# topics

 1 2 3 4 5 6 7 8 9 10 下页 末页 (共10页)
 g****g发帖数: 1828 1来自主题: WaterWorld版 - Normal distributionIn probability theory, the normal (or Gaussian) distribution, is a continuous probability distribution that is often used as a first approximation to describe real-valued random variables that tend to cluster around a single mean value. The graph of the associated probability density function is “bell”-shaped, and is known as the Gaussian function or bell curve:[nb 1] f(x) = \tfrac{1}{\sqrt{2\pi\sigma^2}}\; e^{ -\frac{(x-\mu)^2}{2\sigma^2} }, where parameter μ is the mean (location of the pe... 阅读全帖
 h***e发帖数: 7320 2来自主题: _pennystock版 - [合集] Distribution Days Explained 炒股知识☆─────────────────────────────────────☆ Luckydevil (BE COOL) 于 (Thu May 20 19:36:45 2010, 美东) 提到: Will we see a rebound tomorrow? Statistically, yes, because 28 out of 41 times, the day after a Major Distribution Day (NYSE Down Volume to NYSE Up Volume Ratio > 9), such as today, was a green day. http://cobrasmarketview.blogspot.com/2010/05/05202010-after-bell-quick-summary.html ☆─────────────────────────────────────☆ dzry67 (碧水) 于 (Thu May 20 19:39:39 2010, 美东) 提到: 28/41 = 0.682 Luck... 阅读全帖
 y*****w发帖数: 1350 3来自主题: Statistics版 - Gamma distribution for power analysis,请大拿指点各位distribution大拿好，我最近有个sample size calculation project。是count data，具体说是number of patient visits, with number of episodes for each number of visit。请各位帮着参谋看一下我做的是否合适，给些意见。 Sample data如下： # patient visit episode --------------------------------- 1 156 2 287 3 589 4 899 5 1535 6 1408 7 1017 8 ... 阅读全帖
 N******n发帖数: 3003 4比如做linear regression, the coefficient beta is non negative: The prior distribution about beta has two choices: 1. 假设beta为gamma distribution, 这样可以满足non-negative的假设。 同时data 做成normal distribution, the posterior distribution 就可以做成上面两个的相乘 ，但是要想知道beta到底是什么distribution，很难因为他们两个distribution的相乘 很难转变成现有已知的distribution的样子，而且还要加上beta>0的假设。 2. 假设beta为normal distribution,并且加条件beta>0. 同时data 做成normal distribution, the posterior distribution 就可以做成上面两个的相乘，这个时候 就根据exponential family, 很容易表达成normal distribution, 还... 阅读全帖
 j**w发帖数: 382 5来自主题: JobMarket版 - Job opportunity: Distributed Computing Software EngineerPlease email resume to a********[email protected] by 9/30/2011. Opportunity Description AOL R&D in Palo Alto, CA is looking for a talented Distributed Computing Software engineer to join our Large Scale Analytics (LSA) team. In this role, you are instrumental in transforming research concepts into prototypes and software products. We value attitude, aptitude, communication skills, and coding skills over experience with specific languages and environments. Large Scale Analytics (LSA) is primarily a res... 阅读全帖
 j**w发帖数: 382 6来自主题: JobMarket版 - Job opportunity: Distributed Computing Software EngineerPlease email resume to a********[email protected] by 11/30/2011. Opportunity Description AOL R&D in Palo Alto, CA is looking for a talented Distributed Computing Software engineer to join our Large Scale Analytics (LSA) team. In this role, you are instrumental in transforming research concepts into prototypes and software products. We value attitude, aptitude, communication skills, and coding skills over experience with specific languages and environments. Large Scale Analytics (LSA) is primarily a re... 阅读全帖
 t****g发帖数: 715 7来自主题: Statistics版 - how to estimate distance between two distributions? ThanksThere are two probability distributions with known distribution functions. In addition, samples of the two distributions can be easily drawn. I need a measure to quantify the "distance" between these two distributions. And if possible, the estimator of the distance is normally distributed, or have a known distribution. For example, I can use the Kolmogorov-Smirnov distance as the measure. However, the distribution of the estimator is only known under the null that the two distributions are ide
 j********3发帖数: 27 8来自主题: JobHunting版 - SDE Opening-- Distributed (Startup in MTV)Hey guys, My company is looking for C/C++ developers. It's a big data start up and the company is located in MTV. Company sponsors H1B/Green card. Here's the job description: As a Member of Technical Staff, Core Distributed Systems, you will design and implement cutting-edge distributed, scale-out data infrastructure software systems, which is a pillar for the growing cloud infrastructure. Especially, you will bring Unix systems and server tech kung-fu to the team. You will be part of a developm... 阅读全帖
 j********9发帖数: 162 9来自主题: Mathematics版 - Copula of LogNormal Distribution?I have some questions here: Does the copula of M.R.V. LogNormal Distribution follow M.R.V. Normal Distribution? If yes, what is the covariance matrix of the copula distribution, is that the normalized characteristic matrix of LogNormal Distribution? What happen to the copula for T distribution (except Cauchy distribution) or any elliptical distribution? Can anyone recommend me some reference, online or book. I really want to make it clear. Thank you so much.
 c****g发帖数: 268 10来自主题: Statistics版 - sampling distribution 问题我在看本科的统计学课本， 里面把chi square distribution, t distribution, F distribution 都归结到sampling distribution 里面，我看不出来chi square distribution 怎么就属于sampling distribution了。 除了上述的几种分布外，还有那些分布属于sampling distribution？ 多谢
 f********x发帖数: 99 11来自主题: Programming版 - Flink Sparks Next Wave of Distributed Data ProcessingThe world beyond batch: Streaming 101: A high-level tour of modern data- processing concept http://radar.oreilly.com/2015/08/the-world-beyond-batch-streami by Tyler Akidau August 5, 2015 Editor’s note: This is the first post in a two-part series about the evolution of data processing, with a focus on streaming systems, unbounded data sets, and the future of big data. Streaming data processing is a big deal in big data these days, and for good reasons. Amongst them: Businesses crave ever more tim... 阅读全帖
 m******t发帖数: 273 12来自主题: JobHunting版 - how to do data fitting to find distribution (转载)【 以下文字转载自 Quant 讨论区 】 发信人: myregmit (myregmit), 信区: Quant 标 题: how to do data fitting to find distribution 发信站: BBS 未名空间站 (Sat Mar 15 11:02:05 2014, 美东) Hi, I need to do data fitting to find the distribution of a given data. I need to find the pdf funtion of the distribution. I can use data fitting functions in matlab and python. It looks like a truncated gamma. But, how to find the paramters of the distribution ? What if the data cannot fit the truncated gamma well ? The QQ-plot (qunatile-qua... 阅读全帖
 s***s发帖数: 1301 13来自主题: Database版 - 请教一个关于sql server distribution 的问题谢谢，我们就是publisher, distribution, subscriber分别在不同的server, distribution的server就用比较差点的配置。你说的临时的server是指distribution server还是指临时的subscriber server？ 一个publisher只能有一个distribution 的 ，用临时的distribution server 也是相当中断，然后还是要重新sync的 。 如果是指 subscriber端的server，可以临时顶替用下（数据不是最新的），不过离线upgrade distribtuion的话，再放回去，还是要重新resync 数据了。
 m******t发帖数: 273 14来自主题: Mathematics版 - how to do data fitting to find distribution (转载)【 以下文字转载自 Quant 讨论区 】 发信人: myregmit (myregmit), 信区: Quant 标 题: how to do data fitting to find distribution 发信站: BBS 未名空间站 (Sat Mar 15 11:02:05 2014, 美东) Hi, I need to do data fitting to find the distribution of a given data. I need to find the pdf funtion of the distribution. I can use data fitting functions in matlab and python. It looks like a truncated gamma. But, how to find the paramters of the distribution ? What if the data cannot fit the truncated gamma well ? The QQ-plot (qunatile-qua... 阅读全帖
 i*******1发帖数: 14 15来自主题: Quant版 - T-distribution属于哪类extreme value distribution?最近在看extreme value theory,里面提到三个distribution，i.e. Weibull, Gumbel, Frechet. T-distribution好像也属于extreme value distribution中的一种，不知道 属于三个中的哪个? 还有pareto distribution跟以上这些有什么关系？
 h******5发帖数: 58 16来自主题: Quant版 - log return distribution 选择现在给公司做一个paramatric model,就是extreme value的（跟VaR类似）。 现在找一 个比较好的distribution来fit股票、期货的distribution。 本来找了个meixner distribution，fit不错，但是感觉tail 太小了，结果比normal distribution还小。 版上有大牛知道其他还有什么distribution更加好的吗？或者推荐做法(i.e.monte carlo) 谢谢啦
 e****c发帖数: 183 17来自主题: Statistics版 - 急：一个normal distribution 加一个truncated normal distribu【 以下文字转载自 Mathematics 讨论区 】 发信人: ecosoc ( ), 信区: Mathematics 标 题: 一个normal distribution 加一个truncated normal distribution 是什么distribution？ 发信站: BBS 未名空间站 (Tue Mar 17 22:08:24 2009) 比如一个 N （0，alpha)。另一个N (x, beta), 但是这第二个distribution 只在s 和 t 之间。这两个distribution 加起来，是什么样子？
 f***a发帖数: 329 18来自主题: Statistics版 - sampling distribution 问题sampling distribution depends your underlying distribution and sampling statistic. if your underlying distribution is normal and your sampling statistic is sum of square, of course your sampling distribution is chi- square. Talking about sampling distribution only by itself is meaningless.
 y**********0发帖数: 425 19来自主题: Statistics版 - Multivariate distribution的问题看书的时候遇到一些multivariate normal distribution, multivariate t distribution, 特别是t-distribution，不知道那些公式是怎么推的，全是矩阵，有那 本书介绍这类问题吗，用矩阵分析的。我查了好多multivariate statistics analysis ，只是集中normal distribution。最好能推倒一下normal,t distribution的，用矩阵 的。
 l*********y发帖数: 142 20来自主题: Statistics版 - sample distribution的理解初学统计，对sample distribution的理解不到位。 请教如下一题， 从一堆球里选出100个球，已知这堆球中红球的比例是25％，请问选出的100个球中红球 超过40个的可能性有多大？ 我知道这题要用sample distribution来做。但是我总想用伯努力分布去解， 就是一项一项求B（x＝40）, B（x＝41）,B（x＝42），然后把他们加起来。 我感觉这样理解也是对的，但是我却把sample distribution 这个重要概念绕过了。 许多后面的讲解都直接建立在sample distribution之上，但我感觉sample distribution在这道题上可有可无。
 v********g发帖数: 250 21来自主题: Statistics版 - sample distribution的理解你好，首先，这是一个binomial和sampling distribution综合问题。 第一，大体上看，这是一个sampling distribution的问题。也就是说，从population 里randomly select samples。 所以，这是标准的sampling distribution的问题，但 关键在于，需要知道 population mu 和 variance. (x-u)/sqrt(variance) 就会是normal distribution了。 第二， 题目本身是 binomial的问题，也就说，红球出现follows binomial distribution. 而红球出现的 mean = n*p , variance= n*p*(1-p), 而这两个就是之 前要求出的 population mu 和 variance。 最后，本题目要求的是 P（X〉40），把X 换算成 Z, 这样就能得出最后的结果了。 希望对你有帮助。
 u******e发帖数: 60 22I have a score with missing value. The score is on a 0-70 scale and measured at 4 time points. The missing pattern is not monotonic. The score is not normally distributed in the sample. it is right skewed with a lot of subjects having score 0. Subjects with disease A are likely to have high score. The distribution of score is close to normal distribution when separating subjects with and without disease A. The purpose of the study is to assess relation between disease A and change of score durin... 阅读全帖
 m******t发帖数: 273 23来自主题: Statistics版 - how to do data fitting to find distribution (转载)【 以下文字转载自 Quant 讨论区 】 发信人: myregmit (myregmit), 信区: Quant 标 题: how to do data fitting to find distribution 发信站: BBS 未名空间站 (Sat Mar 15 11:02:05 2014, 美东) Hi, I need to do data fitting to find the distribution of a given data. I need to find the pdf funtion of the distribution. I can use data fitting functions in matlab and python. It looks like a truncated gamma. But, how to find the paramters of the distribution ? What if the data cannot fit the truncated gamma well ? The QQ-plot (qunatile-qua... 阅读全帖
 c******7发帖数: 439 24来自主题: Investment版 - realized loss可以从distribution扣除吗? (转载)【 以下文字转载自 TAX 讨论区 】 发信人: cobalt27 (27号元素), 信区: TAX 标 题: realized loss可以从distribution扣除吗? 发信站: BBS 未名空间站 (Wed Feb 1 13:05:45 2012, 美东) F1, NR 有mutual fund的distribution, 也有brokerage acct自己操作的realized loss. 我知道F1 loss不能抵税. 但总的从我distribution里面减掉这部分吧? 算我总共的财产性收入的盈利. 而且应该是只要是我名下的都算个总的, 即使是不同的broker分别报给IRS的也没有关系 求教, 谢谢! 另外从mutual fund那里面看来的只有distribution capital gain是要到realized时候才算吗?
 x*********n发帖数: 100 25来自主题: Investment版 - Mutual fund在distribution前卖掉是个好主意吗刚买的Mutual fund，vanguard small cap index。预计12月底有distribution. Turnover rate 是10%。根据今年的return 30%, 那应该是3%的distribution吧？ 就是说这3%我要交short term capital gain tax. 那如果我在distribution前几天卖掉，我就可以不用交这个distribution的税了。但是 我也得交这两个月涨的return的tax. 所以说到时候如果我的return是少于3%，我就该 卖掉，否则应该继续持有。是这样吗？
 n**a发帖数: 12 26来自主题: JobHunting版 - Amazon.com is looking for SDE's with Distributed SystemsHello, Amazon.com is looking for experienced engineers with Distributed and scalable systems background. Please send your resumes to n******[email protected] Many positions open, location- Seattle, WA Job description: SDE Amazon's New Ad Products group is looking for exceptional software engineers to build sophisticated distributed systems for next generation ad programs. The New Ad Products group was recently formed to build advertising systems to address new market segments. This new group within ... 阅读全帖
 f*******n发帖数: 12623 27来自主题: JobHunting版 - 给一个 [0, 1]区间上的 uniform distributionNo. You can't just use uniform distribution for r, because that way it will be too concentrated in the middle and too spread out at the edge. r needs to be weighted to the higher numbers. Specifically, the probability distribution of r needs to be P(r) = 2r. So that at r = 1, it is twice as likely as at r = 0.5. This is because dx dy = r dr dθ in polar coordinates. To do that you can use inverse transform sampling http://en.wikipedia.org/ wiki/Inverse_transform_sampling). The cumulative distrib... 阅读全帖
 l*******1发帖数: 147 28来自主题: JobHunting版 - 求AMAZON DISTRIBUTION CENTER内推各位好， 小弟刚刚商科毕业。最近看到AMAZON的在南方州的DISTRIBUTION CENTER有商科类职位 放出来。但是有A家的朋友说DISTRIBUTION CENTER的工作在INTERNAL REFERRAL SYSTEM 上看不到。 想请问各位是否有在DISTRIBUTION CENTER工作？或者是有哪位有权限REFER DISTRIBUTION CENTER的职位，能否帮忙推荐下。非常感谢。站短联系。 提前谢谢各位。
 m******t发帖数: 273 29来自主题: JobHunting版 - find distribution paramters only by data mean and std. dev. (转载)【 以下文字转载自 Statistics 讨论区 】 发信人: myregmit (myregmit), 信区: Statistics 标 题: find distribution paramters only by data mean and std. dev. 发信站: BBS 未名空间站 (Mon Mar 17 17:14:15 2014, 美东) I need to estimate a truncated gamma distribution paramters (shape , scale). But, I only know the data mean and std. dev. I do not know the dat set. Given the mean and std. dev. of a data set from a trucnated gamma distribution, how to find shape and scale of the distribution parameters ? I know MLE may be sueful for ... 阅读全帖
 v*********r发帖数: 184 30来自主题: TAX版 - 请问一下HSA的distribution问题请教一下： 我有个HSA account, W-2表格上box 12w上是$2150.02， 看了一下后面的说明，是 公司或者员工通过 cafeteria plan 交的存在HSA account的钱。 还有一张wells fargo（管HSA用的银行）给了一张statement,上面写着是issue as a statement for 1099-Q, 1099-SA,什么的，准备去向IRS要张1099-SA表格了，好像 还不能从网上下载。这张wells fargo statement上面box 1是gross distribution$ 1590.55,请问这个是什么意思，到底是去年存到HSA的\$ 2150.02我用了几百块钱看病后 ，剩下的1590.55还是我去年看病用了1590.55？ -- 我不记得看病拿药具体花了多少钱 了，distributuion code 是1. Form 8889, part II,里面14a： Total distributions you received in 2011 from all HSAs (see inst... 阅读全帖
 c*****n发帖数: 1877 31来自主题: CS版 - 请问distributed systems的master工作行情怎么样?LP得到了一个master位置: Distributed systems focuses on utilizing networks, from concurrent processes inside a computer to world-wide cooperating systems using the Internet. 具体的必修课有: 1. Open distribuert prosessering 2. Protocols and routing in the Internet 3. Programming heterogeneous multi-core architectures 4. Performance in distributed systems 5. Advanced topics in Distributed Systems 6. Advanced database systems 7. Seminar on Dependable and Adaptive Distributed Systems 我本人是学EE偏硬件的，可以说对这行了解比较少，所以来贵版发
 z****e发帖数: 54598 32来自主题: Programming版 - Flink Sparks Next Wave of Distributed Data ProcessingFebruary 22, 2015 Nicole Hemsoth art2 If you haven’t heard of Flink until now, get ready for the deluge. As one of a stream of Apache incubator-to-top-level projects turned commercial effort, the data processing engine’s promise is to deliver near-real time handling of data analytics in a much faster, more condensed, and memory- aware way than Hadoop or its in-memory predecessor, Spark, could do. What really captured our attention, however, was the claim by Data Artisans, the company behind Flin... 阅读全帖
 f*****l发帖数: 82 33来自主题: Computation版 - 问uncertainty是uniform distribution的monte carlo计算如果uncertainty是服从uniform distribution 的，有没有快速monte carlo方法，来 降低sample的size 还有就是如果我已经有了一组uniform distribution([-a, a]区间内均匀分布）对应的 monte carlo数据，有没有一种方法快速找出另外一组uniform distribution([-ra, ra ], r<1)对应的monte carlo数据，或者说利用reference uniform distribution产生的 monte carlo数据generate某一个performance的expectation value或者probability。 谢谢
 v*c发帖数: 42 34来自主题: Mathematics版 - 问一个asymptotic distribution的问题 (转载)【 以下文字转载自 Statistics 讨论区 】 发信人: vic (红尘中的精灵), 信区: Statistics 标 题: 问一个asymptotic distribution的问题 发信站: BBS 未名空间站 (Wed Aug 22 23:12:07 2007) 已知cdf(cumulative distribution funciton)得asymptotic distribution. 能够知道 pdf(probability density function)的asymptotic distribution 是什么么？用delta method好像这里不行。 That is, we know sqrt(n)[\hat_{F}(Y)-F(Y)]->N(0,sigma) what is sqrt(n)[\hat_{f}(Y)-f(Y)]->? F is cdf of random variable Y. f is pdf of random variable Y. \hat_{F}(Y) is the empirical estimator of F(Y). And \
 m******t发帖数: 273 35来自主题: Mathematics版 - find distribution paramters only by data mean and std. dev. (转载)【 以下文字转载自 Statistics 讨论区 】 发信人: myregmit (myregmit), 信区: Statistics 标 题: find distribution paramters only by data mean and std. dev. 发信站: BBS 未名空间站 (Mon Mar 17 17:14:15 2014, 美东) I need to estimate a truncated gamma distribution paramters (shape , scale). But, I only know the data mean and std. dev. I do not know the dat set. Given the mean and std. dev. of a data set from a trucnated gamma distribution, how to find shape and scale of the distribution parameters ? I know MLE may be sueful for ... 阅读全帖
 K*****Y发帖数: 629 36来自主题: Quant版 - 问一个sampling from multivariate distribution 的问题If the marginal distribution does not belong to the family of elliptical distribution, then correlation is not a good measure of dependence, copula is more general here. Your joint distribution will take the form: F(x,y) = C(F1(x),F2(y),theta). Where F1,F2 are your marginal distributions, while C is the copula function. You need to estimate the unknown parameter theta though. If you want to stick to the correlation framework, another simpler approach would be like this: Simulate (Z1,Z2), w
 m******t发帖数: 273 37来自主题: Quant版 - how to do data fitting to find distributionHi, I need to do data fitting to find the distribution of a given data. I need to find the pdf funtion of the distribution. I can use data fitting functions in matlab and python. It looks like a truncated gamma. But, how to find the paramters of the distribution ? What if the data cannot fit the truncated gamma well ? The QQ-plot (qunatile-quantile) show that it is not a good fit for truncated gamma. How to find the distribution parameters such as alpha (shape), beta (scale) for the truncated g... 阅读全帖
 m******t发帖数: 273 38【 以下文字转载自 Statistics 讨论区 】 发信人: myregmit (myregmit), 信区: Statistics 标 题: find distribution paramters only by data mean and std. dev. 发信站: BBS 未名空间站 (Mon Mar 17 17:14:15 2014, 美东) I need to estimate a truncated gamma distribution paramters (shape , scale). But, I only know the data mean and std. dev. I do not know the dat set. Given the mean and std. dev. of a data set from a trucnated gamma distribution, how to find shape and scale of the distribution parameters ? I know MLE may be sueful for ... 阅读全帖
 R*******c发帖数: 249 39we know that normal distribution is usually chosen as the prior distribution , are there any other common prior distributions so that we can have a closed form for the posterior distribution?
 z*********o发帖数: 541 40来自主题: Statistics版 - how to find the limiting distribution1. let Yn denote the nth order statistic of a random sample from a distribution of the continuous type that has cdf F(x) and pdf f(x)=F'(x). Find the limiting distribution of Zn=n[1-F(Yn)] 2.Let Xn have a gamma distribution with parameter α=n and β, where β is not a function of n. Let Yn=Xn/n. Find the limiting distribution of Yn. thanks
 B*********L发帖数: 700 41来自主题: Statistics版 - 有数据，想知道是什么distribution，参数是什么，有免费工具吗？多谢，我Plot了一下，大概是 log-normal distribution， 其实俺只听说个两种 distribution：normal distribution和log-normal distribution。要我不知道的怎么办 ？难道没有什么软件读一下，直接把density function告诉我吗？
 f***a发帖数: 329 42来自主题: Statistics版 - 根据一个已知的数据集，估算这个数据的probability distribution 一般用那些方法？其实我觉得第一步先画个histogram看看形状，然后猜测几个candidate distributions ，再去estimate their parameters，然后再验证数据是不是fit。 至于如何验证empirical distribution和candidate distribution是不是fit的方法， 我胡乱说几个： 一当然是画图比较density function; 二可以有计算PIT (Probability integral transform)，这个主要是看 underdispersion or overdispersion的 三是可以计算EMD (Earth mover's distance)，这个是比较两个distributions之间“ 距离”的。
 y*****w发帖数: 1350 43来自主题: Statistics版 - Binomial distribution: what's p exactly?In wiki, the binomial distribution is explained as "the discrete probability distribution of the number of successes in a sequence of n independent yes/ no experiments, each of which yields success with probability p." I am uncertain how to interpret that p. Again in wiki, it says "flip a coin three times and count the number of heads. The distribution of this random number is a binomial distribution with n = 3 and p = 1/2." However, I saw some other examples that use an empirical group percenta
 y*****w发帖数: 1350 44来自主题: Statistics版 - test count data distribution in SASIf your count data does not include zero values, you can use PROC UNIVARIATE with the HISTOGRAM statement to get goodness-of-fit test statistics for several distributions, however those distributions do not include NB. http://support.sas.com/documentation/cdl/en/procstat/63104/HTML I have recently run a project in which I had to choose a best distribution for my non-zero historical count data for the purpose of sample size calculation. I applied the HISTOGRAM statement to compare GAMMA, LOGNORMA... 阅读全帖
 c**d发帖数: 104 45来自主题: Statistics版 - sample distribution的理解population: Bernoulli distribution(p) If x1, x2,x3, Xn are independent, identically distributed (i.i.d.) random variables, all Bernoulli distributed with success probability p, then sample dist: Binomial distribution(n,p)
 y*****w发帖数: 1350 46来自主题: Statistics版 - Gamma distribution for power analysis,请大拿指点Because as I mentioned, SAS PROC POWER with the TWOSAMPLEWILCOXON statement , which I used for the sample size calculation, has no NEGB option. Actually I found I don't need PROC GENMOD in this context, because I found that lognormal distribution better fits my data than Gamma distribution, whereas PROC GENMOD does not have the lognormal option as a distribution. I found the following SAS example using PROC UNIVARIATE very useful in that it provides simple and straightforward statistics and gra... 阅读全帖
 z*****3发帖数: 17 47来自主题: Statistics版 - 如何比较两组posterior distribution是否有显著差异请问应该如何比较两个parameter vector的posterior distribution，parameter之间 可能有correlation 数据来自于两个condition（cancer v.s normal），两个condition是independent的。 我想对两个condition中每一个基因进行比较（每个condition的数据由N行组成，每一 行是一个基因，N行数据，N个基因）。我用MCMC求出了每一个基因（每一行数据）的某 参数的posterior distribution。也就是说，我现在有N个theta_i的posterior。 我打 算从N个theta中挑出m个和另外一个condition中的m个theta比较，这m个theta是有 correlation的。请问我应该怎么判断第一个condition中m个theta的multivariate distribution 是不是和另一个condition中相对应的m个 theta的multivariate distribution 有显著差异？ 谢谢！
 r*******7发帖数: 1811 48来自主题: Statistics版 - 发包子求教! 两个uniform （0,1）distribution的joint distribution怎么求？我的问题是想给simulate出来的multi uniform distribution 画一个3D的图。因为只 用到2个variables，所以需要求出2个uniform distribution的 joint distribution， 假设这两个uniform都是0,1的，cor为0.5。该怎么求呢？ 跪谢~
 v*******e发帖数: 11604 49来自主题: Statistics版 - 发包子求教! 两个uniform （0,1）distribution的joint distribution怎么求？我觉得楼主头脑里面一团浆糊，对多维随机变量非常不理解。题目都没提对。已经有 multi uniform distribution了，画图就行了，假设二维，则分布是一个水平面。 现在楼主又说“假设这两个uniform都是0,1的，cor为0.5”，那么这个joint distribution不是uniform的，称之为multi uniform distribution又不对。 或者楼主想从两个uniform分布，以及他们的cor来推出joint分布？可惜这样的分布是 推不出来的。
 发帖数: 1 50来自主题: Military版 - 等我有一天发distribution的时候Distribution also refers to a company's payment of stock, cash or physical products to its shareholders. Mutual fund companies give earnings and other payouts to shareholders as a distribution. 等我有一天发distribution的时候，我就很厉害了。。吧？
 1 2 3 4 5 6 7 8 9 10 下页 末页 (共10页)