苹果一怒之下将编译器后端直接替换为 LLVM... 阅读全帖 |
|
m******r
发帖数: 1033 | 8 是这篇文章吗 ？ http://www.utstat.toronto.edu/~brunner/oldclass/appliedf11/handouts/2101f11StepwiseLogisticR.pdf
它的输出是如下：
> # Here was the chosen model from earlier
> redmod1 = glm(low ~ lwt+racefac+smoke+ptl+ht,family=binomial)
>
> backwards = step(fullmod) # Backwards selection is the default
Start: AIC= 221.28
low ~ age + lwt + racefac + smoke + ptl + ht + ui + ftv
Df Deviance AIC
- ftv 1 201.43 219.43
- age 1 201.93 219.93
201.28 221.28
- ptl 1 203.83 221.83
- ui 1 204.03 222.03
- racefac 2 ... 阅读全帖 |
|
发帖数: 1 | 9 Why did IBM's OS/2 project lose to Microsoft, given that IBM had much more
resources than Microsoft at that time?
Great question. I'm the founder of Team OS/2 and IBM's first OS/2 Evangelist
, so I lived through the answer to your question for a decade. There's just
no easy answer - it's like asking what makes any given startup a success or
failure - but I'm happy to share the way I see it.
First a few facts - from memory - you might find relevant that support your
question.
IBM spent more than ... 阅读全帖 |
|
p****s
发帖数: 3184 | 10
(defun match-paren (arg)
"Go to the matching parenthesis if on parenthesis otherwise insert %."
(interactive "p")
(cond ((looking-at "\\s\(") (forward-list 1) (backward-char 1))
((looking-at "\\s\)") (forward-char 1) (backward-list 1))
(t (self-insert-command (or arg 1)))))
(global-set-key "%" 'match-paren)
; however, now you have to press C-q % if you want to insert a %
; when the cursor is at a parenthesis |
|
p*******r
发帖数: 4048 | 11 Because that field is so backward.
Just my style of doing science. I like to pick backward fields and try to
make them hot. :)
Most
thus |
|
p*******r
发帖数: 4048 | 12 Because that field is so backward.
Just my style of doing science. I like to pick backward fields and try to
make them hot. :)
This is like investing. I like to pick fields which are undervalued. :)
Most
thus |
|
z***n
发帖数: 30 | 13 我不太知道什么是bayesian stackelberg game.但我猜测应该是有incomplete
information的extensive form game，而且solution concept is associated with a belief system.我们一般说的stackelberg game是没有
incomplete information的，直接使用backward induction。但如果是incomplete information,那么backward induction会导致一些不合理的NE，a belief system may help.
如果以上是对的，那么它就是signaling game，至于是spence model还是sobel-
crawford model，要看设定。 |
|
l*****e
发帖数: 594 | 14 这个power contribute to pressure increment of the air 是叶片重力作功的平均功
率吗？一圈不是0吗？见笑，以前学的物理都忘了。谢谢！
direction), make velocity triangle, from absolute velocity's portion in
tangential direction, then calculate how much power contribute to pressure
increasement of the air
or airfoiled blade, normally forward+curved efficiency is smaller than
backward, let's say forward is about 50%, backward could be 60% or 70%,
calcualte total power consumes by the fan |
|
A*G
发帖数: 256 | 15 Child Development Milestone Chart
Age Physical Development Social and Emotional Development Intellectual
Development Language Development
At Birth Lies in fetal position with knees tucked up. Unable to raise head.
Head falls backwards if pulled to sit. Reacts to sudden sound. Closes eye
to bright light. Opens eye when held in an upright position. Bonds with
mother. Smiles at mother. Beginning to develop concepts e.g. becomes aware
of physical sensations such as hunger. Explores using his... 阅读全帖 |
|
c*******e
发帖数: 150 | 16 yep, agree. for options traders, implied vol sometimes is said to be "
forward-looking", whereas historical vol, no matter how fancy your
econometric method is, is always "backward-looking".
For an easy example, suppose there is this low-beta company whose realized
volatility has been hovering in the low 20s for about 2 months. but its
annual earnings announcement is in 2 days. the implied vol (especially for
super-short tenors) will and should take such scheduled events into account.
on the ot... 阅读全帖 |
|
u**x
发帖数: 45 | 17 这种题机械的用状态转移图就完了。
Below, immediate backward transitions are neglected. State chain
terminates when it arrive visited states.
以下用河此岸状况和船的位置标记每个state. 划一次船为一个transition. 每个
legal transition, 应满足仅ABCa, 能划船的条件，和下一state legal 的条件。
state0. ABCabc+boat
step1. 三种可能。
s1.1 ABab S1.2BCbc S1.3 ABCc
step2.
s2.1 ABabC+boat S2.2 ABCbc+boat S2.3 ABCac+boat (same as S2.1 Terminate.)
Step3.
s3.1 ABC S3.2 No legal transition except immediate backwards. Terminate.
S4. ABCa+boat
S5. Aa
S6 AaBb+boat
S7.1 ab S7.2 Bb
S |
|
|
D******n
发帖数: 2836 | 19 ya, if there is some prior knowledge ,just choose the ones u think are
important. Maybe 20-30 of them, then you can use forward/backward selection
methods, LARS, LASSO.
Or you can use PCA to reduce the dimension of the data.
Maybe directly using LASSO or Forward/Backward selection methods can work
too, but not sure. |
|
r*****y
发帖数: 199 | 20 If you are doing a model selection, I think you can try both stepwise or
backward. I personally prefer backward. |
|
s*******o
发帖数: 392 | 21
hi，man, thanks lot for your reply first.
you are right, subset is a nice way. Correct me if I am wrong:
Subset: if you have 160 variables, the sas would go to see what is best for
modeling with 1 variable, what is best with 2 vars, what is best.....what is
best for 159 vars. And overall, it compare to see which is best out of best
of 160 way with 1, 2, 3, 4....160 variables to predict or modeling. I would
try.
But here I did not use stepwise, I use backward which method I read
somewhere telling... 阅读全帖 |
|
r********n
发帖数: 6979 | 22 这不就是做feature selection么
你可以google一下
方法多了去了
forward， backward， AIC， BIC。。。
你说的这个例子其实就是做一个F-test(anova)
如果用更少predictor的那个model能够得到和更多predictor的model相似的fitness
那就应该选那个predictor比较少的
一般来说这样产生的model更robust
如果你只是先快速检验一下那个model可能会更好一点
可以用这个方法
不过我个人不是太喜欢这么做
因为做出来的model在新的数据里面“不一定”更好
如果愿意多花些时间的话
我一般会先做cross validatiaon或者bootstrapping
重复N次
然后比较两个model在test set里面的fitness
然后选择那个fitness error更低的那个
优点是这样做出来的model一般来说更robust
缺点是花的时间可能是几十倍甚至几百倍
如果你的feature比较多的时候
可以先用uni-variate model， forward, backward等方法找到有限的一些... 阅读全帖 |
|
w**p
发帖数: 4080 | 23 查了下楼主大概用的是SPSS。
Enter法结果最可信。其次backward，再次forward。
Enter和backward貌似结果比较一致？ |
|
m*n
发帖数: 695 | 24 谢谢您的指导！
是的， 我用的是spss.似结果比较一致, 不同的是ESX MP 在 backward 中有了意义。
Enter and backward |
|
o*s
发帖数: 623 | 25 如果你用SAS
看看这个 PROC GLMSELECT
SAS 9.4还是蛮全的
较早的版本9.2或者9.3没那么全
Forward Selection (FORWARD)
Backward Elimination (BACKWARD)
Stepwise Selection(STEPWISE)
Least Angle Regression (LAR)
Lasso Selection (LASSO)
Adaptive LASSO Selection
Elastic Net Selection (ELASTICNET)
当然R也应该都有的
相关文章：
Efron, B., Hastie, T., Johnstone, I., & Tibshirani, R. (2004). Least angle
regression. The Annals of statistics, 32(2), 407-499.
Tibshirani, R. (1996). Regression shrinkage and selection via the lasso.
Journal of the Royal ... 阅读全帖 |
|
i*********5
发帖数: 19210 | 26 Bigfuzzydoug’s Ten Points to Swimming:
http://www.beginnertriathlete.com/discussion/forums/thread-view
The key to swimming is reducing drag, not endurance or powering through the
water. This is not just my opinion; it is the law of physics. I’ll
explain it in a simple way: When you bike, you have to push air in front of
you out of the way. The bigger the frontal section of your body and bike,
the more air you have to move. What’s worse is that it’s not a one to one
relationship. An increas... 阅读全帖 |
|
o**********e
发帖数: 18403 | 27 【 以下文字转载自 SanFrancisco 讨论区 】
发信人: czjd (辽宁面团 - 第四十八浪人), 信区: SanFrancisco
标 题: 南加的资深智囊对于SCA5的评论
发信站: BBS 未名空间站 (Tue Feb 25 23:04:44 2014, 美东)
Viewpoints: A step backward on higher education enrollment
By David A. Lehrer, Richard J. Riordan and Joe R. Hicks
Special to The Bee
Published: Saturday, Feb. 8, 2014 - 12:00 am
Last week, a proposed constitutional amendment, SCA 5, passed the state
Senate with a two-thirds vote. If the Assembly takes similar action, the
people of California will soon be ... 阅读全帖 |
|
z****8
发帖数: 13 | 28 特征工程简介
原文链接：
http://mp.weixin.qq.com/s?__biz=MzIzODExMDE5MA==&mid=403826129&
（I）特征工程可以解决什么样的问题？
特征工程是一个非常重要的课题，是机器学习中不可缺少的一部分，但是它几乎很少出
现于机器学习书本里面的某一章。在机器学习方面的成功很大程度上在于如果使用特征
工程。在机器学习中，经常是用一个预测模型（线性回归，逻辑回归，SVD等）和一堆
原始数据来得到一些预测的结果，人们需要做的是从这堆原始数据中去提炼较优的结果
，然后做到最优的预测。这个就包括两个方面，第一就是如何选择和使用各种模型，第
二就是怎么样去使用这些原始的数据才能达到最优的效果。那么怎么样才能够获得最优
的结果呢？贴上一句经典的话就是：
Actually the sucess of all Machine Learning algorithms depends on how you
present the data.
—— Mohammad Pezeshki
直接翻译过来便是：事实上所有机器学习算法上面的成功都在于你怎么样去展示这些数
... 阅读全帖 |
|
z*******n
发帖数: 1034 | 29 by Jeff Martin on Jun 26, 2014 | Discuss
Details continue to emerge from Microsoft as to how the support for standard
C will be improved in Visual Studio “14”. Improving C99 compliance is a
top priority, but complementing that effort is a redesign of the familiar
mscorlib DLL. Microsoft’s James McNellis announced that the company is
splitting up Windows’ C runtime (CRT) into three distinct runtimes to
better support the needs of the various platforms that applications are
targeting.
The refact... 阅读全帖 |
|
i*********5
发帖数: 19210 | 30 Bigfuzzydoug’s Ten Points to Swimming:
http://www.beginnertriathlete.com/discussion/forums/thread-view
The key to swimming is reducing drag, not endurance or powering through the
water. This is not just my opinion; it is the law of physics. I’ll
explain it in a simple way: When you bike, you have to push air in front of
you out of the way. The bigger the frontal section of your body and bike,
the more air you have to move. What’s worse is that it’s not a one to one
relationship. An increas... 阅读全帖 |
|
i*********5
发帖数: 19210 | 31 Bigfuzzydoug’s Ten Points to Swimming:
http://www.beginnertriathlete.com/discussion/forums/thread-view
The key to swimming is reducing drag, not endurance or powering through the
water. This is not just my opinion; it is the law of physics. I’ll
explain it in a simple way: When you bike, you have to push air in front of
you out of the way. The bigger the frontal section of your body and bike,
the more air you have to move. What’s worse is that it’s not a one to one
relationship. An increas... 阅读全帖 |
|
p*********e
发帖数: 32207 | 32 ☆─────────────────────────────────────☆
yeemartin (猪头) 于 (Mon Aug 17 05:10:38 2009, 美东) 提到:
看了一篇的文章
有解释为啥Shell Rotella T、Mobil Delvac这些heavy duty diesel oil的Used oil
analysis结果都很突出的原因，普通engine oil是S certification，例如SJ、SM。商
用truck engine oil是C certification， 目前是CI、CJ。C的additive package比S的
牛x很多，但有可能会不兼容乘用车上的catalytic converter。
我的G35目前就在用Shell Rotella T，摩托车下次换油也准备用这个。mobil的
synthetic motorcycle oil 1 quart 12刀，受不了。
Commercial (Diesel) Oil
The additive packages for C (commercial) certification... 阅读全帖 |
|
w*******y
发帖数: 60932 | 33 Link:
http://www.sears.com/shc/s/p_10153_12605_05757965000P
Product Description
Sharp AQUOS BD-HP24U - Blu-ray disc player - upscaling - Netflix
Now you can enjoy the best of 1080p video on your AQUOS LCD TV. Especially
designed to work with AQUOS LCD TVs, the BD-HP24U AQUOS Blu-ray Disc player
provides seamless operability via the AQUOS LINK function through the HDMI
connection. Performing as if it were all one system, the BD-HP24U's Quick
Start feature lets you enjoy gorgeous Blu-ray Disc vide... 阅读全帖 |
|
w*******y
发帖数: 60932 | 34 Link:
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=6509554&CatId=511
EVGA 100-U3-EU30-TR SuperSpeed USB 3.0 PCI-Express Card - PCI Express X1, 2
USB 3.0 Ports
$19.99 - $10 MIR = $9.99 (less whatever cashback program you favor) + $1.99
econoshipping
The $10 EVGA rebate is valid 11/30/2010 to 12/31/2010, must be postmarked
within 30 days of purchase
ITEM DESCRIPTION:
EVGA 100-U3-EU30-TR SuperSpeed USB 3.0 PCI-Express Card
EVGA now makes it easy to upgrade to the next ... 阅读全帖 |
|
w*******y
发帖数: 60932 | 35 Radio Shack has the Air Hogs Helix 360 heli on sale for $39.99. This is a 4
channel helicopter which means you can control up/down, forward/backward,
turn right/left, and "strafe" right/left. This helicopter retails for $79.
99 at Target and was on sale for $59.99 before Christmas at Radio Shack.
Currently it appears to be out of stock online but use the tool to find
availability at B&M and price match.
Air Hogs Helix 360:
http://www.radioshack.com/product/index.jsp?productId=10940308
Ready f... 阅读全帖 |
|
w*******y
发帖数: 60932 | 36 TRENDnet TU3-S25 Removable Storage Device 2.5" USB 3.0 External Enclosure -
$14.99 + F/S
Link:
http://www.mwave.com/mwave/SKUSearch.asp?px=DS&scriteria=BA7533 TU3-S25 Removable Storage Device 2.5 USB 3.0 External Enclosure
The 2.5" USB 3.0 External Enclosure, model TU3-S25, supports one 2.5" SATA I
or II hard disk drive with storage capacities in excess of 1 Terabyte (hard
drive sold separately). Store and transfer content at blazing fast 5Gbps
USB 3.0 speeds--10 times faster than USB 2.0.
Insta... 阅读全帖 |
|
w*******y
发帖数: 60932 | 37 Link:
http://www.mwave.com/mwave/SKUSearch.asp?px=DS&scriteria=AA7934
SAVIO ST-ER20U3-BK Black SuperSpeed USB 3.0 All-In-One Universal Multi
Memory Card Reader Compatible with SDHC/SDXC UHS-1 & MSXC(Up to 2TB) $16.99
shipped
Description:
Features:
Innovative, Stylish & Compact Desgin
Data transfer rate up to 5Gbps via USB 3.0 solution
Backwards-Compatible with USB 2.0 or 1.1
5 Slots (CF, SD, MS, MicroSD & xD) for all major memory card support
Supports card-to-card file transfer between cards in ... 阅读全帖 |
|
w*******y
发帖数: 60932 | 38 TRENDnet TU3-S25 Removable Storage Device 2.5" USB 3.0 External Enclosure $9
.99 shipped
Link:
http://www.mwave.com/mwave/SKUSearch.asp?px=DS&scriteria=BA7533
Description:
The 2.5" USB 3.0 External Enclosure, model TU3-S25, supports one 2.5" SATA I
or II hard disk drive with storage capacities in excess of 1 Terabyte (hard
drive sold separately). Store and transfer content at blazing fast 5Gbps
USB 3.0 speeds--10 times faster than USB 2.0.
Install a SATA I or II hard drive and connect the enclos... 阅读全帖 |
|
y*****l
发帖数: 5997 | 39 发信人: zijing (紫晶), 信区: Stock
标 题: Re: 看到这个噩耗，教授再也淡定不住了。
发信站: BBS 未名空间站 (Wed Oct 5 20:18:05 2011, 美东)
Stanford Report, June 14, 2005
'You've got to find what you love,' Jobs says
This is a prepared text of the Commencement address delivered by Steve Jobs,
CEO of Apple Computer and of Pixar Animation Studios, on June 12, 2005.
I am honored to be with you today at your commencement from one of the
finest universities in the world. I never graduated from college. Truth be
told, this is th... 阅读全帖 |
|
i*****f
发帖数: 578 | 40 Some python packages/modules still don't support 3.x. So if you want
backward compatibility, then 2.x is the way to go. Specifically 2.7 has many
3.x features but is backward compatible.
3.x provides better syntax, better library organization, etc. So it's the
trend in the long run. |
|
d****y
发帖数: 535 | 41 儿子们上的空手道课专门讲了这个，以下是发给家长的邮件内容，当然我家俩小子还没
碰到过这种情况，但是我觉得应该很有用。
Bully Information
Parents; we hope the following information is helpful. Here are a few tools
you can use at home with your child. If you have any questions please feel
free to talk with an Instructor.
All the motivation that a child has to succeed in school, sports, and any
endeavor in life, comes from a child's confidence and self-esteem. A bully
robs a child of those very important traits that can have a negative impact
on the re... 阅读全帖 |
|
e*********w
发帖数: 367 | 42 startup是针对backward crossover说的。backward crossover看起来很唬人而且是跳
或转的起步，但学8字倒滑更容易。不过你的态度更正确，能把正滑滑顺溜了就可以了。 |
|
c**i
发帖数: 6973 | 43 (1) I am always interested in that war. (That war per se has nothing to do
with the issue at hand. If I were Pres. Hu Jintao, I would bend over
backward to seduce Japan.)
(2) I heard that shortly before that war, Qing's navy was ranked very top in
the world.
First Sino-Japanese War
http://en.wikipedia.org/wiki/First_Sino-Japanese_War
Section 2.2.2 titled "Beiyang Fleet" states, "The Beiyang Fleet was one of
the four modernised Chinese navies in the late Qing Dynasty. The navies were
heavily spon |
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l********t
发帖数: 878 | 44 【 以下文字转载自 Joke 讨论区 】
发信人: lightnight (来哥), 信区: Joke
标 题: Re: 当你被劫持并被要求用ATM卡取现金时 (转载)
发信站: BBS 未名空间站 (Wed May 5 02:49:09 2010, 美东)
Summary of the eRumor:
An alert that if you ever find yourself in a scary situation at a banking AT
M machine, such as a thief forcing you to withdraw cash, just enter your per
sonal identification number (PIN) backwards. That will automatically send a
message to the police that you are in trouble and they will respond to the m
achine. The eRumor says that most pe |
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