question stringlengths 37 38.8k | group_id stringlengths 2 6 | sentence_embeddings listlengths 768 768 |
|---|---|---|
<p>I need a bit of guidance here on a logit regression outcome. From the model I got logit results below <img src="http://i.stack.imgur.com/CtTN3.jpg" alt="enter image description here">
So I thought everything looks good: P value < 0.05 seems to be statistically significant. But once I plot predict vs actual and tr... | g66388 | [
-0.010442272759974003,
-0.0026739095337688923,
-0.010868017561733723,
-0.03103005886077881,
0.008234518580138683,
-0.018640797585248947,
0.03941817581653595,
0.04424503073096275,
-0.043277494609355927,
-0.022172030061483383,
-0.015521794557571411,
0.00878544058650732,
0.09511254727840424,
... |
<p>Homogeneity of clusters can easily measure by calculating the sum of squared error (SEE): $$SSE = \sum_k \sum_{i \in c_k} \| x_i - \overline{c_k} \|^2$$ where $\overline{c_k}$ is the mean vector of cluster $k$.
A disadvantage of this measure might be that it favors compact clusters.
Another idea to emasure cluster h... | g66389 | [
-0.054425422102212906,
-0.01105524506419897,
-0.0064241704531013966,
-0.034631699323654175,
0.001246824162080884,
-0.03451220691204071,
-0.014702629297971725,
-0.0006149086984805763,
-0.052177440375089645,
0.014172143302857876,
0.02610965259373188,
0.011823859997093678,
0.025652091950178146,... |
<p>I have a population of 6 million text files with which I want to perform sentiment analysis (and text analysis more generally). I will need to manually hand code a subset of these texts into positive and negative. Is there an equivalent of a "power calculation" or rules of thumb to help me determine how large my sam... | g66390 | [
-0.00162131164688617,
-0.0064017134718596935,
-0.015993233770132065,
-0.03431537002325058,
-0.035153184086084366,
-0.05793371424078941,
-0.030644478276371956,
0.06289277225732803,
-0.04623878374695778,
0.04793080687522888,
0.031651828438043594,
0.00018059634021483362,
0.03514374420046806,
... |
<p>I don't know whether this post deserves to be here or in Stack Overflow. I am looking for the good book [one that is usually recommended as the text book] for teaching the introductory statistics and econometrics in <code>R</code> to the undergraduates. </p>
<p>Thanks.</p> | g66391 | [
0.04797367751598358,
-0.014696437865495682,
0.002064105123281479,
-0.05233108252286911,
0.02130615897476673,
0.0492825023829937,
0.014618787914514542,
-0.0015177999157458544,
-0.03097137250006199,
0.036487605422735214,
0.04105761647224426,
-0.006213195621967316,
0.032525915652513504,
-0.02... |
<p>I am currently analyzing the relationship between Google Search frequency and the CDS market. I used a monthly backward rolling regression to determine the 30 search queries which have the biggest impact on the CDX index measured in the t-statistic for each month. In the next step I want to construct a sentiment in... | g23334 | [
-0.026616886258125305,
0.09761251509189606,
-0.020100459456443787,
0.009593397378921509,
-0.0373794324696064,
-0.017788881435990334,
0.0185054000467062,
0.0032386058010160923,
-0.001869727042503655,
-0.029517585411667824,
0.01047475915402174,
0.03591129183769226,
0.07175717502832413,
0.035... |
<p>In CHAID, the categories are merged when P>alpha in the first step.</p>
<p>BUT</p>
<p>Since CHAID uses Chi-square statisitic, if p-value < alpha, we reject the null ( Independence), hence, meaning the categories are not independent, thus Merge.But this line of thought is not the case reading the algorithm steps... | g66392 | [
0.018325991928577423,
0.047194380313158035,
0.022427095100283623,
-0.016242023557424545,
0.010319775901734829,
0.027895495295524597,
0.0006574811413884163,
0.08599919825792313,
-0.02806258760392666,
0.0047476626932621,
-0.023306861519813538,
-0.018675489351153374,
0.06575919687747955,
0.04... |
<p>I have a logistic regression model with several variables. I want to test the hypothesis of, say $a \beta_i = b \beta_j$ for constants $a,b$. I know that this can be theoretically done with an $F$-test; but how do I technically do it in R?</p>
<p>What about in the case where I have a factor variables, to the differ... | g66393 | [
0.016755802556872368,
-0.0321381501853466,
-0.007369881961494684,
-0.004312911536544561,
0.042421840131282806,
-0.07453074306249619,
-0.0010992835741490126,
-0.032414283603429794,
-0.061600230634212494,
-0.004381093662232161,
-0.041126005351543427,
0.05663421005010605,
-0.023624561727046967,... |
<p>In a highly imbalanced binary classification (rare class < 10% of whole data), when I perform random sample selection (less than 15% of whole data to be selected for training) in a trial of 1000 times, there are some iterations whereby the selected samples only belong to the majority class, meaning that the train... | g17126 | [
-0.039869677275419235,
0.016383957117795944,
0.008577282540500164,
-0.030697382986545563,
0.03943018615245819,
-0.0027019442059099674,
0.0413777232170105,
0.07149281352758408,
0.03279358521103859,
0.02020827867090702,
-0.0018431127537041903,
0.06416585296392441,
-0.0010528890416026115,
0.0... |
<p>I have a dataset with 1 continuous variable(y), 2 categorical variables(x1, x2) and one variable that has the unique values (0,1,5,9,13) that stand for miles (x3). I want to run a regression of y on x1, x2 and x3. I am really concerned about how to treat x3. I am guessing I can't treat it as a categorical variable... | g66394 | [
-0.0007640760741196573,
-0.01279823575168848,
-0.045655954629182816,
-0.04104827344417572,
0.01209921296685934,
-0.04572933539748192,
-0.006616281345486641,
0.04409865662455559,
-0.05094567686319351,
-0.010887736454606056,
0.013150878250598907,
0.0383702889084816,
0.027284327894449234,
-0.... |
<p>We have a linear model
\begin{align}
Y=X\beta + \varepsilon
\end{align}
where $X$ is $n \times p$ ($n > p$) matrix of full rank. All assumptions of linear model hold.</p>
<p>I have to prove inequality which is connected with the elements $h_{ij}$ of the hat matrix $H=X(X'X)^{-1}X'$. The inequality is:
\begin{al... | g66395 | [
-0.04909415915608406,
-0.02407410927116871,
-0.007899782620370388,
0.019214827567338943,
0.02181868441402912,
-0.0343807227909565,
0.01740589365363121,
-0.005251317750662565,
-0.05009400099515915,
0.028131965547800064,
-0.05513491854071617,
0.06645689904689789,
-0.05899443477392197,
0.0223... |
<p>Say we have a Markov chain with a countably infinite state space, e.g. the non-negative integers.</p>
<p>If we can form and solve equations for the stationary distribution {$\pi_i$}, that satisfies:</p>
<p>$\pi_i = \sum_{j} P_{ji}\pi_j , \ \ \ \ \ i \in \{0,1,2,...\}$</p>
<p>$\sum_{j} \pi_j = 1$</p>
<p>Is it gua... | g39502 | [
0.0047352188266813755,
0.002690361812710762,
0.0014788118423894048,
0.02897467091679573,
0.024704769253730774,
-0.08208728581666946,
-0.03785184025764465,
0.0051293629221618176,
0.03624165803194046,
-0.03945441544055939,
-0.05478967726230621,
0.0278460830450058,
-0.05559983476996422,
-0.02... |
<p>Let's say I have a (n x m) centered data matrix $A$ with SVD $A = U \Sigma V^{T}$.</p>
<p>For example, m=50 columns (measurements) that are spectra with n=100 different frequencies. The matrix is centered so the rows of the matrix have their mean subtracted. This is for interpreting the left singular vectors as pri... | g66396 | [
0.059398990124464035,
-0.05032213032245636,
0.004959992598742247,
-0.035130541771650314,
0.004846879281103611,
-0.037636395543813705,
0.08267346024513245,
0.05024144798517227,
-0.011204872280359268,
0.007504325360059738,
-0.004641271196305752,
0.037878166884183884,
0.0747399851679802,
0.03... |
<p>I have conducted a confirmatory factor analysis (CFA) to test the fit of a model with 5 factors and 5 items per factor. I used the modification indices to alter the model until I obtained statistics indicating an acceptable fit of the model to my data. </p>
<p>As others have done in my area I then conducted a princ... | g66397 | [
0.03919120505452156,
-0.05804624408483505,
0.015486489050090313,
-0.06432918459177017,
0.01332143135368824,
-0.007527161855250597,
0.05927734822034836,
-0.011161817237734795,
0.0008260209579020739,
-0.015182959847152233,
0.03520980104804039,
-0.007371516898274422,
-0.016494976356625557,
-0... |
<p>In R I would like to solve a system of linear equations with constraints to preserve monotonicity. I can do this easily with no constraints on the coefficients. Here is an example:</p>
<pre><code> [,1] [,2] [,3] [,4] [,5] [,6] [,7]
[1,] 0.6945405 0.1157702 0.004973632 0.0000... | g25376 | [
0.007728205528110266,
-0.008204863406717777,
0.026677729561924934,
0.017030568793416023,
0.0776732936501503,
-0.04541316255927086,
0.007236824370920658,
-0.06170574575662613,
-0.047963716089725494,
0.00042879980173893273,
-0.08934947848320007,
0.0234160665422678,
-0.007583299186080694,
0.0... |
<p>I have a problem with a goodness-of-fit question.. I have this question I need to answer but I have no idea how:</p>
<p>Why do we need to test the goodness-of-fit of a distribution of a random phenomenon to a parametric distribution (one where the distribution is known)?</p>
<p>I had the observations of a random v... | g29371 | [
0.06507460027933121,
0.005002561956644058,
0.010647338815033436,
-0.054205022752285004,
0.007284903433173895,
0.009069561958312988,
0.016127565875649452,
0.010183518752455711,
-0.0059256525710225105,
-0.03551512584090233,
0.005816377233713865,
0.008911196142435074,
0.027129702270030975,
-0... |
<p>The formula for calculating sample size in a two sided hypothesis on two proportions is:</p>
<p>$$n_1\ge \frac{\left(Z_{1-\frac{\alpha}{2}}\cdot\frac{S_0}{S_1}+Z_{1-\beta}\right)^2S_1^2}{(p_1-p_2)^2}$$</p>
<p>I'm asked to explain why in one sided hypothesis instead of $Z_{1-\alpha/2}$ we have $Z_{1-\alpha}$, with ... | g66398 | [
0.021853622049093246,
-0.007445392198860645,
-0.02208031713962555,
-0.05360283702611923,
0.021141652017831802,
-0.02016124315559864,
0.04275370389223099,
0.026280364021658897,
-0.02926318533718586,
-0.010009920224547386,
0.02099362574517727,
0.02976033464074135,
0.01884443499147892,
0.0955... |
<p>I would like to compute tail probabilities of the standardized multivariate normal distribution for different dimensions. For example, in the case of bivariate normal I need to compute the gray area on the figure pasted below (In this particular case, the area is defined by $\mathbf{x} > 2$.)</p>
<p><img src="ht... | g66399 | [
0.019315460696816444,
-0.024804307147860527,
-0.0050373561680316925,
-0.04647590592503548,
-0.047351665794849396,
-0.02896990068256855,
0.04962294176220894,
0.035227421671152115,
-0.042166244238615036,
-0.0120514165610075,
0.017300238832831383,
0.010876715183258057,
0.06003916263580322,
-0... |
<p>I have $N$ samples $x_i \sim p(x|y)$ for $y = y_0$.
I don't know apriori what $y_0$ is but I know its a fixed value.
I do not have the analytic form of $p(x|y)$, $p(y|x)$, $p(x,y)$.
Instead I have discrete probability lookup tables(that I can interpolate).</p>
<p>How can I now infer $y_0$?</p>
<p>I originally tho... | g66400 | [
-0.00397465331479907,
-0.00899533461779356,
0.005873445421457291,
-0.027977457270026207,
-0.031346600502729416,
-0.03699250519275665,
-0.009813885204494,
-0.02419097349047661,
-0.017367975786328316,
-0.05515348166227341,
-0.028898248448967934,
0.012442933395504951,
0.02353348210453987,
-0.... |
<p>I am using Support Vector Machines from "e1071" package in R.
For standard IRIS data the code is:</p>
<p>data(iris);
attach(iris);
x <- subset(iris, select = -Species);
y <- Species;
model <- svm(x, y)</p>
<p>After that using function "predict" I can get prediction with the trained model for any data from... | g25378 | [
0.008598643355071545,
0.035917893052101135,
0.00664904247969389,
-0.006425994914025068,
-0.026414278894662857,
-0.04778502508997917,
0.007267643231898546,
0.0753677561879158,
-0.046546339988708496,
-0.011956503614783287,
0.0243524182587862,
0.017237070947885513,
0.03186364471912384,
0.0111... |
<p>Suppose that $X$, $Y$, and $W$ are random variables. Also consider the random variable $Z=XY$. I am interested in comparing the Pearson correlation coefficients $\rho(Z,W)$ to the correlation coefficients $\rho(X,W)$ and $\rho(Y,W)$. I have a data set where the correlation coefficients seem to roughly obey</p>
<p>$... | g66401 | [
0.015585637651383877,
-0.01658347062766552,
0.02443845570087433,
-0.01929786615073681,
-0.0027660245541483164,
-0.009060956537723541,
0.020301848649978638,
-0.05289587005972862,
0.011340871453285217,
0.0033944332972168922,
-0.02892211265861988,
0.07872270047664642,
-0.06050920858979225,
0.... |
<p>The PDF of the generalized Beta distribution in the interval $[A,B]$ is defined as:</p>
<p>$$f(x) = \frac{(x-A)^{\alpha-1}(B-x)^{\beta-1}}{(B-A)^{\alpha+\beta-1}\mathrm{B}(\alpha,\beta)}$$</p>
<p>for $A<x<B$, and $f(x)=0$ otherwise. Here we assume that $\alpha,\beta>1$ and $A<B$.</p>
<p>Consider a PDF... | g66402 | [
0.008794854395091534,
-0.025610869750380516,
-0.015489780344069004,
-0.002453938592225313,
0.03768282011151314,
-0.001714591053314507,
-0.020124105736613274,
0.013383756391704082,
-0.05629889667034149,
0.027848953381180763,
0.036970242857933044,
0.016107425093650818,
0.02060687728226185,
-... |
<p>I have performed a survey in which users click on an image and the position of this click is recorded. I want to see if where a user clicks is independent of an attribute of the user (say gender). </p>
<p>To perform this gender analysis, I have split the image into blocks and calculated the number of clicks in each... | g25381 | [
-0.008845016360282898,
0.050414860248565674,
0.0073944018222391605,
-0.02085227333009243,
0.02004900760948658,
-0.07740481942892075,
0.033834949135780334,
0.03578097000718117,
-0.04148780554533005,
0.01068939920514822,
-0.0110779395326972,
0.03353988751769066,
0.012102470733225346,
-0.0083... |
<p>I am looking for a statistical method to define the variance/ diversity / inequality in a set of observations. </p>
<p>For example:
If I have following (n=4) observations using 4 data points, here the diversity/variance/inequality is zero. </p>
<pre><code>A-B-C-D
A-B-C-D
A-B-C-D
A-B-C-D
</code></pre>
<p>In the ... | g37778 | [
0.013147266581654549,
0.028127368539571762,
-0.014687656424939632,
-0.04093684256076813,
0.049672771245241165,
-0.028988786041736603,
0.020149799063801765,
-0.003799521829932928,
-0.04371294379234314,
-0.04613656923174858,
0.020822761580348015,
0.0066168284974992275,
0.014353340491652489,
... |
<p>As question, I have found something similar <a href="http://www.graphpad.com/quickcalcs/ConfInterval1.cfm" rel="nofollow">here</a>, but how to do it in R?</p>
<p>Thanks.</p> | g25385 | [
0.04082256928086281,
-0.012980745173990726,
0.0015396543312817812,
-0.028846876695752144,
0.010497072711586952,
-0.10034215450286865,
0.02468697912991047,
-0.021140802651643753,
-0.07081520557403564,
-0.02774730883538723,
-0.012631396763026714,
0.024216458201408386,
0.08743690699338913,
0.... |
<p>If I am doing a two tailed $t$ test, i.e my null and alternate hypothesis are</p>
<p>$$H_0: \mu = 0$$
$$H_1: \mu \neq 0,$$</p>
<p>then would I choose and $\alpha$ value of $0.05$ for a $95$% confidence interval or a value of $0.025$?</p>
<p>EDIT: Also, will be degrees of freedom be $n - 2$ or $n - 1$?</p> | g45724 | [
0.03234696015715599,
0.006583366077393293,
-0.008718002587556839,
0.053579047322273254,
0.030174439772963524,
-0.0151900053024292,
0.01764237880706787,
-0.007803039625287056,
-0.01837320625782013,
-0.041361819952726364,
-0.0034346235916018486,
0.022843552753329277,
-0.021753503009676933,
-... |
<p>I'm dealing with hierarchical model where $Y_i$ are from normal distribution.
About variance the formulation is the following:
Similarly, the data contain substantial information about the measurement error, $\sigma^2$, so the relatively noninformative Jeffreys' prior, $l/\sigma^2$, was used for this parameter
So, w... | g66403 | [
0.049616388976573944,
-0.009254112839698792,
-0.010150040499866009,
-0.026178471744060516,
-0.025215057656168938,
0.02064158208668232,
0.06891464442014694,
-0.008214034140110016,
-0.04512893036007881,
0.009133095853030682,
-0.009325976483523846,
0.028382521122694016,
-0.037955816835165024,
... |
<p>If i test two hypotheses, one of which has a null that is -in fact- false and the other has a null that is -in fact- true, I want to know the probability that the first test will obtain a p value less than that of the second, given other parameters such as delta, sigma, and sample size. I am not interested in whethe... | g66404 | [
0.08535896986722946,
-0.02149103581905365,
-0.005285695660859346,
-0.0215249415487051,
0.016868559643626213,
-0.02307380549609661,
-0.006647688802331686,
0.040121760219335556,
-0.024553207680583,
-0.01353449746966362,
-0.023028407245874405,
0.013127485290169716,
0.0012425528839230537,
0.01... |
<p>I'm doing machine learning with a training set, validation set and test set.</p>
<p>I train with the L_BFGS algorithm. The training converges all the time. I have the default accuracy from scipy, which is quite high.</p>
<p>Then I have a regularization parameter that I optimize on the validation set. I do this wit... | g66405 | [
0.057252898812294006,
0.007019032258540392,
-0.014858188107609749,
-0.007960948161780834,
0.06999790668487549,
0.014440827071666718,
-0.019920488819479942,
0.03614785149693489,
-0.06778936833143234,
-0.06429195404052734,
-0.03989306092262268,
0.08247296512126923,
-0.021829208359122276,
0.0... |
<p>I have some previous knowledge about classification, however am now struggling in understanding how classification algorithms can deal with features with different dimensions. Up to now I have only used a feature vector consisting of scalars, where each scalar had one feature for itself (e.g. the variance of the dat... | g45729 | [
0.029999325051903725,
-0.029669126495718956,
0.011916439980268478,
-0.03487171605229378,
-0.037922441959381104,
-0.03909112140536308,
0.025687184184789658,
0.02832302264869213,
-0.08511447161436081,
-0.01550090592354536,
0.02092858776450157,
0.06068059056997299,
0.032792963087558746,
0.049... |
<p>Consider a variable that can take both negative and positive values, and that has the following density plot:</p>
<p><img src="http://i.stack.imgur.com/e25MP.jpg" alt="enter image description here"></p>
<p>I am trying to identify the distribution of this variable. The density plot resembles that of a Gamma distrib... | g764 | [
0.044184066355228424,
-0.04483775794506073,
-0.013179706409573555,
-0.06722442060709,
-0.03758182004094124,
0.006152353249490261,
-0.007716687396168709,
-0.07704653590917587,
-0.02937973104417324,
-0.013456756249070168,
0.06341822445392609,
0.007824872620403767,
0.03379763290286064,
0.0069... |
<p>I am performing MCMC with pyMC on a nonlinear model, specified in <a href="http://stats.stackexchange.com/q/89143/41492">Probabilistic modelling MCMC question with pyMC</a>
Imagine I have 2000 points of experimental data, normally distributed:</p>
<pre><code>data = np.random.normal(.2, 1, 2000)
</code></pre>
<p>I... | g66406 | [
0.03019827790558338,
-0.0408436544239521,
-0.004707739222794771,
-0.05738558992743492,
0.04400693252682686,
0.006347518879920244,
0.0044211638160049915,
0.01738118566572666,
-0.04014096036553383,
-0.06269636750221252,
0.017546597868204117,
0.0025790457148104906,
0.020317554473876953,
0.051... |
<h3>Context:</h3>
<p>I have two data sets from the same questionnaire run over two years. Each question is measured using a 5-Likert scale.</p>
<h3>Q1: Coding scheme</h3>
<p>At the moment, I have coded my responses on a [0, 1] interval, with 0 meaning "most negative response", 1 meaning "most positive response", and... | g66407 | [
-0.01842542365193367,
-0.03387970104813576,
-0.0157264806330204,
-0.0575106181204319,
0.019581589847803116,
0.010299960151314735,
0.034248437732458115,
0.013568112626671791,
-0.009253514930605888,
-0.003356822533532977,
0.06835350394248962,
0.02618333324790001,
0.06339719891548157,
0.01522... |
<p>Over the years, I picked up many Statistics Concepts in by a variety of situations and means. I studied some Statistics maybe for a couple semesters almost 10 years back. But I also picked up concepts while doing Machine Learning work. I only understood things in a narrow scope - I always tried to get away knowing o... | g25395 | [
0.0130334896966815,
0.06361715495586395,
0.0036021883133798838,
-0.006547597236931324,
-0.02975565753877163,
-0.06237030029296875,
0.06454675644636154,
-0.005688525270670652,
0.0023349574767053127,
-0.02004021219909191,
0.0051841409876942635,
-0.015143857337534428,
0.015701724216341972,
0.... |
<p>This is a question of definition, does the stats community differentiate these terms?</p> | g25396 | [
0.09752215445041656,
0.017021771520376205,
-0.021749334409832954,
-0.003076711669564247,
0.024251436814665794,
-0.004595338832587004,
0.024300627410411835,
-0.044162996113300323,
-0.014981879852712154,
-0.04454744607210159,
-0.03231615945696831,
-0.002887163544073701,
-0.016018863767385483,
... |
<p>If I try and fit the linear regression </p>
<pre><code>lm(y~V1+V3,data=x)
</code></pre>
<p>with data:</p>
<pre><code>structure(list(V1 = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L,
3L, 3L, 3L, 3L, 3L, 3L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4... | g25397 | [
0.025450406596064568,
-0.04184112697839737,
-0.00008421135862590745,
-0.0523926205933094,
0.0628872960805893,
-0.014588253572583199,
0.04833585396409035,
-0.03115144930779934,
-0.038856375962495804,
-0.04671420156955719,
-0.031145505607128143,
0.050537582486867905,
0.004418522119522095,
-0... |
<p>My features' every dimension has different range of value. I want to know if it is essential to normalize this dataset. Thanks</p> | g765 | [
-0.008595205843448639,
0.015066555701196194,
-0.01942906714975834,
0.009558642283082008,
0.0009186873794533312,
0.016669506207108498,
-0.0009737059590406716,
0.026103267446160316,
-0.07930143922567368,
-0.02399827353656292,
-0.037383101880550385,
0.06407644599676132,
0.02402750588953495,
0... |
<p>I am computing a very simple Kalman filter (random walk + noise model).</p>
<p>I find that the output of the filter is very similar to a moving average.</p>
<p>Is there an equivalence between the two?</p>
<p>If not, what is the difference?</p> | g45739 | [
0.012981737032532692,
-0.04595183581113815,
0.015030374750494957,
0.029481327161192894,
-0.006009843200445175,
-0.011461523361504078,
0.03143507242202759,
-0.0059425137005746365,
-0.05149564519524574,
-0.0029321787878870964,
-0.023142516613006592,
-0.0017779269255697727,
0.05149441584944725,... |
<p>I've got a data set which has volume of mail sent from 2001-2012, recorded by age group. That is, for seven different age groups, I have each age group's annual volume of mail sent over that time period.</p>
<p>I've run seven regressions in R--one for each age group--which simply regress volume of mail sent on time... | g66408 | [
-0.02006191574037075,
-0.03224531188607216,
-0.009685861878097057,
-0.050186075270175934,
-0.017964385449886322,
-0.04093167930841446,
0.027131380513310432,
-0.015418385155498981,
-0.0008781703072600067,
-0.04844465106725693,
0.00959683395922184,
0.0252302885055542,
0.019525445997714996,
0... |
<p>I am implementing Markov chain first order non-homogeneous. I have to calculate the probability that the agent is doing an activity given that he was doing another activity in the previous step to compose the probability transition matrix of each step.</p>
<p>Now I want to develop a new method in which I calculate ... | g66409 | [
-0.0009141790797002614,
-0.0044978610239923,
0.03660178929567337,
-0.0063789295963943005,
0.023881986737251282,
-0.061354897916316986,
0.025378545746207237,
0.043988101184368134,
-0.02092031016945839,
-0.0472218319773674,
-0.03300120681524277,
0.04479843005537987,
-0.0033863827120512724,
0... |
<p>I'm trying to do significance test with a set of data <code>X</code> and see if their distribution approximates the population mean <code>M</code>. It's easy to use t-test command <code>ttest(X, M)</code> in MATLAB but it assumes normality. I want a significance test that does pretty much the same thing but just doe... | g66410 | [
0.007405090611428022,
0.0387347936630249,
0.003195663681253791,
-0.0590427927672863,
-0.026321763172745705,
-0.016219932585954666,
-0.012488816864788532,
0.01625777781009674,
-0.02334682270884514,
-0.016386233270168304,
0.018194181844592094,
0.0048512667417526245,
-0.005938311107456684,
0.... |
<p>I generally come across scoring in logistic modeling (also other methods like discriminant analysis, etc.). </p>
<p>I want to know what is the use of scoring of individuals after running a logistic regression (or any other method). Can anybody suggest me some literature on the use of scoring?</p> | g66411 | [
-0.0006780862458981574,
-0.004019278101623058,
0.009286442771553993,
-0.04080311581492424,
-0.004173191264271736,
-0.04448911175131798,
0.011614702641963959,
-0.0052236877381801605,
-0.03888668119907379,
-0.009652597829699516,
0.007020283490419388,
0.02388145960867405,
0.08612621575593948,
... |
<h3>Context</h3>
<p>I'm writing a few multiple choice practice questions and I'd like to store them in a simple plain text data format. I've previously used tab delimited, but that makes editing in a text editor a bit awkward. I'd like to use a format a bit like bibtex.</p>
<p>E.g., </p>
<pre><code>@Article{journals... | g39415 | [
0.01263181772083044,
-0.01856868900358677,
-0.008856413885951042,
-0.07976340502500534,
-0.011755872517824173,
-0.04304921254515648,
-0.046561963856220245,
0.020417839288711548,
-0.017508510500192642,
-0.028816109523177147,
0.01980654150247574,
-0.04626930505037308,
0.0717204287648201,
-0.... |
<p>I read wiki article about Apriori. I have the trouble in understanding the prune and Join step. Can anyone explain me how Apriori algorithm works in simple terms(such that Novice like me can understand easily)? </p>
<p>It will be good if someone explains the step by step process involved in it. </p> | g66412 | [
0.03929297253489494,
-0.011156704276800156,
0.015315000899136066,
0.04548390954732895,
0.0020346457604318857,
-0.03155766427516937,
0.02811983786523342,
0.09233471751213074,
-0.0371578074991703,
0.01114508043974638,
-0.021269556134939194,
0.0168474018573761,
0.019685538485646248,
0.0123394... |
<p>I have a binary variable, $X=\{0,1\}$ and I want to use this variable to predict a continuous outcome variable $y$</p>
<p>What regression model ought I use to estimate the predictive ability of $X$ of $y$?</p>
<p>I know that switching them the other way around, would allow me to use a logistic regression model but... | g66413 | [
-0.0038757105357944965,
-0.06103264167904854,
0.0167272686958313,
0.023648042231798172,
0.009168055839836597,
-0.04399677366018295,
0.007150840945541859,
0.03711365908384323,
0.002100415527820587,
-0.04682167246937752,
0.02626958303153515,
0.053899385035037994,
0.023227732628583908,
-0.000... |
<p>If 2 distributions of data have the <strong>same mean value</strong> but <strong>standard deviation</strong> of sample 1 is twice the value of sample 2, explain what the difference in standard deviation value would indicate about the two distributions.</p>
<p>Totally stuck with this one.</p> | g66414 | [
0.034815818071365356,
-0.006282561458647251,
0.008214924484491348,
0.01077466830611229,
-0.010148823261260986,
0.028285056352615356,
-0.01755748875439167,
0.01104840636253357,
-0.009278232231736183,
-0.07592332363128662,
-0.045751750469207764,
0.002806747332215309,
0.055158037692308426,
-0... |
<p>I am doing SNP association study, and the estimated p-values for each SNP are plotted as a QQ-plot. The question is, can one interpret false positive hits from a QQ-plot in GWAS (Genome-Wide Association Study)?</p>
<p>From this article: <a href="http://www.genomesunzipped.org/2010/07/how-to-read-a-genome-wide-assoc... | g66415 | [
0.0002931124472524971,
-0.0018033608794212341,
-0.005827159155160189,
-0.051005613058805466,
-0.04663098603487015,
0.0031497799791395664,
-0.002302075270563364,
-0.004155069123953581,
-0.0008388142450712621,
-0.006568112410604954,
0.005769609473645687,
-0.007473185192793608,
0.03770276531577... |
<p>Exercise 5.1 from Myers' "Classical and modern regression with applications" asks you to prove that:</p>
<p>The regression coefficient associated with $X_{j}$ in the multiple regression of $y$ against $(X_{1}, \ldots,X_{n})$ is equal to the slope of the regression of
$e_{y/X_{-j}} $ against $e_{x_{j}/X_{-j}}$ </p... | g25407 | [
0.014481309801340103,
-0.03432627394795418,
-0.003434898564592004,
-0.0024966199416667223,
0.04678481072187424,
-0.08269646018743515,
0.013161650858819485,
0.04063450172543526,
-0.03552889823913574,
0.021681420505046844,
-0.03955959156155586,
0.027383185923099518,
0.01778339222073555,
0.01... |
<p>Generally I have seen that pre and post intervention tests are applied on the same sample from a population undergoing an intervention. e.g. same set of students may be tested in an educational intervention in both pre and post tests.</p>
<p>Would it be valid to test different random samples in both the pre and pos... | g66416 | [
-0.01678185909986496,
-0.027402248233556747,
0.05214079096913338,
-0.017006978392601013,
-0.013383660465478897,
0.0036260944325476885,
0.011294601485133171,
0.055232126265764236,
0.05643882602453232,
-0.0033663511276245117,
0.04631767049431801,
0.017861967906355858,
-0.034780796617269516,
... |
<p>I wonder what the difference between multivariate standard normal distribution and Gaussian copula is since when I look at the density function they seem the same to me.</p>
<p>My issue is why the Gaussian copula is introduced or what benefit the Gaussian copula generates or what its superiority is when Gaussian co... | g66417 | [
0.032219842076301575,
-0.02972871996462345,
0.006106643937528133,
-0.043419841676950455,
-0.013512779027223587,
0.03410082310438156,
0.03000400774180889,
-0.0031610745936632156,
-0.026378296315670013,
-0.004172275774180889,
-0.02252122014760971,
-0.01630396768450737,
0.023934612050652504,
... |
<p>Suppose we have an outcome variable $y_{ji}$ which is a count of behaviors performed by group $j$ in round $i$, for $j = 1,...,n$ and $i = 1,...,8$. The outcome $y_{ji}$ counts are non-independent within each group $j$. Possible values for $y$ are bounded between 0 and 12, and because the behaviors appear to follow ... | g25408 | [
-0.03754008188843727,
-0.0403662770986557,
0.002769042970612645,
0.024478955194354057,
0.016546297818422318,
-0.024136647582054138,
0.02259358949959278,
0.03214464336633682,
-0.03607017546892166,
-0.03865453973412514,
-0.016244586557149887,
0.022576598450541496,
0.021191684529185295,
0.014... |
<p>I am currently trying to transition from R into Python to streamline the process of working in web-based applications. I know that SciKit Learn has a ton of functionalities parallel to R's, including several that are similar to R's caret, but I am much more comfortable using R in general.</p>
<p>I am looking for a ... | g66418 | [
-0.042470674961805344,
-0.04411710053682327,
0.03169344365596771,
-0.059110283851623535,
0.010649619624018669,
-0.02416982874274254,
0.01933792047202587,
-0.07714377343654633,
-0.05719420313835144,
-0.03646732121706009,
-0.02319343015551567,
0.04330895096063614,
0.07920804619789124,
0.0593... |
<p>I am aware that the question about the asymmetry of hypothesis testing is not a new question (and I have done my homework and read about it quite a bit). However, I still do have two questions I would like to adress.</p>
<p>First just my understanding of the asymmetry in hypothesis testing: I understand this proble... | g66419 | [
0.04926284775137901,
0.012174980714917183,
-0.008975372649729252,
0.011460911482572556,
0.04004145786166191,
0.005986909382045269,
0.02526259981095791,
0.053461264818906784,
-0.004236373584717512,
-0.006913919933140278,
0.02646647021174431,
-0.005916082300245762,
0.022210750728845596,
0.06... |
<p>What are some ways that people know to plot a function of three variables, in a way that is relatively easy to understand on paper?</p>
<p>Although this could be generalized to pretty much any scenario, I'm specifically looking at a process where I can control pressure, power, and temperature. My output is a single... | g66420 | [
0.02968912199139595,
-0.00790493469685316,
0.004510624334216118,
-0.050576888024806976,
-0.06382541358470917,
-0.04038585349917412,
-0.024577805772423744,
-0.012689311988651752,
-0.04698886722326279,
-0.0033058305270969868,
0.05275576189160347,
-0.01602436788380146,
0.03160460665822029,
-0... |
<p>I am trying to run a Multiple Regression model but I am not sure what should I do to prepare the data input. In my model the dependent variable is the artificial surfaces in hectares, the independent are the GDP (monetary value) and Population (inhabitants). The histogram shows that the data is not normal distribute... | g66421 | [
0.04159773513674736,
0.016888363286852837,
-0.015123962424695492,
-0.015240386128425598,
-0.006944861728698015,
0.041702304035425186,
-0.009884991683065891,
0.02615184895694256,
-0.014470101334154606,
-0.04215717315673828,
-0.028390254825353622,
0.01669091358780861,
0.04694318398833275,
-0... |
<p>I am doing a project for share repurchase in the US. I am trying to estimate the operating performance before and after the repurchase announcement. And I am trying to adjust the performance to the industry level. The paper saying the results was estimated by the two tailed Wilcoxon test. Regarding this test, could ... | g66422 | [
0.04226480796933174,
-0.03526025637984276,
-0.0091174878180027,
0.005602435674518347,
0.039658721536397934,
-0.05417562648653984,
0.07000595331192017,
0.07448608428239822,
-0.008495558984577656,
0.001246031722985208,
-0.02728031575679779,
0.05776442214846611,
-0.008558947592973709,
0.02795... |
<p>I used PCA to reduce outcome variables (cognitive function) from 5 to 2 factors.
Now can I use these two factors as dependent variables (representing cognitive function) in Spearman correlation matrix and in multiple regression analysis instead of using the original cognitive results?</p> | g25413 | [
0.011393371038138866,
-0.06495495140552521,
0.010655290447175503,
-0.054605863988399506,
-0.010221202857792377,
-0.023118583485484123,
0.11622167378664017,
0.0025560781359672546,
-0.020516667515039444,
-0.04098224267363548,
-0.0024487252812832594,
0.03428944945335388,
0.0063158259727060795,
... |
<p>A student of mine developed a heuristic supervised machine learning algorithm for highly multivariate data. It seems to work pretty well, and once the model has been derived from the training data set, we can represent it as </p>
<p>$X'=X\cdot L$</p>
<p>Where $X$ is the $n \times k$ sample matrix with $n$ samples ... | g25414 | [
-0.006868518888950348,
-0.028950292617082596,
0.001134691876359284,
-0.06476709246635437,
-0.006037516985088587,
-0.04417945072054863,
-0.011406788602471352,
0.02906561642885208,
-0.045114416629076004,
0.04815706983208656,
0.02043687179684639,
0.01296523492783308,
0.06649847328662872,
0.00... |
<p>I have done some extensive googling and I haven't been successful. Say I have 3 independent random variables that are normally distributed with different means, that is, $X_i \sim \mathcal{N}(\mu_i,\sigma_i^2)$ for $i=1,2,3$. How is the sum of them, or the square root of the sum of them distributed? </p>
<p>This qu... | g25415 | [
-0.008110986091196537,
-0.010875262320041656,
-0.03135009855031967,
-0.03925858065485954,
-0.0424506850540638,
0.01751762442290783,
0.0019636224023997784,
0.027983330190181732,
-0.009990875609219074,
0.017895054072141647,
-0.013214814476668835,
0.009355569258332253,
-0.0012123408960178494,
... |
<p>I am not a statistician, but a medical researcher and I have 5 outcomes that I want to identify independent predictor(s) for each using multiple regression. I have many potential variables that could be included in the multiple regression as independent variables (IV).</p>
<p>One colleague advises to run Spearman c... | g66423 | [
0.038034118711948395,
0.01502152532339096,
0.015610141679644585,
-0.006338164675980806,
0.006135543808341026,
-0.01049666665494442,
0.030724134296178818,
0.05152719095349312,
0.017268255352973938,
-0.030538570135831833,
0.015098328702151775,
0.00744699826464057,
-0.006690151058137417,
0.00... |
<p>I want to make a function that does GARCH and ARCH in python for calculating variance. But I only have a general understanding of the model. Are there any good papers that can be recommend to give me a step by step calculation. I am not a statistician or have a econometrics background so it is difficult for me to ge... | g66424 | [
0.017762279137969017,
-0.02850888855755329,
-0.0021328418515622616,
-0.05551517382264137,
0.029118822887539864,
-0.038534797728061676,
0.038888316601514816,
0.007938527502119541,
-0.01916590891778469,
0.014500709250569344,
-0.03674726560711861,
0.062496162950992584,
0.06852918118238449,
-0... |
<p>I'm working on a document clustering application and decided to use Normalized Mutual Information as one of the measures of effectivenes. But I don't really understand how to implement this in that situation. In <a href="http://nlp.stanford.edu/IR-book/html/htmledition/evaluation-of-clustering-1.html" rel="nofollow"... | g66425 | [
-0.02757210098206997,
-0.02859114482998848,
-0.00031419238075613976,
-0.060856886208057404,
0.017649490386247635,
-0.010335897095501423,
-0.009139787405729294,
0.09266891330480576,
-0.059095390141010284,
0.004325884860008955,
0.009009154513478279,
-0.008241327479481697,
0.026006091386079788,... |
<p>I'm looking to understand the difference between the two and grasp in which situations each might be preferred over the other.</p> | g25418 | [
0.06066549941897392,
-0.003624354023486376,
-0.015156137757003307,
0.017930852249264717,
0.022967183962464333,
0.009120199829339981,
0.002312728203833103,
-0.005344347096979618,
0.012835068628191948,
-0.045730266720056534,
0.020390478894114494,
-0.05007067322731018,
0.025289753451943398,
-... |
<p>I will be doing my colloquium and will be using existing questionnaires. I would like to know if there are authors/authorities who say that an existing questionnaire need not be validated.</p>
<p>The questionnaires I will use were already validated and the reliability is good; even their cross-cultural validity and... | g66426 | [
-0.003003310179337859,
-0.00011630017252173275,
0.031139662489295006,
-0.008883260190486908,
0.029514484107494354,
0.01586885191500187,
-0.03364940360188484,
0.02945069596171379,
0.029214927926659584,
0.031645167618989944,
0.03039914183318615,
0.011122663505375385,
0.0006716886418871582,
0... |
<p>I have 4 diet groups (ST, MSG, TFA, MSG+TFA) and the cholesterol levels were checked at 20wk, 32wk and 40wk. From the raw data it is quite clear that MSG+TFA group had high values of cholesterol compared to MSG and TFA taken singly. What I am interested in is whether the higher levels of cholesterol in MSG+TFA group... | g66427 | [
0.003201785497367382,
0.004132422152906656,
-0.0026855815667659044,
0.021988680586218834,
-0.035001154989004135,
-0.017958790063858032,
0.008660112507641315,
0.0047777025029063225,
-0.06355874240398407,
-0.026876790449023247,
-0.02380814030766487,
0.017253350466489792,
0.02695125713944435,
... |
<p>I would like to understand, what is the major implementation difference between standard and spherical k-means clustering algorithms. </p>
<p>In each step, k-means computes distances between element vectors and cluster centroids, and reassigns document to this cluster, whose centroid is the closest one. Then, all c... | g25420 | [
0.038971878588199615,
-0.0740540400147438,
-0.013030844740569592,
0.0490230917930603,
-0.005820350721478462,
-0.008473771624267101,
-0.03831062465906143,
0.06627281755208969,
0.008349270559847355,
0.032238755375146866,
-0.01668943464756012,
-0.003927640151232481,
0.09186360239982605,
-0.02... |
<p>I have a dataset of patient information and I'm looking to find a way to compare two groups of patients and take into account confounding variables. My dataset has an N of ~1500 and I'm looking for a difference between two populations (treated/untreated) and whether they responded to therapy.</p>
<p>I have been usi... | g66428 | [
0.006504836957901716,
-0.04063314571976662,
0.0071479324251413345,
-0.08396216481924057,
-0.016845904290676117,
-0.04882585257291794,
-0.0070188893005251884,
0.028830712661147118,
-0.0386202335357666,
-0.022578679025173187,
0.040359336882829666,
0.027417205274105072,
0.006004557479172945,
... |
<p>I'm fitting a linear model where the response variable is a measure of physical performance-- running speed for example-- and the predictor variables are sex and drug treatment, with an interaction term.</p>
<p>$$Y = \beta_{0}+\beta_1X_{sex}+\beta_1X_{drug}+\beta_3X_{sex}X_{drug}$$</p>
<p>We suspect that body weig... | g39532 | [
0.027656571939587593,
0.03913086652755737,
-0.005041475873440504,
-0.005830467212945223,
0.03505059704184532,
-0.0075401803478598595,
0.04253096505999565,
-0.004811941180378199,
-0.0425332710146904,
-0.008853747509419918,
-0.0001886269892565906,
-0.006912499666213989,
-0.015451290644705296,
... |
<p>I'm working on a Bayesian Regression problem where I would like to estimate the beta coefficients subject to this constraint (penalty):</p>
<p>$\sum|\beta_i|<C$ or similarly $\sum \beta_i^2<C$</p>
<p>Which is basically a Lasso or L2 Penalty.</p>
<p>Now, if I understand correctly, we constrain the coefficien... | g66429 | [
0.0021224694792181253,
0.001589803141541779,
0.007807673886418343,
-0.04577111080288887,
0.018960140645503998,
-0.030179107561707497,
0.04541560634970665,
-0.04338591545820236,
-0.07487791776657104,
-0.00034573368611745536,
-0.038861747831106186,
0.07631886750459671,
0.011571069248020649,
... |
<p>I am using logistic regression to create a credit scorecard from past loan data. We will not approve loans in the future if the applicant has an insufficient credit score (no credit or insufficient data for a score from credit bureaus). </p>
<p>These borrowers were however granted loan approvals in the past; theref... | g66430 | [
0.007631316781044006,
0.019646989181637764,
0.03019130602478981,
-0.022898735478520393,
-0.004840395413339138,
0.03312017768621445,
0.0036134012043476105,
0.03220854327082634,
-0.04852953553199768,
0.005346239544451237,
0.0205292459577322,
0.02565649338066578,
0.008116057142615318,
-0.0132... |
<p>I have 2 areas within the UK, Oswestry and Swansea, which I have got the crime data figures for for my Geography dissertation... I need to compare the two areas to see the difference in crime... I have 24 crime figures from Oswestry, and 36 from Swansea.
Which would be the best way to do this (I am using SPSS) - Chi... | g66431 | [
0.04872061312198639,
-0.05153200775384903,
-0.012301950715482235,
-0.0565875768661499,
0.0030399239622056484,
-0.05795670300722122,
0.014780511148273945,
0.036858320236206055,
-0.0183922927826643,
0.009456733241677284,
0.02890007384121418,
0.04053894057869911,
0.0421169251203537,
-0.024293... |
<p>I am working through Wasserman's <a href="http://www.stat.cmu.edu/~larry/=stat705/Lecture2.pdf" rel="nofollow">lecture notes set 2</a> and I am unable to fill in the missing steps in the derivation of McDiarmid's inequality (p.5). Just like my <a href="http://stats.stackexchange.com/questions/21075/understanding-pro... | g66432 | [
-0.04521910101175308,
-0.00245659495703876,
0.012096187099814415,
-0.03916076198220253,
0.006447309162467718,
0.016431143507361412,
0.04647143557667732,
-0.0014404586981981993,
-0.009300831705331802,
0.0005935897934250534,
-0.05963382124900818,
0.02450413443148136,
-0.01790599524974823,
0.... |
<p>I've implemented an incremental F-test program that evaluates the fit of an unrestricted model $M_{UR}$ against the restricted model $M_R$ using the F statistic $\frac{SSE_{R} - SSE_{UR}}{SSE_{UR}}\frac{n-p-1}{j}$. In this instance, I'm interested in comparing a polynomial with order $p$, against another (the restr... | g2092 | [
-0.013658859767019749,
-0.02471565641462803,
-0.0007101736846379936,
0.011126971803605556,
0.004450805950909853,
-0.04095299169421196,
-0.013084638863801956,
-0.01842329278588295,
0.003291562432423234,
-0.005213284399360418,
0.0311436764895916,
0.020038997754454613,
0.02545556053519249,
0.... |
<p>I've implemented an application that collects some relevant data about certain topics, so for each topic I get a list of strings. I want to make a test to see if the data makes sense.</p>
<p>I thought of making a survey, given the same list items (unsorted) and ask the survey takers to sort them. Then I would see h... | g66433 | [
-0.016068728640675545,
0.017104240134358406,
0.010758805088698864,
-0.07718982547521591,
-0.023415457457304,
-0.01137575414031744,
-0.016303613781929016,
-0.025446482002735138,
-0.04670847952365875,
0.0011656192364171147,
0.04461229592561722,
-0.013903929851949215,
0.016265397891402245,
-0... |
<p>I know that others have asked about robust standard errors (<a href="http://stats.stackexchange.com/questions/43787/robust-standard-errors-in-econometrics">Robust standard errors in econometrics</a> and <a href="http://stats.stackexchange.com/questions/452/always-report-robust-white-standard-errors">Always Report Ro... | g66434 | [
0.07182193547487259,
0.019277255982160568,
-0.0038199080154299736,
-0.02877155691385269,
-0.028492532670497894,
0.016552720218896866,
0.011591830290853977,
0.025250231847167015,
-0.005081126932054758,
0.025705529376864433,
0.08280246704816818,
0.018351024016737938,
0.029134131968021393,
-0... |
<p>I just got the output of my <code>lme</code> (<code>nlme</code>) model called <code>shalit5</code> with syntax: </p>
<pre><code>biomass ~ fyear + protection, random = 1|coast/site
</code></pre>
<p>Both <code>fyear</code> and <code>protection</code> are significant, but I am having trouble plotting the fitted value... | g25426 | [
0.01794845424592495,
-0.009073156863451004,
-0.00001471410087106051,
-0.08844178915023804,
0.029704784974455833,
-0.00923829060047865,
0.008093062788248062,
-0.006728101521730423,
-0.04095792397856712,
-0.005344841629266739,
0.026013143360614777,
0.007686941884458065,
0.09423935413360596,
... |
<p>I want to determine the correlation between the returns of a portfolio with returns of the market (suitable index). To find how the portfolio performs in bear resp. bull markets, I want to calculate the correlation coeffients over different periods when the market is in decline or in rise (is this the correct anton... | g66435 | [
0.012564892880618572,
-0.008217082358896732,
-0.016340000554919243,
0.002299451269209385,
0.033775802701711655,
-0.009837141260504723,
0.06755844503641129,
-0.02496502175927162,
-0.01870308443903923,
0.013652419671416283,
-0.010549699887633324,
0.013279160484671593,
0.05278368294239044,
0.... |
<p>I am looking for a formula I can use in Excel that will provide a risk score from 1 - 10 with 10 being high risk. I have a set of 15 data items (i will add more in future) which are weighted on a scale of 1 - 10 with 10 being most valuable (these weightings are already set).</p>
<p>There are a possible 32767 combin... | g66436 | [
0.034776341170072556,
0.06061135232448578,
-0.008947876282036304,
-0.031518060714006424,
0.03894096240401268,
0.01122785173356533,
-0.017217740416526794,
0.007192182820290327,
-0.09622912853956223,
-0.04581049829721451,
-0.027720613405108452,
0.03125624731183052,
0.04520417004823685,
-0.00... |
<p>I was told that it's possible to run a 2 stage iv regression where the first stage is a probit and the second stage is an OLS. Is it possible use 2sls if the first stage is a probit but th second stage is a probit/poisson?</p> | g25429 | [
-0.005217678379267454,
-0.06218625232577324,
-0.009387952275574207,
-0.0680403783917427,
0.013431108556687832,
-0.03441880643367767,
-0.047134432941675186,
-0.0030128073412925005,
-0.0637609213590622,
-0.022489536553621292,
-0.02184034325182438,
0.025832725688815117,
0.019289566203951836,
... |
<p>This question was motivated, but is separate from, the question I posted here:
<a href="http://stats.stackexchange.com/questions/94026/how-can-i-improve-the-predictive-power-of-this-logistic-regression-model">How can I improve the predictive power of this logistic regression model?</a>.</p>
<p>In that case the 'ca... | g25430 | [
0.016914457082748413,
-0.026574844494462013,
-0.002627911511808634,
-0.00720956502482295,
0.06923246383666992,
-0.08386276662349701,
0.0006900617154315114,
-0.01845691166818142,
-0.0356266163289547,
-0.00431025680154562,
0.020153284072875977,
0.0758248120546341,
0.04461437836289406,
0.0068... |
<p>I have data from an experiment in which participants were randomly assigned to one of two groups and asked a series of opinion questions. One group, the control, was not presented with any additional context beyond a brief introduction and the questions themselves. The other group, the treatment group, was given a t... | g25431 | [
-0.027062837034463882,
-0.023376133292913437,
-0.012551166117191315,
-0.027413442730903625,
0.05268773436546326,
-0.022274743765592575,
0.018440648913383484,
0.00668000802397728,
-0.016564887017011642,
0.0067351036705076694,
0.059326015412807465,
0.04748855531215668,
0.006123619619756937,
... |
<p>In my research (medical education field), I had 32 participants answering a questionnaire consisting of 40 Likert items rating their level of confidence in different aspects of treating a certain disease (1= Not at all confident, 6= Completely confident). The participants then undertook a course, and rated their con... | g38924 | [
0.012590615078806877,
-0.03931685537099838,
0.005171848461031914,
-0.033864688128232956,
0.0042611099779605865,
0.009811141528189182,
-0.012241603806614876,
0.013267984613776207,
-0.013122358359396458,
-0.02027028053998947,
0.0340544655919075,
0.05265570804476738,
0.02093483693897724,
-0.0... |
<p>Given the following:</p>
<ul>
<li>a set of numbers, 1 to 20</li>
<li>four sets of five numbers from the set above (each number used once)</li>
<li>a draw of five different numbers from the first set</li>
</ul>
<p>How would I determine the probability that (at least) 1/2/3/4/5 number(s) will match in any one of the... | g66437 | [
0.008009430021047592,
0.01033744029700756,
0.006391782779246569,
-0.07388156652450562,
0.016190769150853157,
-0.012452195398509502,
0.007428680546581745,
-0.008408616296947002,
-0.04083641618490219,
-0.02386433817446232,
-0.05742570757865906,
-0.002424368867650628,
0.02055574208498001,
-0.... |
<p>If the eigen-decomposition of sample covariance matrix is $S=PDP'$ where $D$ is a diagonal matrix with eigen value of $S$ and $P$ are eigenvectors.</p>
<p>If we define the empirical distribution function of sample eigenvalues as $F = p^{-1}\sum_{i=1}^{p}I_{d_{i} \leq d}$, how can we show that, stieltjes transformat... | g66438 | [
-0.04148770123720169,
-0.012454385869204998,
-0.020698731765151024,
-0.08920596539974213,
0.02737778052687645,
0.0009211134165525436,
0.05228418484330177,
0.0008116699173115194,
-0.005560019984841347,
0.034907110035419464,
-0.008990393951535225,
-0.01566230319440365,
0.042042411863803864,
... |
<p>What are the state-of-the-art methods in record deduplication? Deduplication is also sometimes called: record linkage, entity resolution, identity resolution, merge/purge. I know for example about CBLOCK [1]. </p>
<p>I would appreciate if answers also included references to existing software implementing the method... | g66439 | [
-0.0300856065005064,
0.032137855887413025,
0.014541416428983212,
-0.06472411006689072,
-0.012142966501414776,
-0.09215214848518372,
0.054621413350105286,
0.024254202842712402,
0.013611581176519394,
-0.008774984627962112,
-0.035530973225831985,
-0.052556246519088745,
0.068023681640625,
-0.0... |
<p>I have measured a series of times for discrete events along with a continuous variable.</p>
<p>So essentially I measure a point process $P: t_1, t_2, \dots, t_n$ and values $A_1(t=x_1), A_2(t=x_2), \dots, A_m(t=x_m)$ for the continuous variable $A$.</p>
<p>$A$ is sampled at regular intervals ($x_1, x_2, \dots, x_m... | g66440 | [
0.013948872685432434,
-0.03332290053367615,
-0.018659444525837898,
-0.03405578434467316,
0.014201116748154163,
-0.03793945536017418,
0.015728849917650223,
0.006102516781538725,
0.016590189188718796,
-0.05467832460999489,
-0.02778412401676178,
0.026020681485533714,
0.03544214740395546,
0.03... |
<p>I grabbed an implementation of FuzzyKMeans (FuzzyCMeans) from the nightly build of the Apache Commons Math library, but I now realize I need to use <strong>Cosine Similarity instead of the Euclidean Distance</strong>. Of course, just plugging in Cosine Similarity caused the algorithm to end up in an infinite loop (I... | g25436 | [
0.015579714439809322,
-0.022455831989645958,
0.031847983598709106,
-0.02211705595254898,
0.02530297450721264,
-0.015336393378674984,
-0.006550668738782406,
0.007578961085528135,
-0.03599659353494644,
0.01511383056640625,
-0.020606685429811478,
0.0235358364880085,
0.08766511082649231,
0.061... |
<p>In a regression what is the matrix $(X'X)^{-1}$? what do its interior elements represent? Can anyone tell me which values in a stata regression are represented by $(X'X)^{-1}$?</p> | g25437 | [
-0.023790773004293442,
0.0195373073220253,
-0.028465384617447853,
-0.023468442261219025,
0.03751969337463379,
-0.032781023532152176,
0.03426109626889229,
0.020779836922883987,
-0.03781600296497345,
-0.021623844280838966,
-0.015411408618092537,
0.11549637466669083,
0.009001804515719414,
-0.... |
<p>I have some data where I have tested a binomial random variable under 4 conditions. The null hypothesis is that they all have equal means, alternative hypothesis is that one or more means differ from the others.
What kind of test can I use to compare the means of each condition? Sample size for each condition is qui... | g66441 | [
0.008594064973294735,
-0.030746109783649445,
-0.00944671593606472,
-0.07585769146680832,
-0.016697006300091743,
-0.03967800736427307,
-0.007412423379719257,
-0.06637777388095856,
-0.024890588596463203,
-0.04543676972389221,
0.03472534939646721,
0.0018413057550787926,
-0.0005861632525920868,
... |
<p>anova can be used to test the influence of a factor on an output. </p>
<p>One way anova is used if we are considering only one factor and two ways anova can be used if we are considering two factors. </p>
<p>Suppose to test the hypothesis H0 : a1=a2=a3=0<br>
I would like a simulated example where the one way anov... | g25440 | [
0.05687938630580902,
-0.019222112372517586,
0.03316763788461685,
-0.007150531280785799,
-0.005012324545532465,
-0.01660296693444252,
0.012627217918634415,
0.012048224918544292,
-0.025769565254449844,
-0.005311181303113699,
0.00998461339622736,
0.04830867424607277,
-0.01481134444475174,
0.0... |
<p>I am presented with a linear regression result that yields the following coefficients:</p>
<pre><code>Coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept) 0.627502 0.010139 27.782 < 2e-16 ***
A_num ... | g66442 | [
0.006155563518404961,
-0.02523716352880001,
-0.015286305919289589,
-0.06375992298126221,
0.045058056712150574,
0.016751432791352272,
0.020898818969726562,
0.07380237430334091,
-0.042330410331487656,
-0.07253151386976242,
-0.05042213574051857,
0.03699025139212608,
0.006265581119805574,
-0.0... |
<p>I need to know the difference between a non-linear neuron vs non-linear activation function</p>
<p>AND</p>
<p>linear neuron vs linear activation function.</p> | g9530 | [
-0.007728863507509232,
-0.007754742167890072,
0.021901851519942284,
0.013804569840431213,
0.024053610861301422,
-0.09502442181110382,
0.08009854704141617,
0.023646963760256767,
-0.048182155936956406,
0.0017557130195200443,
-0.04563687741756439,
0.027040988206863403,
0.01727929338812828,
-0... |
<p>I am working on a project trying to predict the antecedents of adoption for a new technology. I am using IBM SPSS software but I am not confident with statistics analysis. </p>
<p>I have 10 independent variables (each of them is formed of 3 likert scale items. I just summed the three items to compute each latent v... | g66443 | [
0.0018730978481471539,
0.015568168833851814,
0.012065978720784187,
-0.05120106413960457,
-0.02819364331662655,
-0.014799237251281738,
0.006363479886204004,
0.01149539090692997,
-0.04009867459535599,
0.001813262701034546,
0.01061432994902134,
0.011335155926644802,
0.03157748654484749,
0.091... |
<ol>
<li>For 5 point Likert scale questions and binary (0 or 1) dependent variable, which regression analysis should I use? Can I use a binary
logistic regression on SPSS?</li>
<li>There are two or three questions to measure one independent
variable. I run a factor analysis after that two questions are tied
together. N... | g66444 | [
0.004428755026310682,
-0.056427180767059326,
0.014247068203985691,
-0.06404504179954529,
-0.002061585895717144,
-0.021000681445002556,
-0.027046645060181618,
-0.0009765169234015048,
-0.045089028775691986,
-0.07289829105138779,
0.03213956207036972,
0.03189875930547714,
0.014207827858626842,
... |
<p>I have 4 treatment groups:</p>
<pre><code>1 control (placebo)
1 with X treatment
1 with Y treatment
1 combination-treatment-group XY
</code></pre>
<p>and I have monitored the individuals (n=10) in each group by measurement of their tumor volume at baseline, day 1, 3, 7, 10 and 14 to see what treatment is best and... | g25443 | [
-0.031332071870565414,
-0.029210297390818596,
-0.024347076192498207,
-0.016765929758548737,
0.005626977887004614,
-0.06447027623653412,
0.08476563543081284,
0.011236531659960747,
-0.05735152214765549,
-0.022703079506754875,
0.0036845183931291103,
0.018489480018615723,
-0.020835021510720253,
... |
<p>Should we calculate Cronbach's alpha instead of KR20/KR21 for measuring the reliability of an achievement test, or a test with dichotomous data?</p> | g66445 | [
-0.004281045403331518,
-0.0716593936085701,
-0.009464647620916367,
0.03158465400338173,
-0.033267997205257416,
0.01614651083946228,
0.031394828110933304,
0.018162086606025696,
0.011546864174306393,
-0.026079609990119934,
0.014988300390541553,
0.0033934556413441896,
0.03229562193155289,
0.0... |
<p>Hopefully this is a question that someone here can answer for me on the nature of decomposing sums of squares from a mixed-effects model fit with <code>lmer</code> (from the <a href="http://cran.r-project.org/web/packages/lme4/index.html">lme4</a> R package).</p>
<p>First off I should say that I am aware of the con... | g66446 | [
-0.019920647144317627,
-0.06086774170398712,
-0.0023076245561242104,
-0.060269493609666824,
-0.04198827967047691,
0.03717799484729767,
0.08475164324045181,
-0.0050990162417292595,
-0.009598811157047749,
-0.007904735393822193,
-0.016831930726766586,
-0.01631932333111763,
0.03855528309941292,
... |
<p>We are currently looking to mimic the <code>SPSS Modeler's</code> C5.0 Node decision tree model with boosting, which means we'd like to rewrite the whole thing in plain Java. I was searching the internet hoping to find some description of this algorithm, but with no success. Can someone please shed a light on this? ... | g66447 | [
0.01784508489072323,
-0.06099606305360794,
0.0028339377604424953,
-0.06878557801246643,
0.0130543801933527,
-0.07856932282447815,
-0.02958604134619236,
0.05974440276622772,
-0.024771247059106827,
0.00776811083778739,
-0.031488820910453796,
0.01165829412639141,
0.11988744884729385,
0.096976... |
<p>What is the relation between the autocorrelation and the trend? Can a trend exist in a time series of independent variables? And in time series with a non-zero autocorrelation, does a trend always exist?</p> | g25444 | [
0.015430137515068054,
0.004742673132568598,
0.029629051685333252,
-0.034601740539073944,
0.0036957375705242157,
0.021897394210100174,
0.0035185457672923803,
0.023237647488713264,
-0.029247498139739037,
-0.04925281181931496,
-0.04427333548665047,
0.027599239721894264,
-0.046633679419755936,
... |
<p>I have access to unnnormalized density of some distribution and want to estimate covariance matrix for this distribution. However, Monte-Carlo approach doesn't work well in this case. For distribution dimension $3$ for a normal distribution if I increase number of density evaluations norm $\|K - \hat{K}\|_{\infty}$ ... | g66448 | [
-0.0028290164191275835,
0.01072066929191351,
0.009194041602313519,
-0.08152998983860016,
-0.0412382073700428,
0.010474174283444881,
-0.002608838491141796,
-0.0051188780926167965,
-0.06558918952941895,
0.03947676345705986,
0.03065500408411026,
-0.0027378785889595747,
0.03288447856903076,
0.... |
<p>There is clear meaning of <em>Pearson product-moment correlation coefficient</em>:</p>
<blockquote>
<p>it is cosine of angle between two vectors based on variables. </p>
</blockquote>
<p>Also there are <a href="http://mres.gmu.edu/readings/PSYC557/Rodgers_Nicewander_13ways_look_at_correlation.pdf" rel="nofollow"... | g66449 | [
0.03270525857806206,
-0.045948877930641174,
-0.011622524820268154,
-0.06895169615745544,
0.021611526608467102,
-0.04572038725018501,
0.009275859221816063,
-0.005913908127695322,
-0.014195178635418415,
0.02708376571536064,
0.02528310939669609,
0.003084680764004588,
0.02655905671417713,
-0.0... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.