w***n
发帖数: 1084 | 1 大师，我知道你爱把sample叫做individual，把a group of samples叫做sample。
你爱怎么发明创造不管，但你不能那你的用词来理解我们的用词，就说sstatistics有confused concept，也太搞笑了吧。
别人都清楚得很。要confuse也是你自己confuse。 |
|
d*********k
发帖数: 1239 | 2 对这种sample size不一样的时候怎么办啊?
比如这个题的话，是不是这样啊：
1）对A random sample （with replacement）13 个，对B random sample （with
replacement）8 个，然后做T-test一次的到一个P-value
2） 对以上的步骤 1）重复100次，得到100个P value.
3） 可以计算得到 p value的 95%的CI.
这样的步骤对么？
谢谢啦啊 |
|
d*********k
发帖数: 1239 | 3 比如这个题，A 有13个，B有8个，我sample的时候，不一定要保持A 13个，B 8个？
随便sample几个都行么？比如对他们都sample同样8个，10个， 20 个，30个的？都行
么？ |
|
w***e
发帖数: 35 | 4 不知道我的理解对不对。
过去做Bayesian Analysis的时候，可以用gibbs sampling, M/H sampling, and slice
sampling等方法针对 posterior distribution 进行采样。对于采样的结果是否符合
要求，通常会对采样的结果做一个Convergence的测试。如果证明Converge了，就认为
采样的结果可以用于进一步的分析。
的， |
|
s*********y
发帖数: 34 | 5 现在准备对一个区的客户抽样, 进行产品价格反应调查. 抽样的客户准备分三个组, 每
个组给邮寄不同giftcard 面值如果他们购买产品, 所有客户的产品价格都一样. 目的
的比较不同的giftcard对购买率的影响.
怎么计算Sample Size? SAS 里面是有Sample Size的计算,但是是基于正太分布的
numerical data.我现在的这个实验是Categorical Data Analysis.
大家能推荐本计算Sample Size的书. |
|
s*********y
发帖数: 34 | 6 怎么计算Sample Size? SAS 里面是有Sample Size的计算,但是是基于正太分布的
numerical data.我现在的这个实验是Categorical Data Analysis.
大家能推荐本计算Sample Size的书. |
|
k*****u
发帖数: 1688 | 7 naive method:
proc surveyselect to sample again and again until sample mean=20, otherwise
sample again and again~~~~~~~ |
|
D******n
发帖数: 2836 | 8 同样的要使得 good : bad = 1:1 （maybe originally 9:1)
为什么有人用under-sampling? 保留所有bad，然后取相同数目的good。
为啥不用weighting， 把good weight down (bad weight=1, good weight=1/9 ) ?
是不是因为，under-sampling 之后sample更少
或者后面进行的建模不一定可以使用weight？ |
|
a****t
发帖数: 1007 | 9 有这样一个实验，population挺大的（具体多少，我目前不知道，但我可以问），我需
要在4个时间点抽出一些样品来分析，检测某个parameter，判断是否合格，以此来推断
整个population的情况（有点像测试defect）。我知道在SQC里面可以查表格知道
sample size，但是那是在一个时间点上的测试的情况。现在在4个不同时间点上测试相
同数目的样品，那是不是把表格得到的sample size除以4，还是其它的方法？计划每个
时间点上测20个sample，不知道够不够？谢谢。 |
|
k*******a
发帖数: 772 | 10 1. 先 sample z~bernuolli(w), 然后如果 z=1 那么 sample N(0,1) 如果z=0那么
sample N(1,1)
2. 没看懂啊。。。 |
|
f**********i
发帖数: 206 | 11 用latin hypercube sampling方法产生sampling时，发现用两种不同的工具产生的结果
完全不一样。我用matlab code 做lhs时，每次产生的sampling都很随机。就是同一个
code，我每run一次给出的结果都不一样。我用另一个软件做lhs时，只要给定了最大值
，最小值和样本数，结果始终一样。用两种做法，都是假定参数是uniform
distrubution。我猜测的解释是：前者没有correlation matrix，在code中有一个矩阵
是随机产生的，所以最终结果也很随机。后者是因为加入了correlation matrix。我完
全是在黑箱操作lhs。不知道这个解释对不对？
我本人不是统计的，只是在做自己相关研究时要用到lhs。可是这个lhs是后面工作的基
调。如果lhs做错了，意味着后面的结果全错。所以lhs非常关键。想问的问题很多：
（1）假定参数是均匀分布的，lhs是不是只有一种方法？为什么我用两种不同的工具得
到的结果完全不一样？就像上面说的那样。
（2）大家如果要用到lhs，一般都是怎么做的？
（3）使用的lhs会影响到后面emul... 阅读全帖 |
|
T*******I
发帖数: 5138 | 12 The "independence" of a sample should mean that each individual (here is a
patient) in a sample is independent to all others. So, your sample can be
treated as three independent groups:
Use A only
Use B only
Use A and B
You can take the simple ANOVA with interaction A*B. I believe the model can
be
Effect = groups(include A, B and A+B) + A*B + adjusters( age, gender)
or stratified models by categorized Age groups, or Gender, etc.
At leaset, the effect models established here can help you to find
... 阅读全帖 |
|
y*****w
发帖数: 1350 | 13 By "matched sample", you are right, paired data analysis should be applied.
However, this is still not a strictly matched sample by any means. LZ would
have to prove that the samples were matched through some mechanism (age and
gender matching, as a simple example), not arbitrarily.
LZ can check out the following article by Peter Austin. It's about
propensity score matching, with some contents on survival analysis (K-M
estimates and Cox models) in the context of matched pairs. Check out Page
113... 阅读全帖 |
|
h**t
发帖数: 1678 | 14 What formula can I use to determine the right sample size for clustering
analysis with 100-300 variables?
What sampling methodology can be used for k-means or hierarchical clustering
on categorical fields so that all values of the categorical fields are
included in the sample?
Thanks a lot! |
|
a****g
发帖数: 8131 | 15 how about that
for each case, do a matched sampling of 5 controls
iterate all cases
clearly this will be an calculation expensive
alternatively, suppose you have 100 cases,
ask for a random sampling of 500 controls with equal weight on the labels
I haven't done any sampling for a lot time thus cannot write a code for you.
just some thoughts to share with you.
the |
|
c***z
发帖数: 6348 | 16 Hi all,
I was asked a question about sample size and I forgot how to answer it.
Here it is: suppose we want to predict market share of 5 products, what is
the minimal sample size we need so that the error is less than 1%?
I have never worried about sample size since we have billions of records...
But since the boss asked, I need to worry about it now...
Can anyone help me? Is this called the power analysis?
Thanks a lot! |
|
c***n
发帖数: 921 | 17 I have one idiea and not sure if it is valid or not.
I will create a new sample data, which is called S.
I can re-sample the Asia portion of the sample data, and make it 25% of the
entire users of S. The same rules for other continents.
Then performing analysis on S.
Is this method theoretically sound? Is there any theory support this?
Another other suggestions please? |
|
a****y
发帖数: 1035 | 18 电面了一下hiring manager， 结束的时候要求发一份sample program过去， 请问这种
sample一般是发
什么样的sample过去？
补充一下，电面的时候聊了做的projects， 问了用什么软件，我主要是用过R 和 SAS
， 是不是找个做过的code 文件发过去就行？需要另外黏贴到文本文件里面吗？
第一次，不太懂，谢谢指教！！ |
|
d******9
发帖数: 134 | 19 Suppose有两个studies A & B.
Study A有300 subjects，已知这300 subjects summary level的 baseline clinical
characteristics. （e.g. mean, SD for age, blood pressure, etc.)
Study B有1000 subjects, 已知每个subject的baseline clinical characteristics.
如果想从study B中sample 300个subjects, 希望这个sample的summary level的
baseline clinical characteristics和study A一样，可以用什么样的sampling方法呢?
多谢~ |
|
n**********0
发帖数: 66 | 20 不懂你的意思。如果mean差那么大，那你就不可能是random sample也不
representative了吧。如果你是有bias的选择，那怎么着都行了 |
|
g******2
发帖数: 234 | 21 I guess you are talking about truncated distribution. Find a threshold T
such that E(X|X>T)=145, and then sample 100 points from X|X>T. |
|
w*******y
发帖数: 60932 | 22 Link:
http://www.lancome-usa.com/specialoffers/
With any purchase receive free shipping and free deluxe samples of Genifique
and Genifique Eye (together a $67 value). No code needed.
Use code fs2010 for bifacils & definicils deluxe samples
+ choose extra sample for lancome.com registered members
|
|
w*******y
发帖数: 60932 | 23 Sign up at Link:
https://www.pgeverydaysolutions.com/pgeds/brandsampler.jsp?site_source=en_us
&referrer=October10Newsletter-site&utm_source=eds&utm_medium=crm&utm_
campaign=October10Newsletter
and choose your coupons/prodcucts.
Free sample of Head & Shoulders - 10 ml
Free sample of Pantene's new product
A coupon for Bounty paper towels
A coupon for $0.50 off Bounty Quilted Napkins
A coupon for $2.00 off Gillette Fusion ProGlide
A $0.75 off any ONE Zest Bar or Body Wash
A free sample of Prilosec |
|
|
w*******y
发帖数: 60932 | 25 Kiehl's is offering 10 free samples with any purchase while supplies last
with code GALORE. They also have a code for their #1 Lip product using the
code KISSES. I ordered one lip balm and got one free + 10 free samples and
my total was 12.99. You could alternativel y use code FALLAFF and get free
shipping if your order totals 25.00 or more. Please note GALORE says "not
applied" yet spoke with customer service and they are aware and note it IS
allowing the adding of ten samples. Enjoy
www. |
|
w*******y
发帖数: 60932 | 26 Free Sample: Don't wait another moment. Try OXYClinical today.
Link:
http://www.oxyskincare.com/free-sample
Available[/url] in the USA only. Limit one (1) per household while supplies
last.
Single Application Sample includes:
OXYClinical
Clearing Treatment
0.14 OZ (4 g)
OXYClinical
Hydrating Therapy
0.18 OZ (5 g)
OXYClinical
Advanced Face Wash
0.32 FL OZ (9.5 mL)
|
|
w*******y
发帖数: 60932 | 27 I got an email from 3M with this link to a free Post-It sample:
Link:
http://www3.3m.com/qfrm/ShowSurvey?surveyid=JOJOPQK0
I can't figure out WHAT the sample is going to be, BUT the form is short and
quick so I went ahead and submitted it.
Thought I would pass this "warm" deal on for anyone who wants a mysterious
free sample from Post-It. LOL
|
|
w*******y
发帖数: 60932 | 28 Walmart is offering 2 free samples of Emergen-C, one Calcium and Vitamin D/
Bone Health formula and one Immune++
Link:
http://www.startsampling.com/sm/immuneplus/captureAddress.iphtml?item=101354
I know a while back there were free samples available thru the Emergen-C
website and they only allowed one per household. That being said, this
should allow those who got those samples to do it again!
|
|
|
w*******y
发帖数: 60932 | 30 Another ULTA deal. I got in on the deal posted last week for a free robe
with $30 fragrance purchase (still available) and a bag with 9 samples with
any $25 purchase. They now have a free tote with any $16 Ulta.com bath (full
size products) purchase that can be combined with the other freebies. Many
makeup items are also currently B1G1 or B2G2.
For a total of $27.75 shipped, I got 2 eye primers (currently B1G1), 2 full
size bottles of ULTA bubble bath, L'Oreal Kids Conditioner and detangler on
c... 阅读全帖 |
|
|
w*******y
发帖数: 60932 | 32 Target is offering the Target Beauty Sample Bag for free with a brief survey
. Includes samples of Nivea, Olay, Suave, Herbal Essences, Neutrogena, and
other products.
Link:
http://samples.target.com/beauty-bag/
|
|
w*******y
发帖数: 60932 | 33 Garnier offers a free Garnier Fructis Pure Clean Shampoo and Conditioner
Sample via a short form. . Limit one sample per household. Pure Clean
shampoo is 94% biodegradable, and the conditioner is 92% biodegradable.
Allow 4 to 6 weeks for delivery.
Link:
http://www.garnierusa.com/_en/_us/pure_clean/index.aspx#/home
#/home" rel="nofollow" target="_blank" onclick="_gaq.push(['_trackEvent', '
thread', 'click', '2858551 - garnier-fructis-pure-clean-shampoo-conditioner-
sample-for-free']);">http://www... 阅读全帖 |
|
w*******y
发帖数: 60932 | 34 Lancome Free 10-piece Samples + free shipping with any $35 purchase today
only.
Free 10-piece Samples + free shipping with any $35 purchase. Use codes
FALLEYES and FALLGLAM at check out. Valid 9/18 only or while supplies last.
Total you can get 12 free samples+FS
Just received confirmation email.
|
|
w*******y
发帖数: 60932 | 35 I played Sephora's "Beauty Roulette" promo linked from their email: Link:
http://www.sephoralove.com/beautyroulette/
The codes you can "win" are not one-time use, so here they are...
Free Shipping over $25 (usually this is $50): F2Y11S9
Deluxe Sample of Buxom Lash Mascara (0.2 oz, $9 value): B2Y11S9
Deluxe Sample of Urban Decay Lip Junkie Gloss (0.12 oz, $7 value): U2Y11S9
Deluxe Sample of Murad Essential C-Day Moisture SPF 30 (0.33 oz, $12 value):
M2Y11S9
Codes expire 10/31/11
HTH!
|
|
w*******y
发帖数: 60932 | 36 Free sample of Barista Prima Coffeehouse K-Cup by mail. From Target.com
Hurry. Target samples go fast.
Link:
http://samples.target.com/
|
|
w*******y
发帖数: 60932 | 37 5 FREE Holiday Greeting Card Samples From Tiny Prints
To get 5 FREE Holiday Greeting Card Samples From Tiny Prints find the
holiday card(s) that you would like and then select the "Order Sample" link
next to the personalize button. Enter promo code: 5HOLIDAY at checkout to
get as many as 5 for FREE plus FREE shipping!!!
Link:
http://www.tinyprints.com/shop/holiday-cards.htm?
|
|
w*******y
发帖数: 60932 | 38 Clinique is running a promotion at Nordstrom right now in stores and online.
You get a 8-piece Tracy Reese for Clinique gift set with $25 purchase.
Link:
http://shop.nordstrom.com/c/clinique-gift-with-purchase-details
I think its a pretty good deal.
Also, when I checked out, Nordstrom also gave me a set of perfume samples
for free!
Free shipping if purchasing online.
Get our exclusive Tracy Reese for Clinique gift with your $25 Clinique
purchase--a $75 value. Online and in store.
Gift includes:
... 阅读全帖 |
|
G*******s
发帖数: 10605 | 39 【 以下文字转载自 SmartShopper 俱乐部 】
发信人: GoRockets (火箭加油), 信区: SmartShopper
标 题: Free sample of Nature's Path Granola Bars Shop
发信站: BBS 未名空间站 (Mon Nov 7 22:11:56 2011, 美东)
The Ellen DeGeneres Show offers a sample of Nature's Path Granola Bars for
free when you fill out this short form. That's the best deal we've ever seen
for these bars. You must choose a sample of Chococonut, Pumpkin-N-Spice,
Lotta' Apricotta, or Berry Strawbery flavors.
http://userquote.com/forum/index.php?topic=870.msg1118#msg111... 阅读全帖 |
|
|
|
w*******y
发帖数: 60932 | 42 Click on "Get a Sample" (use the arrows if you don't see it) and fill out
the form to receive a free sample of Huggies Diapers Snug and Dry sample.
Choose from Size 3 (16 - 28 lbs), Size 4 (22 - 37 lbs) or Size 5 (over 27
lbs).
Note: Sam's Club # is NOT required.
Link:
http://www5.samsclub.com/showcase/KC-Baby-Showcase.aspx
|
|
w*******y
发帖数: 60932 | 43 FREE BOSS Bottled and BOSS Bottled Night Fragrances Sample @ Boss.
Link:
http://www.boss-fragrances.com/sample/sample.aspx?&lc=us
Note - Sometimes URL doesn't work in Chrome and you can't see "Submit"
button. Try with other browsers.
I had issues with Chrome and it went through in Firefox.
|
|
w*******y
发帖数: 60932 | 44 Free Sample (11oz.) reGen Muscle Recovery Beverage at select GNC stores.
Linky: http://www.active.com/images/newsletters/Hershey-reGen/01192012-Male/index-2.html [Free Sample reGen Muscle Recovery Beverage]
How will reGenimprove your workouts? It is proven to speed recovery and
increase endurance when consumed within 60 minutes of exercise.*
The reGendifference:
o 12g natural cocoa
o 3:1 carb:protein ratio
o Rich, chocolate taste
reGenbeverage is a food product, NOT a supplement and is specially... 阅读全帖 |
|
w*******y
发帖数: 60932 | 45 I don't usually post in deals so go easy on me I am both a makeup and a
deal lover, and I thought this was pretty good, It would make for a cute
VDay gift as well!
Add this mini black and pink satin makeup bag:
https://www.toofaced.com/p-1038-mini-black-pink-satin-bag.aspx
to your cart.
free beauty balm sample will automatically be added and you will be given a
choice of one of the following deluxe samples:
Deluxe Glamour Gloss in Barely Legal
Deluxe Glamour Gloss in Pillow Talk
Deluxe Lash I... 阅读全帖 |
|
|
w*******y
发帖数: 60932 | 47 Origins:
http://iway.org/9620191
3-4 Week Supply Beauty Samples:
http://iway.org/9620201
Free w/ any purchase
Starting Over Eye Creamoffer code EYE
Checks & Balances Face Washoffer code CLEANSE
A Perfect World Moisturizeroffer code MOISTURE
Plantscription Anti-Aging Serumoffer code ANTIAGING
Some inexpensive items to buy to qualify for one the free sample kits listed
above:
Checks & Balances Face Wash:
http://iway.org/9620211
(1.7-oz) $10
Peace Of Mind:
http://iway.org/9620221
$11
Quick Hi... 阅读全帖 |
|
w*********s
发帖数: 2136 | 48 http://pics.livejournal.com/a_kolesnichenko/pic/00021ace/s640x480
Medvedev Shows Off Sample Coin of New ‘World Currency’ at G-8
By Lyubov Pronina
www.bloomberg.com
July 10 (Bloomberg) -- Russian President Dmitry Medvedev illustrated his
call for a supranational currency to replace the dollar by pulling from his
pocket a sample coin of a “united future world currency.”
“Here it is,” Medvedev told reporters today in L’Aquila, Italy, after a
summit of the Group of Eight nations. “You can see it and |
|
j****e
发帖数: 264 | 49 The dealer offers this price for me. The car is a brand new 2010 Nissan
Altima 2.5 SL displayed in the hall of the dealer store. I am not sure if
this price is proper for a sample car. The bad thing is that I can not
choose the color of the car... ...
Another question is that what should I watch out to buy a brand new sample
car? Thanks! |
|
M****o
发帖数: 13571 | 50 不建议交易打印胖子；胖子是免费的，收费的是服务:
Not 胖子
出售/交换物品的名称:
Similac Isomil Sample formula, 3x cans
物品类别（coupon：mfc等；血糖仪等）:
Similac Isomil Sample formula, 3x cans
including:
2x Isomil Advance
1x Sensitive Isomil
物品来源（报纸夹页，厂家邮寄等）:
厂家邮寄
可接受的价格（必须明码标价，必填）:
$6 包邮费
邮寄损失方式哪方承担（若需邮寄，必填）:
before me, after you
付款方式说明:
Non-cc PayPal
本贴有效期（必填）:
till gone
联系方式（例： 站内）:
mitbbs mail only |
|
