question stringlengths 37 38.8k | group_id stringlengths 2 6 | sentence_embeddings listlengths 768 768 |
|---|---|---|
<p>Let $X_1, X_2, ..., X_n$ be an iid random sample from a Poisson$(\lambda)$ distribution:</p>
<p>a) find the UMVUE of $\theta$ = $\lambda^k$ for $k > 0$ a known integer</p>
<p>b) find the UMVUE of $\tau = e^{-\lambda} = \mathbb{P}(X = 0)$.</p>
<p><strong>Edit:</strong> I have found that $T = \sum X_i$ is a co... | g7677 | [
0.03154056519269943,
-0.0027206114027649164,
-0.031256791204214096,
-0.03133990615606308,
-0.016449064016342163,
-0.03200605884194374,
-0.020884789526462555,
0.015104942955076694,
-0.03372979909181595,
-0.018302520737051964,
-0.04610771685838699,
0.02239207550883293,
-0.016038740053772926,
... |
<p>Which problems are best solved using which kernels and why?</p>
<p>Can you give a simple toy problem that isn't linearly separable in input space but is linearly separable in feature space, using an RBF kernel? A polynomial kernel?</p> | g65203 | [
0.033781372010707855,
0.035755474120378494,
0.020391644909977913,
-0.0071791247464716434,
0.005558827426284552,
-0.06555292010307312,
0.04232240468263626,
-0.024598628282546997,
-0.017708923667669296,
0.008482279255986214,
-0.01726147159934044,
0.0019850609824061394,
-0.015841877087950706,
... |
<p>I have counts of plants from different sites over a number of years. In each census year, all sites were surveyed, but the gaps between census years vary (between 1 and 4 years between consecutive surveys). I would like to use a GEE to account for the correlation structure of the data (but really, my purpose is just... | g23697 | [
0.0010591187747195363,
-0.02195892482995987,
-0.009635417722165585,
-0.05962815880775452,
0.017661014571785927,
0.04711754247546196,
0.05430365353822708,
-0.006724928505718708,
-0.025742674246430397,
-0.03471485152840614,
0.023729629814624786,
-0.021285032853484154,
-0.003332616062834859,
... |
<p>Let $X_1,X_2,\ldots, X_{n_1}$ be IID with PDF $f(x-\theta) $, for $-\infty<x<\infty$ and $-\infty<\theta<\infty$. Denote the CDF of $X_i$ by $F(x-\theta)$.
Let $Z_1,Z_2, \ldots, Z_{n_2}$ denote the censored observations. For these observations we only know that $Z_j >a $ for some $a$ that is known an... | g65204 | [
-0.005484757479280233,
-0.014403528533875942,
-0.014768021181225777,
0.01521865464746952,
0.015975914895534515,
0.020751729607582092,
0.045916229486465454,
0.012469322420656681,
-0.03320721536874771,
-0.011227816343307495,
-0.010804278776049614,
0.01883699558675289,
0.03609742596745491,
0.... |
<p>I have little background in statistics. For a dozen items, I have vectors of ratings for these items.</p>
<p>I have calculated the variance, and Pearson correlation for these items (using numpy). Now I would like to compare them.</p>
<p>My adviser asked me to see if the differences in variance and correlation were... | g23699 | [
-0.004232130013406277,
0.011479562148451805,
-0.036018095910549164,
-0.08266394585371017,
0.022376297041773796,
-0.03689233958721161,
-0.004107040353119373,
0.014656771905720234,
-0.02375463768839836,
-0.05251825228333473,
0.02816585823893547,
0.0065407403744757175,
0.040756456553936005,
0... |
<p>In the compressed sensing (CS) framework an incoherence property $\mu$ is used to quantify the correlation between a sensing matrix $\Phi$ and a representation matrix $\Psi$. This incoherence relationship is given by</p>
<p><img src="http://i.stack.imgur.com/gCcHJ.jpg" alt="enter image description here"></p>
<p>w... | g65205 | [
-0.019191287457942963,
-0.033701341599226,
-0.014002283103764057,
-0.07728595286607742,
0.02399551123380661,
-0.04102746769785881,
-0.02211923524737358,
0.01686283014714718,
-0.01204171497374773,
-0.016422998160123825,
0.010264532640576363,
-0.020041288807988167,
-0.019315406680107117,
-0.... |
<p>First time poster, long time desperate reader. This place has been so helpful that I can usually find that someone has had the same problem as myself and had it answered here. However, I haven't found an answer to my problem below in a way that I understand.</p>
<p>I am having trouble finding consistent z-scores wi... | g65206 | [
0.014606919139623642,
-0.055025581270456314,
-0.017270784825086594,
-0.019612489268183708,
0.03274345025420189,
-0.0014577509136870503,
0.028139609843492508,
-0.05068998411297798,
-0.03244491666555405,
-0.013227134011685848,
-0.018555939197540283,
0.011915978044271469,
0.040605004876852036,
... |
<p>I am trying to model votes by individuals on a number of bills over time using bill-specific characteristics as explanatory variables. Imagine that the same bill is offered to them albeit with minor changes from year to year. <strong>I want to determine what sort of changes in text of the bill will make individuals ... | g65207 | [
-0.01420254074037075,
-0.013012891635298729,
0.013015025295317173,
-0.027010876685380936,
-0.01032876968383789,
-0.004090459551662207,
0.029366351664066315,
0.02190571092069149,
-0.003048665588721633,
-0.0006950207753106952,
-0.03688818961381912,
0.03472738340497017,
0.002221564296633005,
... |
<p>Let $X = N(0,\frac{1}{\alpha})$, $Y = 2X + 8 + N_{y}$, and $N_{y}$ be a noise $N_{y} = N(0,1)$. Then, $P(y|x) = \frac{1}{\sqrt{2\pi}}exp\{ -\frac{1}{2}(y - 2x - 8)^{2} \}$
and $P(x) = \sqrt{\frac{\alpha}{2\pi}}exp\{-\frac{\alpha x^{2}}{2}\} $.</p>
<p>The mean vector is:</p>
<p>$$\mathbf{\mu} = \left( \begin{arr... | g65208 | [
0.0054045747965574265,
-0.02944236621260643,
-0.027507491409778595,
-0.02368101291358471,
0.07615182548761368,
0.001689293421804905,
0.021120456978678703,
-0.002981338882818818,
-0.02308574691414833,
-0.009463759139180183,
-0.05394595488905907,
0.10607276111841202,
-0.015616991557180882,
0... |
<p>In my attempts to fight spreadsheet mayhem, I am often evangelical in pushing for more robust tools such as true statistics software (R, Stata, and the like). Recently, I was challenged on this view by someone who stated flat out that they simply will not learn to program. I would like to provide them with data an... | g43638 | [
0.022711819037795067,
0.016461357474327087,
-0.007546938490122557,
-0.012864381074905396,
-0.06511346995830536,
-0.035377051681280136,
0.046111635863780975,
-0.045443955808877945,
0.007585669867694378,
-0.10185171663761139,
0.02256772853434086,
-0.012259413488209248,
0.05318758264183998,
-... |
<p>The objective of this research was to investigate the long-term effects of irrigation with treated waste water on some chemical soil properties. </p>
<p>The investigation was carried out by comparison of soil properties in two different fields: one irrigated with the effluent from Parkan Waste water Treatment Plant... | g65209 | [
-0.0030374478083103895,
-0.02152610383927822,
-0.0035774745047092438,
-0.031054165214300156,
-0.002882439410313964,
0.024504272267222404,
0.014111971482634544,
-0.013553331606090069,
-0.019152527675032616,
-0.021220674738287926,
-0.005737626925110817,
0.032010167837142944,
0.0401784181594848... |
<p><strong>Problem background:</strong> As part of my research, I have written two algorithms that can select a set of features from a data set (gene expression data from cancer patients). These features are then tested to see how well they can classify an unseen sample as either cancer or non-cancer. For each run of... | g65210 | [
0.011531814932823181,
-0.06062813475728035,
0.012911141850054264,
-0.01748751290142536,
0.004856457468122244,
-0.01171579584479332,
-0.026674913242459297,
0.02584180235862732,
-0.05625753477215767,
0.043328430503606796,
0.0227104052901268,
0.05359477922320366,
0.020615048706531525,
0.01602... |
<p>Say I have the following data, </p>
<ul>
<li>% students below average in math: S1</li>
<li>% of students at proficient level in math: S2</li>
<li>% of students at above proficient level: S3</li>
</ul>
<p>S1 + S2 + S3 = 100%</p>
<p>If I have this distribution across multiple classes and multiple years, how can I d... | g65211 | [
0.006797293201088905,
-0.045586876571178436,
-0.029020775109529495,
-0.021173782646656036,
-0.030711188912391663,
0.0015234907623380423,
0.010867341421544552,
0.02977399341762066,
-0.010785750113427639,
-0.0007677159737795591,
0.0018737231148406863,
0.025648608803749084,
0.05569019913673401,... |
<p>R Language what is diffrence between functions rnorm and runif </p> | g65212 | [
-0.011572697199881077,
-0.0545223206281662,
0.0018502047751098871,
0.011934294365346432,
0.035303909331560135,
-0.030181661248207092,
0.04109416529536247,
-0.021631387993693352,
-0.03701218217611313,
-0.059792786836624146,
-0.06028109788894653,
0.035414133220911026,
-0.0006645992980338633,
... |
<p>I am starting to use GMM estimation of dynamic panels with fixed-effects in R, but couldn't find proper information on the differences between "two-ways" and "individual" effects. Both can be easily estimated in R, but I couldn't get the right conceptual difference. Any help or indication here will be most welcome.<... | g65213 | [
0.00815372634679079,
-0.04380716010928154,
0.012283981777727604,
0.020320460200309753,
-0.014612563885748386,
-0.012461517937481403,
0.05847597122192383,
0.0006234990432858467,
-0.07417882233858109,
-0.03149617463350296,
0.01180149707943201,
0.03643020987510681,
-0.01077452301979065,
0.077... |
<p>I am getting an unexpected error from running predict variance after mgarch dcc command. I am using Stata 13 for Windows. I tried to find the dynamic correlation between two time series by using mgarch dcc step by step.</p>
<pre><code>arch var1, arch(1) garch(1)
predict res1, residual
predict h1, var
gen std1=sqrt(... | g65214 | [
0.03434322401881218,
-0.03713817521929741,
0.012925360351800919,
-0.05505586043000221,
-0.024144383147358894,
-0.028283825144171715,
0.07778968662023544,
0.025483185425400734,
-0.03644050657749176,
-0.0593901127576828,
-0.010899947956204414,
0.06496080756187439,
0.02155117318034172,
-0.022... |
<p>Given a i.i.d sample $X_{1},..,X_{n}$ of bernoulli random variables test 2 hypotheses $H_{0}:p=2/3$ and $H_{1}:p=1/3$. Bayesian prior is $\pi(2/3)=1/3$ and $\pi(1/3)=2/3$. Find the bayesian criterion for acceptng $H_{0}$, find the bayesian mean square error for the test and for $n=8$ compute this mean square error u... | g65215 | [
0.026157230138778687,
-0.012399720028042793,
-0.008387740701436996,
-0.028462741523981094,
-0.0566130205988884,
0.0056488956324756145,
0.009699336253106594,
-0.015346884727478027,
-0.02218647301197052,
-0.01081631239503622,
0.00819967407733202,
0.03632572293281555,
-0.018687497824430466,
0... |
<p>On the Probability chapter of a 1995 mathematical statistical book I am reviewing I have found the following exercise: </p>
<blockquote>
<p>Let A and B be arbitrary events. Let C be the event that either A occurs or B occurs, but not both. Express C in terms of A and B using any of the basic operations of union, ... | g65216 | [
0.044245362281799316,
-0.005115298088639975,
-0.0024267290718853474,
-0.02085224725306034,
0.022862397134304047,
-0.018060902133584023,
0.07273948937654495,
0.05690576881170273,
-0.01789538562297821,
0.002577422885224223,
-0.003587836865335703,
0.017557471990585327,
0.017744679003953934,
0... |
<p>I'm interested in calculating the log probability of data drawn from a Dirichlet distribution. In particular, I'm interested in calculations that are stable in high dimensions, perhaps 1000 dimensions or more.</p>
<p>I've tried to use the "dirichlet_logProb.m" function from Tom Minka's fastfit toolbox: <a href="htt... | g65217 | [
0.0012344933347776532,
0.023927774280309677,
0.017959196120500565,
-0.052539560943841934,
-0.038673873990774155,
0.029039470478892326,
0.012809770181775093,
0.030522091314196587,
-0.07641994953155518,
-0.042390916496515274,
-0.05951528996229172,
-0.012217548675835133,
0.10878432542085648,
... |
<p>Today I was thinking about how one would treat what I'm guessing must come up constantly in statistics so apologies if it's trivial.</p>
<p>Some statistics such are easy to forecast, such as length, thanks to their normalish properties. But what if I'm interested in forecasting something like the number of children... | g65218 | [
0.021858997642993927,
0.048620741814374924,
0.007582542952150106,
-0.019005613401532173,
-0.07242460548877716,
-0.030748624354600906,
-0.056382350623607635,
0.03974989429116249,
0.0039014997892081738,
-0.06525862216949463,
0.011351237073540688,
-0.035586003214120865,
0.04926062002778053,
0... |
<p>The usual derivations by physicists of the Bell-CHSH inequalities as a limit imposed on any possible local hidden variables description of quantum systems seems so sloppy, that I'm tempted to ask you statisticians if there is a rigorous mathematical derivation of these results. Also, what would be a proper statistic... | g23708 | [
-0.003335363231599331,
0.020587118342518806,
0.0133960647508502,
-0.028812896460294724,
-0.003986296709626913,
-0.004648240283131599,
0.008052961900830269,
0.036438364535570145,
0.020316025242209435,
-0.020721161738038063,
-0.08308354020118713,
0.040539417415857315,
-0.03036700375378132,
0... |
<p>Assuming a class is well described with a normal distribution of <em>u</em> and <em>s</em>, is it reasonable to calculate the probability of membership as: </p>
<p>$Pr(x)=Pr(|x-u|)=2.0*\text{cdf}(|x-u|,s)$?</p>
<p>I've briefly researched unary classification mechanisms, but I believe them to be out of scope since ... | g16869 | [
-0.015283389948308468,
0.03387954458594322,
0.00524147879332304,
-0.029963236302137375,
-0.014855846762657166,
-0.019257139414548874,
0.04025906324386597,
0.07405770570039749,
-0.0019386770436540246,
-0.012439622543752193,
0.020854761824011803,
0.054851047694683075,
0.05067878216505051,
-0... |
<p>I've been having a difficult time looking for a solution to identifying the comparative sentence. I like to extract the first noun (NP1) or second noun (NP2) from the given sentence fragment with comparaed word. First, I want to extract the comparative sentence, then I want to extract the entity(NP1).</p> | g23710 | [
0.04786662384867668,
-0.04894334822893143,
0.01723325438797474,
-0.0525335855782032,
0.033174578100442886,
-0.053556639701128006,
-0.015895670279860497,
0.051168330013751984,
-0.0030906989704817533,
-0.016860470175743103,
0.03688669949769974,
-0.01204645074903965,
-0.017466461285948753,
0.... |
<p>$\newcommand{\var}{\mathrm{Var}}$In my textbook I am studying about heteroskedasticity in a linear regression model, and for doing the hypothesis test, it says our hypothesis is: $H_0: \var(u|x_1,x_2,...,x_k)=\sigma ^2$, however than it says:</p>
<blockquote>
<p>Because we are assuming that $u$ has a zero conditi... | g10801 | [
0.051767461001873016,
-0.0012027506018057466,
-0.017926836386322975,
0.02703256718814373,
0.04451874643564224,
-0.03321293741464615,
0.0012065926566720009,
0.027062194421887398,
-0.035201385617256165,
-0.06396624445915222,
0.015357689931988716,
0.09240759164094925,
0.036500245332717896,
0.... |
<p>Suppose we are using logistic regression on a binary outcome variable $Y$ with two continuous predictors $X_1$ and $X_2$. Suppose the observation $Y = 1, X_1 = 10, X_2 = 15$ occurs 1000 times. In SAS, how would you account for this frequency in the regression without having to manually type the observation 1000 time... | g23712 | [
-0.019012397155165672,
-0.011034783907234669,
0.01190868578851223,
-0.007844014093279839,
0.05707881227135658,
-0.0587528757750988,
0.01757877692580223,
0.05314432457089424,
-0.04359137639403343,
-0.037305109202861786,
0.024703536182641983,
-0.00536589790135622,
0.039473339915275574,
0.023... |
<p>I have two datasets describing real-estate properties</p>
<p>Dataset 1 describes building characteristics; it includes the location of the entrance to the building along with building descriptions and demographics;</p>
<pre><code>Longitude Latitude Quality Index Age of building (years) (.....hun... | g23713 | [
0.04626299813389778,
-0.014087170362472534,
-0.015320850536227226,
-0.050632547587156296,
0.02776554599404335,
-0.004449934232980013,
0.013703197240829468,
0.07884418964385986,
-0.05247367173433304,
0.02829582430422306,
0.016884949058294296,
0.04275292530655861,
0.044535327702760696,
-0.01... |
<p>In calculating the expectation of a discrete random variable $X$, we not only require that $\Sigma x_iP(X=x_i)$ converges, but also converges absolutely. I understand this requirement as probably stemming from the fact that a rearrangement of non-absolutely-convergent countably-infinite sum can have a different sum.... | g65219 | [
-0.03868865221738815,
0.036696791648864746,
-0.008091275580227375,
-0.017549147829413414,
-0.07670631259679794,
0.0007443362846970558,
-0.015454269014298916,
-0.002009471645578742,
-0.05889006331562996,
-0.0001274250535061583,
-0.05020706728100777,
0.020359808579087257,
-0.03488369286060333,... |
<p>I am trying to find the correlation or association between a categorical variable - classes from 1 -4 from a GIS (<em>geographic information system</em>) classification - and a continuous variable with values between 0 and 9. What would be the best test to use for this? </p> | g65220 | [
0.043646685779094696,
-0.005985098425298929,
-0.0026219200808554888,
-0.04661877080798149,
-0.012508070096373558,
0.008633535355329514,
0.00885822158306837,
0.015705786645412445,
-0.024978555738925934,
-0.036193717271089554,
0.04432820528745651,
0.031508054584264755,
0.03437016159296036,
0... |
<p>There are 100 people in a room.
What are the odds at least 1 person is born in January?</p>
<p>What is the best way to calculate this?</p>
<p>I used Binomial Distribution.</p>
<p>$E(x) = np = 100 \frac{1}{12} = 8.3$</p>
<p>$std.dev. = \sqrt{npq} = 2.76$</p>
<p>$Z(\text{1 person}) = (1 - 8.3) / 2.76 = -2.64$</p>... | g23717 | [
0.03565182909369469,
0.0038032822776585817,
0.000726644357200712,
0.06699097156524658,
-0.019237494096159935,
0.08442751318216324,
0.0453786700963974,
0.023080335929989815,
-0.02148306742310524,
-0.05066166818141937,
-0.019976533949375153,
0.008657259866595268,
0.035524267703294754,
-0.000... |
<p>Could anyone explain in plain English what the difference is between Scott's and Silverman's rules of thumb for bandwidth selection?
Specifically, <strong>when</strong> is one better than the other? Is it related to the underlying distribution? Number of samples?</p>
<p>P.S. I am referring to <a href="https://githu... | g65221 | [
0.06965406984090805,
0.03888513892889023,
-0.004088832996785641,
-0.029866132885217667,
-0.0033117339480668306,
-0.031206756830215454,
0.040074750781059265,
-0.013162750750780106,
0.032106854021549225,
-0.004764438606798649,
0.029395952820777893,
-0.03615317493677139,
0.01224659662693739,
... |
<p>We want to work out a value for "Average time in service" for our users.</p>
<p>However, as we have many subscribers still active, how can we do that? If we just look at average time of deactivated subscribers, that won't show the picture.</p>
<p>Is there some "correct" way to do this? We know our churn rate by m... | g65222 | [
-0.039665646851062775,
0.005400672554969788,
-0.010478317737579346,
-0.059161800891160965,
-0.03136379271745682,
-0.08437677472829819,
0.04281260818243027,
-0.003558654570952058,
-0.009585084393620491,
0.03783095255494118,
-0.01789459027349949,
0.041638560593128204,
0.05507905036211014,
0.... |
<p>I'm fitting a logistic regression to a simple two-feature dataset. The feature values range from about 1 to 100. When I scale the features (using scikit-learn StandardScaler), the in-sample performance improves significantly, but the out of sample performance drops. Why would feature scaling cause overfitting?</p> | g65223 | [
0.03429681807756424,
0.021020082756876945,
0.013081517070531845,
-0.04072318226099014,
0.052145157009363174,
-0.012182347476482391,
0.0017467665020376444,
0.03131246939301491,
-0.09495747089385986,
-0.0038694178219884634,
0.0007884305668994784,
0.008529183454811573,
0.039555612951517105,
0... |
<p>Car analogy:</p>
<p>Assume the traffic (number of cars per hour) on a road has a Poisson distribution, and the time between cars has the matching exponential distribution. If the chance of each car being red is independent from both time and the color of other cars, will the number of red cars per hour also have a ... | g398 | [
0.036239687353372574,
0.03081660531461239,
-0.007588519249111414,
-0.05781884491443634,
0.03978034481406212,
-0.045421186834573746,
-0.011863122694194317,
0.0018516338896006346,
0.003370406571775675,
0.03164231777191162,
-0.019736113026738167,
-0.05157465115189552,
0.009755929931998253,
-0... |
<p>I have two classifiers</p>
<ul>
<li>A: naive Bayesian network</li>
<li>B: tree (singly-connected) Bayesian network</li>
</ul>
<p>In terms of accuracy and other measures, A performs comparatively worse than B. However, when I use the R packages ROCR and AUC to perform ROC analysis, it turns out that the AUC for A i... | g65224 | [
0.04557618871331215,
-0.07870830595493317,
-0.02131345495581627,
-0.031166305765509605,
0.08216236531734467,
-0.059674929827451706,
0.04590008035302162,
-0.024174539372324944,
-0.022023692727088928,
-0.01688101887702942,
0.017249131575226784,
0.06720652431249619,
0.06205606088042259,
0.024... |
<p>I have a large dataset I am trying to do cluster analysis using SOM. The dataset is huge (~ billions of records) and I am not sure what the number of neurons should be or the SOM grid size to start with. </p>
<p>Any pointers to some material that talks about estimating the number of neurons and grid size would be g... | g23721 | [
-0.0018770125461742282,
0.07853806763887405,
-0.002987904706969857,
-0.07091355323791504,
0.006465100217610598,
-0.09133172035217285,
0.030985957011580467,
0.11440184712409973,
-0.04088611900806427,
0.045086443424224854,
0.010460318066179752,
0.03655228391289711,
0.04646322503685951,
0.024... |
<p>I am learning about Generalized Linear Models and the use of the R statistical package, but, unfortunately, I am unable to understand some fundamental concepts.</p>
<p>I am trying to develop a GLM - Poisson model but using a specific log link function. The function is of the form</p>
<p>$$\ln(E(y_i)) = \ln(\beta_1... | g65225 | [
0.01037672907114029,
-0.0138545585796237,
-0.029048258438706398,
-0.027251049876213074,
0.022365525364875793,
-0.010541551746428013,
0.02562003582715988,
-0.002831732388585806,
-0.06587003916501999,
-0.03956923633813858,
-0.06927455216646194,
0.03209470957517624,
0.032739121466875076,
-0.0... |
<p>I am trying to find references about (early, as in pre-2000, but i would really love something pre-1990) statistical language models in word completion (like T-9, or Google's search autocomplete), but find it hard to find such papers. The best match i found was using statistical models to support semi-automated tran... | g65226 | [
0.03573772311210632,
0.00577690452337265,
0.015129314735531807,
-0.06767050921916962,
-0.059727203100919724,
-0.047793567180633545,
0.03326290100812912,
0.04809548705816269,
-0.03015674278140068,
0.03780999034643173,
-0.013458048924803734,
-0.08598345518112183,
0.07584796845912933,
-0.0123... |
<p>I've been trying to learn about effect size in relation to linear regression and am wondering how to implement it in R. Sure, I have p-values and they indicate how "predictive" the explanatory variable is. However, for each variable in a linear model, I was wondering how to compute a standardized score for how much ... | g65227 | [
-0.0008981606224551797,
-0.015179839916527271,
-0.004603905603289604,
-0.05550149455666542,
-0.03832145407795906,
-0.0690532699227333,
0.008949607610702515,
0.06036004424095154,
-0.03063693456351757,
-0.04646424949169159,
-0.013866828754544258,
0.03679700568318367,
0.04916859790682793,
0.0... |
<p>I am currently working on my dissertation project where my data are essentially all dummies. From my dependent to my independent variables, everything is a dummy variable (0,1), at least for the preliminary model. The data are cross-sectional. </p>
<p>I was wondering what the best model to use would be. I have deci... | g65228 | [
0.014986863359808922,
-0.016675030812621117,
-0.0063303508795797825,
-0.035934928804636,
-0.045023735612630844,
-0.013380799442529678,
-0.004280958324670792,
-0.03937260061502457,
-0.031362928450107574,
-0.01396484486758709,
0.027168234810233116,
0.00019974895985797048,
0.04806066304445267,
... |
<p>My problem is that I have different points (4) in a 3D space each point allows to a class. Other 4 points in a 3D space each point allows to a class. I want to know which of these spaces is more sparse.</p>
<p>My question are:</p>
<ol>
<li><p>How I can to get the area of svm with 2-dimensional features?</p></li>
<... | g65229 | [
0.01146639883518219,
0.02293216995894909,
-0.007961183786392212,
0.006941183935850859,
-0.004080743528902531,
0.005184462293982506,
0.0013238586252555251,
0.027029940858483315,
-0.024024277925491333,
-0.01307453028857708,
0.004665812477469444,
0.038089100271463394,
0.07527056336402893,
0.0... |
<p>I've recently encountered the bivariate Poisson distribution, but I'm a little confused as to how it can be derived.</p>
<p>The distribution is given by:</p>
<p>$P(X = x, Y = y) = e^{-(\theta_{1}+\theta_{2}+\theta_{0})} \displaystyle\frac{\theta_{1}^{x}}{x!}\frac{\theta_{2}^{y}}{y!} \sum_{i=0}^{min(x,y)}\binom{x}{... | g65230 | [
0.016767438501119614,
-0.024594204500317574,
-0.018294284120202065,
-0.052622389048337936,
0.012269885279238224,
-0.018138179555535316,
0.030705327168107033,
-0.0009472888195887208,
0.003707868978381157,
-0.04260387644171715,
-0.03193533793091774,
0.015201817266643047,
-0.007649068720638752,... |
<p>When running Weka on my dataset, in the results printout I get the following rows:</p>
<pre><code>Class complexity | order 0 44138.7117 bits 8.9205 bits/instance
Class complexity | scheme 46697.7417 bits 9.4377 bits/instance
Complexity improvement (Sf) -2559.03 bits -0.... | g27952 | [
-0.03687771409749985,
-0.02121523953974247,
-0.024639327079057693,
-0.04264942184090614,
0.020174190402030945,
-0.04262518882751465,
0.05236095190048218,
0.022362399846315384,
-0.0558723546564579,
-0.062334589660167694,
-0.04396281763911247,
0.05797900632023811,
0.03567739576101303,
0.0146... |
<p>I am performing a binary logistic regression. I have developed a simple model which I am testing using the SPSS application. This first determines the predictive ability of a baseline model without using the independent variables and then adds in the variables to eatablish if the "new" model increases the % predicti... | g65231 | [
0.012461893260478973,
-0.03008813038468361,
0.02092656120657921,
-0.0121494485065341,
0.04498763754963875,
-0.015082568861544132,
0.009786982089281082,
0.04810089245438576,
-0.007828797213733196,
-0.06970775127410889,
0.0007371824467554688,
0.009720474481582642,
0.02857966162264347,
0.0445... |
<p>I have a second order Markov chain with 4 states {A,T,C,G} (the 4 DNA nucleotides).</p>
<p>the transition matrix looks like this:</p>
<pre><code> A T C G
AA[0.1, 0.6, 0.2, 0.1]
AT[0.3, 0.1, 0.5, 0.1]
AC[0.5, 0.3, 0, 0.2]
AG[..., ..., ..., ...]
TA[..., ..., ..., ...]
TT[..., ..., ..., ...]
TC[..., ...... | g48770 | [
-0.02064800262451172,
-0.01966134086251259,
0.01649715006351471,
-0.014897540211677551,
0.00914238952100277,
-0.04631247743964195,
0.02511492557823658,
0.014963818714022636,
-0.05131690576672554,
-0.02094266749918461,
-0.04408508166670799,
0.015120607800781727,
-0.0009101089090108871,
-0.0... |
<p>Suppose I have 10 repeated measurements of a quantitative variable $X$ of the individuals within two groups (let's call them A and B). For each group, I have the estimated means of variable $X$ at the 10 time points, that is, $$\hat{\mu}_1^A, \hat{\mu}_2^A, \ldots, \hat{\mu}_{10}^A$$ and $$\hat{\mu}_1^B, \hat{\mu}_2... | g23726 | [
-0.019962036982178688,
-0.05177683383226395,
-0.02067342959344387,
-0.044344499707221985,
0.011726473458111286,
-0.04209863394498825,
0.005527637433260679,
-0.03418385237455368,
-0.06319741904735565,
0.021608533337712288,
0.011145859025418758,
0.02604995295405388,
0.026919027790427208,
0.0... |
<p>I am planning a study on alteration in AUC of a drug due to a surgery of gastrointestinal tract. It's a pre-post study. A group of patients will undergo blood sampling for AUC (area under curve) both before and after surgery. How can I calculate sample size using R?</p> | g65232 | [
-0.010316985659301281,
0.014570931904017925,
0.002800264395773411,
-0.058099474757909775,
-0.03785012289881706,
-0.06954281032085419,
0.003044805023819208,
0.007138821296393871,
-0.02343071810901165,
0.0231709573417902,
0.043813854455947876,
0.047173455357551575,
0.01944287121295929,
-0.00... |
<p>I've got two algorithms, $A$ and $B$, I want to evaluate. Both algorithms differ by the distribution of points they produce. Let us suppose that $A$ generates points from $P_S$ distribution while B generates points according to $P_T$ distribution.</p>
<p>Further, I've got a dataset of 21,000 points generated by alg... | g43665 | [
-0.0038683940656483173,
0.014936033636331558,
-0.010319320484995842,
0.0027536207344383,
0.024094367399811745,
0.013747908174991608,
0.011157318949699402,
0.019818982109427452,
-0.060532405972480774,
0.027879465371370316,
-0.0006803352735005319,
0.033930703997612,
0.03340146318078041,
0.02... |
<p>I'm currently sifting through my copy of Analysis of Financial Time Series 2nd Edition by Ruey Tsay, and one of the sections involves fitting a MA model to certain data (data set is <a href="http://faculty.chicagobooth.edu/ruey.tsay/teaching/fts/m-ew.dat" rel="nofollow">here</a>). Here's the fit with exact maximum l... | g65233 | [
0.034811392426490784,
-0.05735819786787033,
0.03054695576429367,
-0.005844790954142809,
-0.01044645719230175,
0.013895963318645954,
0.046154145151376724,
0.015161220915615559,
-0.04383718594908714,
0.05140330642461777,
0.027162179350852966,
-0.02468300238251686,
0.06327056139707565,
0.0098... |
<p>I have a dataset made our of several stacked datasets (one for each state). I want to check whether a zero inflated negative binomial model with data from an individual state is different from the ZINB made from the whole data (national). Are there any suggestions on how to do a test like this?</p>
<p>One idea I ha... | g65234 | [
0.01567186415195465,
-0.0069270930252969265,
0.004318951163440943,
0.0004187823797110468,
-0.025536691769957542,
-0.016271505504846573,
0.0058207083493471146,
0.027187515050172806,
0.005610924679785967,
-0.024028608575463295,
0.0184760894626379,
0.006145366467535496,
0.03514551371335983,
-... |
<p>Can anyone please give me an example of non-measurable real set? </p> | g65235 | [
-0.04169521853327751,
0.0400136336684227,
0.013689735904335976,
-0.03734814003109932,
-0.028940480202436447,
-0.031929392367601395,
-0.01762532815337181,
0.0071969968266785145,
-0.01895185187458992,
-0.019972117617726326,
-0.02809046022593975,
-0.028315039351582527,
0.00671825185418129,
0.... |
<p>When using PROCESS by Hayes I get a insignificant interaction effect but 2/3 of the conditional effects are significant. Is there still something I can say about this in my results? So for instance, there is no overall interaction significance but there is on the low levels?</p>
<p><img src="http://i.stack.imgur.co... | g23730 | [
0.0008421259699389338,
0.04153340682387352,
-0.01864071749150753,
-0.02351594902575016,
0.014907770790159702,
-0.015077699907124043,
0.036579400300979614,
0.012220554053783417,
0.01148119755089283,
-0.0250672847032547,
-0.014852738007903099,
0.01265260111540556,
0.023811956867575645,
0.018... |
<p>I am new to ML, and I am reading a paper about ML comparison. It underlines the comparison between two algorithms based on the t-test but it does not describe the process further. </p>
<p>I know what a t-test is, but I don't understand how to implement it for ML algorithm comparison.</p> | g65236 | [
0.04541635513305664,
-0.02451569028198719,
0.012949198484420776,
-0.05820324644446373,
-0.028414728119969368,
-0.04024418815970421,
0.028856191784143448,
0.050470370799303055,
-0.10019463300704956,
0.00651802122592926,
-0.03515857458114624,
0.01540210098028183,
0.04304656386375427,
0.02155... |
<p>A Poisson distribution can measure events per unit time, and the parameter is $\lambda$.
The exponential distribution measures the time until next event, with the parameter $\frac{1}{\lambda}$.
One can convert one distribution into the other, depending on whether it is easier to model events or times.</p>
<p>Now, a... | g65237 | [
0.036321770399808884,
0.020597120746970177,
-0.004355945158749819,
-0.07018124312162399,
0.014506812207400799,
-0.011364947073161602,
-0.04863496124744415,
-0.016879389062523842,
-0.016050491482019424,
0.0033803931437432766,
0.01841045543551445,
-0.028255553916096687,
-0.023522518575191498,
... |
<p>I'm currently working on our thesis and I got stuck with the analysis part for I am not sure which statistical test I should use. My work had 5 groups. 1 positive and 1 negative control and 3 experimental groups. Is it right to use a 2-way ANOVA? And should the controls be included in the ANOVA? I'd like to compare ... | g65238 | [
0.01759902760386467,
-0.03781423345208168,
0.015715496614575386,
0.030167166143655777,
-0.013621540740132332,
0.014592358842492104,
0.028821397572755814,
0.009371737949550152,
-0.019247354939579964,
0.006229243706911802,
0.05626526102423668,
0.0018569744424894452,
-0.032034747302532196,
0.... |
<p>The model is the following:</p>
<ul>
<li>You receive a hidden integer h from 1 to N (uniform distribution)</li>
<li>You take an action a numbered between 1 to M.</li>
</ul>
<p>Describing the entire model is a MxN probability matrix with each entry saying "The probability of taking action a given hidden number h"</... | g65239 | [
0.009256759658455849,
0.01972728967666626,
-0.015281923115253448,
-0.0019886689260601997,
-0.026301458477973938,
-0.044654104858636856,
0.03581421822309494,
0.03688078373670578,
-0.046272002160549164,
0.01857009530067444,
-0.047868985682725906,
0.04345235228538513,
0.047274280339479446,
0.... |
<p>I have 2 x 2 x 2 mixed design with two between subject factors (sex, organizer) and one within subjects factor (task). The group sizes of the 'sex'-factor is unequal. When I perform a factorial repeated measures ANOVA, I get the following warning message: </p>
<p><code>Warning: Data is unbalanced (unequal N per gro... | g65240 | [
-0.03723623603582382,
0.012662041932344437,
-0.004907639231532812,
-0.0586450919508934,
0.07510743290185928,
0.014048123732209206,
0.02276298962533474,
-0.042192261666059494,
-0.027020163834095,
-0.015274801291525364,
-0.03272969275712967,
0.005089793354272842,
0.029795130714774132,
0.0671... |
<p>End goal will be practical application (model building) by using time series analysis to analyze/forecast macroeconomic/finance data. </p>
<p>Background: I have taken stats, introductory econometrics, intermediate macro, micro in the past couple years, but is has been 10 years since I took my only calculus course.<... | g257 | [
0.026687761768698692,
0.006414277944713831,
0.0024637363385409117,
0.03583968058228493,
0.012935669161379337,
0.006538202986121178,
0.05518456548452377,
-0.028337324038147926,
-0.030696339905261993,
-0.021100204437971115,
0.019724730402231216,
-0.0038505801931023598,
0.07006166875362396,
-... |
<p>I have defined unigram, bigram and trigram (language) models with my training data. Now I am checking their fitness towards a test data by using Katz backoff with a fixed discount of 0.5 (mo Good-turing). If I start with a trigram, when there is a zero count, the trigram falls back to bigrams and if the bigram also... | g65241 | [
0.02423785626888275,
0.02305283211171627,
0.014320019632577896,
-0.011678229086101055,
0.014886921271681786,
-0.011539626866579056,
0.04099181666970253,
0.02437427081167698,
-0.04014555737376213,
-0.017831163480877876,
-0.014684884808957577,
0.06721127778291702,
0.03025006875395775,
0.0659... |
<p>I'm working on a project that involves 14 variables and 345,000 observations for housing data (things like year built, square footage, price sold, county of residence, etc). I'm concerned with trying to find good graphical techniques and R libraries that contain nice plotting techniques. </p>
<p>I'm already seeing ... | g23738 | [
0.02546316757798195,
0.017982635647058487,
0.01830471120774746,
-0.08115795254707336,
-0.08753710985183716,
-0.08452039957046509,
0.04391594976186752,
-0.025117728859186172,
-0.02220558375120163,
0.005826457403600216,
0.07499125599861145,
0.021013641729950905,
0.03406872600317001,
0.004658... |
<p>I have a question about Prop. 9.1 on page 307 in "Probabilistic Graphical Models"
(<a href="http://books.google.de/books?id=7dzpHCHzNQ4C&printsec=frontcover&dq=koller%20probabilistic&hl=de&sa=X&ei=NiouU9T9N-en4ATN54CYCg&ved=0CDAQ6AEwAA#v=onepage&q=koller%20probabilistic&f=false" rel="... | g65242 | [
0.004395068157464266,
-0.00838852021843195,
0.0002912405179813504,
-0.006871693301945925,
-0.006794849876314402,
-0.021484805271029472,
0.008900351822376251,
0.036336202174425125,
-0.0159824900329113,
-0.044767528772354126,
0.025763167068362236,
0.03283979743719101,
0.02596202865242958,
0.... |
<p>Gaussian discriminant analysis models learn $P(x|y)$ and then apply Bayes rule to evaluate
$$P(y|x) = \frac{P(x|y)P_{prior}(y)}{\Sigma_{g \in Y} P(x|g) P_{prior}(g) }.$$ Hence, they are generative models. Why then is it called discriminant analysis? If it is because we finally derive a discriminant curve between th... | g35171 | [
0.007630233187228441,
-0.04761889576911926,
0.005727754440158606,
-0.014877108857035637,
0.03795985132455826,
-0.0031227937433868647,
0.03133595362305641,
0.02182474173605442,
-0.018654409795999527,
-0.03797149285674095,
-0.03886447846889496,
0.08195847272872925,
0.06664713472127914,
0.028... |
<p>The multiplication of multivariate Gaussian distributions defined over some parameter vector of a given dimension can be achieved by the following. Assuming that the Gaussian is parametrized by the precision matrix ($\Lambda$) and mean ($\mu$). We can compute the new precision as:</p>
<p>$$
\Lambda = \Lambda_1 + \L... | g65243 | [
0.01196342520415783,
-0.0629521831870079,
-0.015706177800893784,
-0.029275216162204742,
-0.048194415867328644,
-0.004064527340233326,
-0.02447652444243431,
-0.046110767871141434,
-0.044777512550354004,
0.0334441252052784,
-0.0013163116527721286,
0.0004883295623585582,
0.020923392847180367,
... |
<p>We have data from random polling within a group of people, sampled over a long period of time. As the pool is relatively small and anonymity is crucial there is a high likelihood that we have duplicate samples (though we can't tell for certain because we'd expect responses to vary over time).</p>
<p>Does this someh... | g65244 | [
-0.033728551119565964,
-0.004463468212634325,
0.0032099492382258177,
-0.01829545386135578,
-0.015053162351250648,
0.045882631093263626,
0.03523394092917442,
-0.02685411274433136,
0.002587217139080167,
0.0726790800690651,
-0.013228453695774078,
0.01731620728969574,
-0.026138463988900185,
0.... |
<p>There are occasions where I would like to fit log-linear models where the independence assumption between observations is violated. It is the normal case that I have multiple observations from each subject. Is there a mixed-effects extension to log-linear models like there are for linear and generalized linear model... | g65245 | [
0.003681063884869218,
-0.029994338750839233,
0.023186441510915756,
-0.005316504742950201,
-0.04597379267215729,
-0.0037632158491760492,
0.02126983366906643,
0.0015801002737134695,
-0.013069299049675465,
-0.03700936213135719,
0.0188461784273386,
-0.02395663782954216,
-0.004337675869464874,
... |
<p>I have a data which is 100x1 vector. How can I display its empirical pdf in Matlab? Also, if I want to compare the pdf of three vectors on the same graph, then how to do that?</p>
<p>Right now I am using <a href="http://www.mathworks.com/matlabcentral/fileexchange/8578-pdfplot" rel="nofollow">pdfplot.m</a> file to ... | g37524 | [
0.043522074818611145,
-0.015616134740412235,
0.010032353922724724,
-0.07531620562076569,
-0.0028486421797424555,
-0.03200574219226837,
-0.02729863114655018,
-0.00729511771351099,
-0.08253975212574005,
-0.019262641668319702,
0.05034532770514488,
0.03705989941954613,
0.04029200226068497,
-0.... |
<p>I'm currently working on the classification with massive amount of data. Similar to the <a href="http://www.kaggle.com/c/lshtc" rel="nofollow">kaggle</a> one. Data input consist of features and multiple labels that can be hierarchically aligned. </p>
<p>At first I flattened the data and tried to learn multi-label ... | g65246 | [
0.0307775866240263,
0.006282573100179434,
-0.009290244430303574,
-0.007449393626302481,
-0.015222483314573765,
-0.04269559681415558,
-0.0013533555902540684,
0.062403809279203415,
0.005700770765542984,
-0.022738922387361526,
0.026799576357007027,
-0.02411162480711937,
0.07595513015985489,
0... |
<p>Imagine 2 models: 1 for production, 1 for revenue, have cross-section and time dummies.
Is it permissable to use CS in one and time in the other? How do I justify this? F-test for fixed effects is indicating this and also dummies I want to omit in each case are not really significant. </p> | g65247 | [
0.025153860449790955,
0.031192775815725327,
0.002812562510371208,
0.006468839477747679,
0.027700373902916908,
0.005887910723686218,
0.07079344242811203,
-0.008099532686173916,
-0.03922783583402634,
0.010466227307915688,
0.027330931276082993,
-0.01221510861068964,
0.06390298902988434,
0.039... |
<p>Regarding regression analysis, I once heard that "Replicate at various predictor values will allow for lack-of-fit analysis". I do not understand how to get this kind of statement? </p> | g23746 | [
0.003238328965380788,
-0.026776930317282677,
-0.019826706498861313,
-0.015475254505872726,
0.03553121164441109,
0.015568934381008148,
0.04100395366549492,
0.01100787241011858,
-0.047367654740810394,
-0.06500239670276642,
-0.05953649803996086,
0.03164907544851303,
0.05657092109322548,
0.032... |
<p>I thought it had to do with varying numbers of factors but based on the literature I have read it seems to do more with fixing/freeing of parameters. Any info would be greatly appreciated!</p> | g65248 | [
0.03137689828872681,
0.010355686768889427,
-0.031263742595911026,
-0.006459788419306278,
0.04421648383140564,
-0.024448702111840248,
0.09501878917217255,
0.06173211336135864,
-0.032730959355831146,
-0.009240071289241314,
-0.02482268586754799,
0.024377968162298203,
0.03479565307497978,
0.03... |
<p>I'm trying to do a pairwise test to calculate p-values between various products that are being evaluated by several assessors. I'm trying to reproduce what SAS is doing in R, and I'm running into an issue in one particular situation: when the items being compared (in my case SAMPLE) are complete for one item in the... | g23750 | [
0.03164314851164818,
-0.05358104035258293,
-0.0010950480354949832,
-0.002801283961161971,
0.010675610974431038,
-0.030512923374772072,
-0.0009240451618097723,
-0.006785036064684391,
-0.006981942802667618,
-0.010359248146414757,
0.010480847209692001,
0.003148433053866029,
-0.01657592318952083... |
<p>I have two time series:</p>
<ol>
<li><p>numbers of subscriptions per hours for 10 days, for a website.</p></li>
<li><p>the time where TV ads, for a specific TV channel, have been displayed e.g. 10:25AM on Monday 12 of August, TV AD1 displayed on CNBC as an example.
The issue with that time series is there is only t... | g23752 | [
0.006466664373874664,
0.01222718320786953,
0.003960127010941505,
-0.08550308644771576,
0.0030562144238501787,
-0.005832040682435036,
0.03251713886857033,
-0.022033417597413063,
0.00689068203791976,
0.004241171758621931,
0.04230006784200668,
-0.001007121754810214,
0.04663141444325447,
0.059... |
<p>How bad is this for my model? </p>
<p>I've used ML (maximum likelihood) with promax rotation and Kaiser on a dataset ($n>300$) to extract underlying factors to build a model. Eigenvalue selection was reset from $.1$ to $.5$, so as to focus on cases (questions) that explain the most covariance according to underl... | g65249 | [
0.0024162759073078632,
-0.024153869599103928,
0.002524287672713399,
-0.0355425588786602,
0.003660340327769518,
0.017700694501399994,
0.08776088804006577,
0.00854082778096199,
0.03587109595537186,
0.03330540657043457,
0.00814779195934534,
-0.0003883262979798019,
0.034436482936143875,
0.0343... |
<p>I am sorry if this question is too basic or was somewhere else here on Cr-Validated, but i didn't find anything suitable.</p>
<p>I study patients with cancer who were made a byopsy taking to test presence of cancer cellcs 12 prostate core samples. When core samples are explored, they are divided into two groups whe... | g23753 | [
0.024084633216261864,
-0.005786956753581762,
0.0064142500050365925,
-0.07873328775167465,
0.03293900191783905,
-0.03290736675262451,
0.0703292265534401,
-0.008848235011100769,
-0.024931930005550385,
0.039682429283857346,
0.007990718819200993,
0.037570782005786896,
0.046574074774980545,
0.0... |
<p><strong>Update: First part answered. Directly jump to the second part for those wanting to answer!</strong></p>
<p><strong>First Part</strong></p>
<p>I am trying to have a better understanding of what is a likelihood function and what is AIC.</p>
<p>Here is my current understanding: If we toss a coin 11 times and... | g65250 | [
0.03260892257094383,
-0.03613059222698212,
-0.01995139755308628,
-0.02402159757912159,
0.035974908620119095,
-0.03156436234712601,
0.06623072177171707,
0.004767267964780331,
-0.043841712176799774,
-0.007743997033685446,
-0.07169697433710098,
0.02161581628024578,
0.08219262957572937,
-0.035... |
<p>I am using libSVM for classification on a 3-class dataset. Using the option "-b 1" - for getting probability estimates for prediction - gives me surprising results. </p>
<p>I am reproducing the issue with a much simpler dataset here.</p>
<p>The option "-b" can take only two values: "-b 1" denotes we need probabili... | g65251 | [
0.01626579836010933,
-0.004487577360123396,
-0.0019824642222374678,
0.0176834799349308,
0.03702697157859802,
0.018659302964806557,
0.020442133769392967,
0.07982043921947479,
-0.07391870021820068,
-0.04014545679092407,
-0.008728202432394028,
0.034156862646341324,
0.06725414842367172,
0.0620... |
<p>I have to compare two data sets for similarity. I'm designing a piece of software which will help improve a drummers accuracy. The software displays a rhythm which the drummer then attempts to play. </p>
<p>The first set of data is the reference set of the timings of beats which have been played. </p>
<p>The secon... | g65252 | [
0.06860039383172989,
-0.009071344509720802,
0.002169984392821789,
0.009904497303068638,
-0.022572237998247147,
-0.04389283061027527,
0.07304976135492325,
-0.04410509392619133,
-0.06680120527744293,
0.016553489491343498,
0.0041302405297756195,
-0.004665702115744352,
-0.0013758777640759945,
... |
<blockquote>
<p><strong>Possible Duplicate:</strong><br>
<a href="http://stats.stackexchange.com/questions/44888/deletion-residuals">Deletion residuals</a> </p>
</blockquote>
<p>The $i^{th}$ deletion residual $e_{−i}$ is defined as $e_{−i}=y_{i}−X^{⊤}B_{−i}$
where $X^{⊤}$ is the $i^{th}$ row of the design matri... | g49722 | [
0.037355076521635056,
-0.051745135337114334,
-0.00906381756067276,
0.01796998828649521,
-0.014831018634140491,
0.009252378717064857,
0.01001060102134943,
-0.004989671986550093,
-0.03286696970462799,
0.04523416981101036,
-0.018540097400546074,
0.006858609616756439,
0.026481565088033676,
0.0... |
<p>I have a three-node matrix with two edges (A-B and A-C). I would like to determine what the probability is starting from B and ending at C in exactly 100 steps.</p>
<p>I have only written out probabilities:</p>
<pre><code>P(A|B) = 1
P(B|A) = 0.5
P(A|C) = 1
P(C|A) = 0.5
</code></pre>
<p>But there are so many combi... | g35177 | [
0.037158071994781494,
0.028589416295289993,
0.01628231629729271,
-0.011921961791813374,
0.048418864607810974,
-0.046280842274427414,
0.01854686811566353,
0.03869742527604103,
-0.035540323704481125,
0.014607815071940422,
-0.02165140211582184,
-0.0005268483655527234,
0.04281666502356529,
-0.... |
<p>Let $X_1, ..., X_n$ be a random sample from $\mathrm{Exp}(\lambda_1)$ and $Y_1, ..., Y_m$ be a random sample from $\mathrm{Exp}(\lambda_2)$. I have found the generalized likelihood ratio test (GLRT) statistic $\Lambda$ for testing $H_0:\lambda_1 =\lambda_2$ vs $H_1:\lambda_1 \neq \lambda_2$ is $\Lambda=\frac{n^n m^m... | g23759 | [
0.009179250337183475,
-0.02330166846513748,
-0.02244156412780285,
-0.01234598271548748,
-0.019530922174453735,
-0.00178159074857831,
-0.00013490626588463783,
-0.01516089215874672,
-0.04569508880376816,
0.026331735774874687,
0.0222126804292202,
0.03815275803208351,
0.02661883644759655,
0.01... |
<p>i'm writing a few convenience functions for exploring datasets. For that, I have to guess the type of data from the values. What I'm looking for are some good rules of thumb.</p>
<p>Some easy cases:</p>
<ul>
<li><code>['spam', 'eggs']</code> is nominal, because the dataset contains strings.</li>
<li><code>[true, f... | g43720 | [
0.017056642100214958,
0.03297446668148041,
-0.0399068258702755,
-0.08545996248722076,
0.01444757916033268,
-0.07299724966287613,
-0.022388065233826637,
-0.00613070372492075,
-0.04170556738972664,
0.007304913830012083,
0.003298223251476884,
0.032387785613536835,
0.08166974782943726,
0.00691... |
<p>I have run 13 data-stream classification approaches on 8 different datasets, giving a 8x13 result table. I was hoping to use the Friedman test to test for a significant difference between the approaches. However one of the approaches can not be used on two of the datasets so there are two missing values in my result... | g23761 | [
0.043462276458740234,
-0.043624404817819595,
-0.01744886115193367,
-0.055539052933454514,
0.006651935167610645,
-0.009456012398004532,
0.01118558831512928,
-0.002044292166829109,
-0.046765461564064026,
-0.01741170696914196,
-0.039447709918022156,
0.001706268871203065,
0.01503352727741003,
... |
<p>I have a monthly average for a value and a standard deviation corresponding to that average. I am now computing the annual average as the sum of monthly averages, how can I represent the standard deviation for the summed average ?</p>
<p>For example considering output from a wind farm:</p>
<pre><code>Month ... | g65253 | [
-0.006416059099137783,
-0.007271953392773867,
-0.01668042317032814,
-0.04187996685504913,
-0.03900979459285736,
-0.014527728781104088,
0.04879789799451828,
0.025181658565998077,
-0.033083226531744,
-0.03317393362522125,
0.02650422975420952,
0.019152618944644928,
0.05412333831191063,
0.0312... |
<p>I have the following experiment. My predictors are: Plant area, 6 types of plants, 5 time points and 12 replicates for class. Time points are not equally spaced. A normal plot of Area vs. time will show $6\times 12\times 5$ points in the plot which doesn't reflect the fact that 5 of those points correspond to the sa... | g23762 | [
-0.0005583249730989337,
-0.010858063586056232,
-0.006726852152496576,
-0.07297593355178833,
-0.040473584085702896,
-0.04224744811654091,
0.07364712655544281,
-0.01422489807009697,
-0.014710177667438984,
-0.015543824061751366,
0.051288824528455734,
0.014649071730673313,
0.07881928980350494,
... |
<p>I do not think that the following problem can be solved with k-means clustering. I am not sure though. Okay, let me describe the problem. I need to find a way or an algorithm that groups members of a given data set (of positive integers) so that the difference between group means is <strong>minimized</strong> (not m... | g65254 | [
-0.03408345580101013,
0.0015816509258002043,
0.011600027792155743,
-0.034064505249261856,
0.012344944290816784,
-0.04723073169589043,
-0.05412324517965317,
-0.04180435091257095,
-0.03840957209467888,
-0.01381646003574133,
0.0061695389449596405,
0.044032879173755646,
0.0065267994068562984,
... |
<p>There's this large, well-mixed vat containing some unknown but finite varieties of marbles:
$$\{v_{1},v_{2},v_{3},...,v_{k}\}$$
Some varieties are more common than others.</p>
<p>Marbles are going to be pulled out of this vat by some machine. Each time you run the machine, it produces a set containing $q$ different... | g65255 | [
0.012384218163788319,
0.029532024636864662,
0.006957726087421179,
-0.028298981487751007,
0.005084075964987278,
-0.018899593502283096,
0.06166164204478264,
0.02064191736280918,
-0.020265182480216026,
0.0307613518089056,
-0.019558601081371307,
0.021977275609970093,
0.047508906573057175,
0.01... |
<p>I am experimenting with the eigenfaces algorithm, and I am unclear on a number of the finer points of the technique. For starters, consider the matrix of images used to do the initial PCA. Is it "better" to have only images of different individuals in that matrix? Or is it useful to include multiple images of the sa... | g65256 | [
-0.0016253823414444923,
-0.005837421398609877,
0.02776508964598179,
-0.05012841522693634,
-0.01876169443130493,
-0.060779839754104614,
0.11583220958709717,
0.035886529833078384,
-0.02215554565191269,
0.01892969012260437,
0.02337259240448475,
-0.01236917357891798,
0.03189580515027046,
0.061... |
<p>I am involved in a project that is attempting to measure the impacts of person-level, county-level and medical service area-level predictors on individual probability of returning to a hospital within a year window.
I see this as a 3 level random effect logistic regression model. There are lots of predictors, prob... | g49506 | [
-0.01465550996363163,
-0.0036510785575956106,
-0.00948861800134182,
-0.04520701989531517,
-0.03351859375834465,
-0.04110490903258324,
-0.027048259973526,
0.02807016856968403,
-0.008996713906526566,
-0.028550904244184494,
0.055159371346235275,
0.026900095865130424,
0.005999593064188957,
0.0... |
<p>I am running an experiment where I collect two data sets and I wish to measure the difference between the two. The two data sets are independent, with unknown probability distribution, and may not always have the same length.</p>
<p>Calculating the mean difference is easy as pie, but i also want a measure of the st... | g43728 | [
0.0013757793931290507,
0.00792845617979765,
0.008779172785580158,
-0.04686587676405907,
-0.03737131506204605,
0.001754800439812243,
-0.02124328352510929,
0.016420699656009674,
-0.0678308755159378,
-0.001345084048807621,
0.003040843177586794,
0.021766403689980507,
0.000760901952162385,
-0.0... |
<p>I'm hoping one of the more experienced R programmers/statisticians out there can help me with something, or explain why what I'm trying to do is stupid :-)</p>
<p>In the past, I've done analysis of survey data in SPSS. I'll often create contingency tables that uses a computed segmentation variable to see if member... | g65257 | [
0.026661569252610207,
-0.05653247982263565,
-0.005062432494014502,
-0.04094374552369118,
-0.023271454498171806,
-0.07224185019731522,
0.023152224719524384,
0.04032216966152191,
0.0016706547467038035,
-0.012049274519085884,
0.01411423645913601,
0.0022130818106234074,
0.049352191388607025,
0... |
<p>There's a heuristic, which I find appealing, that says that for every stochastic algorithm, there should be at least one deterministic algorithm that performs better, provided the universe isn't adversarial. I first heard this principle articulated by Eliezer Yudkowsky <a href="http://lesswrong.com/lw/vp/worse_than_... | g65258 | [
0.06733451783657074,
-0.0004164653364568949,
0.022831540554761887,
-0.034887976944446564,
-0.026640400290489197,
-0.02891254797577858,
-0.000919697224162519,
0.028792042285203934,
-0.01541894394904375,
0.03131384029984474,
0.0012705072294920683,
0.018655626103281975,
0.051180150359869,
0.0... |
<p>I want to compare several learning algorithms in a single domain. In the book " Evaluating Learning Algorithms" I saw the procedures to compare two learning algorithms in a single domain or multiple algorithms in multiple domains. I assume that the procedure to evaluate multiple learning algorithms in a single domai... | g28471 | [
0.02849104069173336,
-0.06214144453406334,
0.0024396481458097696,
-0.03454118221998215,
0.028572319075465202,
0.0031253097113221884,
0.0979684442281723,
0.01372173335403204,
-0.023134106770157814,
0.0229654461145401,
0.01808861829340458,
0.011216365732252598,
0.041249554604291916,
0.060239... |
<p>I am working with two data sets of unequal sample sizes of 998 and 857.
Average of first (998 samples), come out to be higher than the other dataset.
To my surprise, when I split my complete data into unequal halves; first into 803 and 195 samples and other also into 819 and 38 samples.
then comparison of average v... | g65259 | [
0.03219884634017944,
-0.0030538432765752077,
0.01638641580939293,
-0.043482474982738495,
0.02262137643992901,
0.0052009932696819305,
-0.03795064985752106,
0.0647973120212555,
-0.054404065012931824,
-0.025642696768045425,
0.007384925615042448,
0.03761624917387962,
0.027181698009371758,
-0.0... |
<p>I was provided with quite a small sample of labeled (variable of interest) observations to train a model to predict unlabeled observations. All the observations are associated with many covariates. I'm assuming that the trained model will do better in measure of how well does this small labeled sample represent the ... | g39199 | [
-0.029317287728190422,
-0.07747144252061844,
0.013108565472066402,
-0.07472319155931473,
0.014532756060361862,
-0.005889272317290306,
-0.006773226894438267,
0.03479605168104172,
-0.004517676308751106,
-0.011403873562812805,
0.04982636496424675,
0.02039427123963833,
0.04792889952659607,
0.0... |
<p>I found a paper about using naive bayes classification for identifying interested user. In that paper, they use some characteristic to define whether user is interested or not. However, they do not explain the step by step method to build the classifier.</p>
<p>This is the link where i found the paper : <a href="ht... | g23771 | [
0.012792263180017471,
-0.02385496161878109,
0.012333933264017105,
0.008861674927175045,
-0.0031857765279710293,
-0.0009662873344495893,
0.01921169087290764,
0.017636625096201897,
-0.007199345622211695,
-0.06380122154951096,
-0.003341065952554345,
0.06389360129833221,
0.06274121254682541,
0... |
<p>I'm trying to do a follow up test for a mixed model ANOVA, and I figured that I need do a Mixed Model t test also known as Toothaker's test. I just don't know how do it. I was wondering if anyone has an Excel sheet that can calculate this for me, because I know SPSS can't.</p>
<p>I'm doing a mixed model ANOVA and I... | g65260 | [
0.018624834716320038,
-0.03154279664158821,
0.008503694087266922,
-0.04235463589429855,
-0.020005494356155396,
0.0032243537716567516,
0.04903031513094902,
0.01226456556469202,
-0.01167172659188509,
-0.000047564837586833164,
-0.008069297298789024,
-0.0068673971109092236,
0.025923456996679306,... |
<p>I am trying to understand what these results mean for my analysis. The p-value seems extremely high, although the actual correlations do seem to reflect my data.</p>
<pre><code>Pearson's product-moment correlation
data: domain.of.choice_stats and objects.of.choice_stats
t = -0.4177, df = 10, p-value = 0.685
a... | g65261 | [
-0.011468550190329552,
0.006189987063407898,
-0.03405654802918434,
-0.020688919350504875,
0.04842006787657738,
0.028432471677660942,
0.037697870284318924,
-0.02405289001762867,
0.020789125934243202,
-0.01680007018148899,
-0.02522829733788967,
-0.008540934883058071,
0.018198790028691292,
-0... |
<p>I have a basic information theory question. I am fitting a highly parameterized model to some data. In general:</p>
<p>$$
y = \sum\limits_{i=1}^{13} \alpha_i X_i
$$</p>
<p>Currently I use gradient descent to find $\alpha$. The general assumption would be that the $X_i$s are i.i.d. However I am not sure if this nec... | g65262 | [
0.01376075204461813,
0.01726500317454338,
-0.0149484071880579,
-0.035581301897764206,
0.0328114815056324,
-0.0073930141516029835,
0.04026981070637703,
0.03372587636113167,
-0.03669845685362816,
0.004528135061264038,
-0.029545089229941368,
-0.026701634749770164,
0.009373274631798267,
0.0748... |
<p>I'm currently looking for a test having for null hypothesis that the sample does <strong>not</strong> come from observing a normally distributed random variable. In other words, I'd like to know if there's a test that's opposite to the K-S, Anderson-Darling, Shapiro-Wilk or Jarque-Bera.</p> | g65263 | [
0.02560325711965561,
-0.02807905711233616,
-0.0010833442211151123,
-0.05676134675741196,
-0.03878174349665642,
-0.010800241492688656,
-0.00451741274446249,
0.037225328385829926,
0.0596357025206089,
-0.05600335821509361,
0.033798206597566605,
0.03352748975157738,
0.02855001389980316,
0.0336... |
<p>Im new to regression, but quit experienced in classification and machine learning. In Classification, the state of the art technique for classification is SVM, so the first solution I would like to use for my regression problem is an SVM one. </p>
<p>The regression problem im trying to solve can be described as fol... | g65264 | [
0.011753262020647526,
0.013433244079351425,
0.003955019637942314,
0.01060200110077858,
-0.006393211893737316,
-0.06609393656253815,
0.03248835727572441,
0.06840250641107559,
-0.08369103819131851,
0.02620641514658928,
-0.0061567481607198715,
0.033870112150907516,
-0.015200125053524971,
0.04... |
<p>I just wanted to know how to do <strong><em>Heteroscedasticity Test on a Univariate Model</em></strong>?</p>
<ul>
<li>ex: an univariate autoregressive model</li>
<li>ex: an univariate ARCH/GARCH model</li>
</ul>
<p>If it is possible, how does one do that in <code>R</code>? </p> | g65265 | [
0.008430157788097858,
-0.024534190073609352,
-0.02551722340285778,
-0.02767535299062729,
0.03299352899193764,
0.025447187945246696,
0.0005387510755099356,
0.029012801125645638,
0.010016749612987041,
0.0004783668555319309,
0.012005338445305824,
0.07004184275865555,
0.05433198809623718,
0.01... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.