question stringlengths 37 38.8k | group_id stringlengths 2 6 | sentence_embeddings listlengths 768 768 |
|---|---|---|
<p>Testing for uniformity is something common, however I wonder what are the methods to do it for a multidimensional cloud of points.</p> | g17313 | [
0.02009378932416439,
-0.0037212891038507223,
-0.009840629063546658,
-0.05870799347758293,
0.0037240982055664062,
-0.04477645829319954,
0.010403611697256565,
-0.013270406052470207,
-0.021251728758215904,
0.03578142076730728,
-0.004209326114505529,
0.007174992002546787,
0.08069781959056854,
... |
<p>I think linear regression could handle this but I am asking myself if that method has good statistical power.</p>
<p>Let's think of circles with different radii and let there be points inside those circles.</p>
<pre><code> radius points
Circle A 20 8
Circle 1 10 7
Circle 2 25 ... | g46969 | [
0.014865397475659847,
-0.013147649355232716,
-0.007031430955976248,
-0.041493166238069534,
-0.001621100353077054,
-0.059416886419057846,
0.054865505546331406,
0.00271589495241642,
-0.027975957840681076,
-0.025295384228229523,
-0.005773608107119799,
0.0596681572496891,
0.056415122002363205,
... |
<p>I have a problem in which 4 groups of people are compared in their performance on a certain test. One way anova shows that they are in fact different. But I also know that my groups are different in some other covariate (e.g. age). I'd like to see that if those differences are still significant if I "adjust" for age... | g60953 | [
-0.059114616364240646,
-0.027890753000974655,
-0.015658022835850716,
-0.03246009722352028,
0.01723678596317768,
0.009028845466673374,
0.04883147031068802,
0.048392653465270996,
-0.030288061127066612,
0.03094729408621788,
-0.005050129257142544,
0.020099032670259476,
-0.005667359102517366,
0... |
<p>Let's say I have a data set which shows me basketball players: list of their games which contains date, number of shots they took and number of shots they scored. For example:</p>
<p>1.10.1992 Michael Jordan took 12 shots - scored 6</p>
<p>I would like to predict what is going to be their scoring success rates in ... | g28046 | [
-0.0013534787576645613,
-0.011029643937945366,
-0.004613446071743965,
-0.03734873607754707,
-0.020896058529615402,
-0.024966344237327576,
0.03122168779373169,
-0.03577549755573273,
-0.021967826411128044,
-0.051935404539108276,
0.026364179328083992,
0.054493267089128494,
0.08812907338142395,
... |
<p>Is there a way to do dimensionality reduction on a <strong>binary matrix</strong>. From what I know, Principal Components Analysis does not work. Any suggestions on this matter.</p>
<p>Edit: It's not a symmetric matrix.</p> | g60954 | [
-0.012096610851585865,
-0.01898830011487007,
0.026368940249085426,
-0.037916816771030426,
-0.005127749405801296,
-0.037608902901411057,
-0.011284854263067245,
0.08091269433498383,
-0.036854829639196396,
-0.013534680008888245,
0.02106848731637001,
0.029915103688836098,
-0.005704263690859079,
... |
<p>Can somebody help me to understand a topic? Say in my analysis I have the true variable <em>education</em> ($E$) which is measured by a proxy variable <em>number of years in school</em> ($S$). Here, the error is measurement is $E-S$.</p>
<p>I was told that, this error is independent of $S$ not of $E$.</p>
<p>I can... | g17316 | [
0.0331561453640461,
0.0035279938019812107,
-0.010747522115707397,
-0.0038896859623491764,
-0.01403539814054966,
0.0429595485329628,
0.03328511863946915,
0.021678712218999863,
0.031016936525702477,
0.03891313076019287,
-0.022825652733445168,
0.019786342978477478,
0.032674990594387054,
0.005... |
<p>I have a program generating purportedly normal distributions and I would like to test it. I have a number of issues; perhaps the experts here will help me sort out the essential from the inessential and answer most of these.</p>
<ol>
<li>I'm looking for a simple test, ideally -- one I can implement without too muc... | g60955 | [
0.011768692173063755,
0.033686380833387375,
-0.0030043376609683037,
-0.07402161508798599,
-0.0565490685403347,
0.00015560159226879478,
0.030064743012189865,
0.008876471780240536,
-0.027883319184184074,
-0.05054596811532974,
0.022986751049757004,
-0.008981423452496529,
0.013261768035590649,
... |
<p>I am trying to decide on the correct technique for a multivariate regression with spatial data. I would like to run a regression where the dependent variable is the current snow depth and the independent variables include physiographic parameters (slope, aspect, elevation, etc.) and snow depth for the same site in p... | g47021 | [
0.055030979216098785,
-0.05796492472290993,
-0.0007503250963054597,
-0.031074371188879013,
-0.045487191528081894,
0.05766383931040764,
0.026779182255268097,
0.008640521205961704,
-0.057054679840803146,
-0.006281807087361813,
-0.0021776403300464153,
0.01742352731525898,
0.052636366337537766,
... |
<p>I have a bunch of bivariate correlation tests for which $R$ has already been calculated.</p>
<p>Is it possible to figure out the p-value for each $R$ knowing only (in addition) the number of data points $n$? If not, then what else do I need to know and how do I calculate it?</p>
<p>(I also have results for bivari... | g17319 | [
0.005379468202590942,
-0.000973175629042089,
-0.019763968884944916,
-0.029735391959547997,
0.042654942721128464,
-0.08909032493829727,
0.023611845448613167,
0.014525117352604866,
-0.04430081322789192,
-0.05436068773269653,
-0.04351578652858734,
0.04363191872835159,
0.01828722655773163,
0.0... |
<p>Regarding multiple comparisons, could someone please explain me why the power of false discovery rate (FDR) is greater than the power of family-wise error rate (FWER)?</p> | g60956 | [
0.04918302595615387,
-0.024376988410949707,
-0.01589098572731018,
-0.005851447116583586,
-0.0005995124811306596,
-0.04820236191153526,
0.03198684751987457,
-0.03146274760365486,
-0.06550320982933044,
-0.05899161100387573,
0.018473507836461067,
-0.03324906900525093,
0.013998757116496563,
0.... |
<p>I have data which looks like:</p>
<p><img src="http://i.stack.imgur.com/lB6Yh.png" alt="Figure"></p>
<p>I tried to apply normal distribution (kernel density estimation works better, but I don't need such great precision) on it and it works quite well. Density plot makes a ellipse.</p>
<p>I need to get that ellips... | g26518 | [
0.03969404846429825,
0.026786895468831062,
-0.0016209189780056477,
-0.02880760096013546,
-0.031229054555296898,
-0.038973260670900345,
0.03369205817580223,
-0.011974960565567017,
-0.06844422221183777,
0.0006009626085869968,
0.04483427107334137,
0.042579542845487595,
0.058691106736660004,
-... |
<p>A multinomial distribution can be given as</p>
<p>$ M(m_1,\dots,m_K|N,P) = {N \choose m_1\dots m_K}\prod_k p_k^{m_k} $</p>
<p>The expected value is $Np_k$.</p>
<p>How can I prove it?</p> | g60957 | [
0.0021643112413585186,
0.028620418161153793,
-0.01962454617023468,
0.0019231194164603949,
-0.002611002419143915,
-0.040501974523067474,
-0.03725208342075348,
-0.02254626713693142,
0.034508220851421356,
0.011823077686131,
-0.0315973237156868,
0.005701072514057159,
0.0065481713972985744,
0.0... |
<p>In simulating iterative decoding of low-density parity-check codes there may be (for a certain signal-to-noise-ratio of a noisy channel) for example 10 decoding failures out of $10^6$ trials. The log of probability of decoding failure is plotted against signal-to-noise-ratio.</p>
<p>I quote from the Appendix of Mac... | g60958 | [
-0.003478019032627344,
-0.007203289773315191,
-0.01457270234823227,
-0.029883012175559998,
0.0028067308012396097,
-0.05702764168381691,
0.05071139335632324,
-0.022719603031873703,
-0.05462335795164108,
-0.028715724125504494,
-0.006942777428776026,
0.059240370988845825,
0.04592467099428177,
... |
<p>For Lasso regression $L(\beta)=(X\beta-y)'(X\beta-y)+\lambda*norm(\beta,1)$, suppose the best solution (minimum testing error for example) selects $k$ features, so that $\hat{\beta}^{lasso}=\left(\hat{\beta}_1^{lasso},\hat{\beta}_2^{lasso},...,\hat{\beta}_k^{lasso},0,...0\right)$. We know $\left(\hat{\beta}_1^{lasso... | g60959 | [
0.002056238939985633,
-0.06271259486675262,
0.012094159610569477,
0.015563564375042915,
0.04174582660198212,
-0.043542828410863876,
0.020413341000676155,
-0.006652016658335924,
-0.02470085397362709,
0.010182092897593975,
-0.03045574016869068,
0.06945635378360748,
0.02341552823781967,
0.074... |
<p>Some of you might have read this nice paper:</p>
<p>O’Hara RB, Kotze DJ (2010) Do not log-transform count data. Methods in Ecology and Evolution 1:118–122. <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.2041-210X.2010.00021.x/pdf">klick</a>.</p>
<p>In my field of research (ecotoxicology) we're dealing with ... | g17323 | [
0.014023911207914352,
-0.023839568719267845,
-0.01652960479259491,
-0.037146758288145065,
0.048977967351675034,
-0.0010025122901424766,
-0.03802267089486122,
0.012614001519978046,
-0.0804624930024147,
0.002021055668592453,
0.017901474609971046,
0.011546552181243896,
0.04643123969435692,
-0... |
<p>I'm no statistician, but I do find the area of mathematics fun and fascinating. I have a friend who has designed a "roll-mid" dice system for his custom tabletop RPG and as part of the game balancing, I'm interesting in finding out certain result possibilities.</p>
<p>An individual die has the following results:</p... | g17324 | [
-0.017744064331054688,
0.03185291215777397,
-0.014338918030261993,
-0.05099944397807121,
-0.019302979111671448,
-0.0721181258559227,
0.054285481572151184,
-0.0017290434334427118,
-0.001345336902886629,
-0.016477754339575768,
-0.012837168760597706,
-0.014665120281279087,
0.07440464943647385,
... |
<p>I am estimating sales with data on customer and store locations and attributes using a Huff-style model, where sales decay with drive time and increase with attractiveness of the store.</p>
<p>One hypothetical instance of the problem is illustrated below. The 3 pushpins represent stores and the white flag represent... | g47026 | [
-0.00008492163760820404,
0.08069691807031631,
-0.01972386986017227,
-0.047862373292446136,
-0.00809587724506855,
0.007076798006892204,
0.04461265727877617,
-0.007663600146770477,
-0.04786166548728943,
0.024800939485430717,
0.016597768291831017,
-0.011294730938971043,
0.05077580735087395,
0... |
<p>Given:</p>
<ol>
<li>A coin with <strong>unknown</strong> bias $p$ (Head).</li>
<li>A strictly positive <strong>real</strong> $a > 0$.</li>
</ol>
<p>Problem:</p>
<p>Generate a random Bernoulli variate with bias $p^{a}$.</p>
<p>Does anyone know how to do this? For instance, when $a$ is a positive integer, then ... | g60960 | [
-0.005803585518151522,
-0.01705821417272091,
-0.0030198772437870502,
-0.10312452912330627,
-0.015298682264983654,
-0.048920225352048874,
-0.027709411457180977,
0.007597510237246752,
0.0018935793777927756,
-0.018918367102742195,
-0.00623408192768693,
0.09547492116689682,
0.0380982868373394,
... |
<p>I am proposing a study for a dissertation paper. The paper has 1 dependent variable, and 4 independent variables. The variables are all measured over a 4 year period. The data is quantitative, ratio data. What statistical analysis can be run that uses such a small sample. I have received several different respo... | g60961 | [
0.043304912745952606,
-0.0518251396715641,
-0.020815515890717506,
-0.021567557007074356,
-0.081859290599823,
-0.01869582012295723,
0.008381440304219723,
-0.02135603502392769,
-0.014565019868314266,
-0.011916940100491047,
0.04855653643608093,
-0.002530935686081648,
-0.00815591961145401,
-0.... |
<p>I am a total novice, but I think what I'm looking for is help with an optimization problem. </p>
<p>I have a set of about 26 items, each with a certain value. I want to distribute these items into 8 groups as equally as possible, having granted that a perfectly equal distribution is not possible because of the indi... | g60962 | [
-0.02258935384452343,
0.017706912010908127,
-0.01055892463773489,
-0.013620483689010143,
-0.031989965587854385,
-0.04160941392183304,
0.008496307767927647,
0.035053715109825134,
-0.004267087671905756,
-0.003715121652930975,
0.00315963476896286,
-0.033780597150325775,
-0.011463090777397156,
... |
<p>I recently came upon a discrepancy between Matlab's classify and ClassificationDiscriminant functions. By default, they should both be doing Linear DiscriminantAnalysis, but when given unbalanced classes, they give very different results.</p>
<p>I have created a small test script <a href="https://gist.github.com/dv... | g60963 | [
0.023581409826874733,
-0.043287456035614014,
0.01860688626766205,
-0.03653161600232124,
0.01848457381129265,
-0.024819841608405113,
0.016754986718297005,
0.02357741817831993,
-0.02969743125140667,
-0.07034653425216675,
0.0131960678845644,
0.026619093492627144,
0.06748970597982407,
-0.01699... |
<p>I have lots of sensor data with timestamps like "2014-09-09 16:10:45" and accompanying sensor readings. To get some insight into these I want to find "unusual" events by looking at the average and standard deviation of the time part of the timestamp. How can I handle the wrap-around of time on midnight?</p>
<p>A ma... | g17329 | [
-0.01233471930027008,
-0.03231964260339737,
-0.014097987674176693,
-0.026145292446017265,
-0.05900517478585243,
-0.022905854508280754,
0.019781483337283134,
-0.005151457153260708,
0.004950105212628841,
-0.0003117842716164887,
0.03751060739159584,
-0.04296077787876129,
0.029151950031518936,
... |
<p>I have a simple problem involving probability of drawing at least 1 pair of cards in a four card hand. I am not getting the right answer but I dont understand the flaw in my logic. Can anyone explain to me why my approach is wrong? </p>
<p>The problem:</p>
<p>Bill has a small deck of 12 playing cards made up o... | g60964 | [
-0.014292355626821518,
0.0451972596347332,
0.0024495127145200968,
-0.0025084316730499268,
-0.015943821519613266,
0.01056751050055027,
0.024872809648513794,
0.009687277488410473,
-0.04075505957007408,
-0.02778126858174801,
-0.010007951408624649,
0.004623482935130596,
-0.011100384406745434,
... |
<p>Knowing the distribution,</p>
<p>\begin{array}{c c c c}
& \quad &X=1\quad &X=-1\quad &X=2 \\
&Y=1\quad &0.25\quad &0.25\quad &0 \\
&Y=2\quad &0\quad &0\quad &0.5
\end{array}</p>
<p>How does one calculate E(XY)?</p> | g60965 | [
0.04597948119044304,
-0.00776843773201108,
-0.014794334769248962,
-0.06904099881649017,
0.041655849665403366,
-0.04455440118908882,
0.0243600532412529,
0.02941777929663658,
-0.03343646600842476,
0.037738729268312454,
-0.04712579399347305,
0.019748762249946594,
0.03966152295470238,
0.043556... |
<p>I had a recent question which I probably should re-formulate to a more general one.</p>
<p>I came across this: <a href="http://stats.stackexchange.com/questions/50160/using-scatter-plots-to-understand-multiple-values-of-y-for-a-given-x">Using scatter plots to understand multiple values of Y for a given X</a> and th... | g60966 | [
0.02669087052345276,
0.010867580771446228,
-0.02772904932498932,
-0.07146183401346207,
-0.03907549008727074,
-0.036435600370168686,
-0.014214565977454185,
-0.024668335914611816,
-0.006933045107871294,
-0.03524919971823692,
0.08096900582313538,
0.014632103033363819,
0.10991883277893066,
0.0... |
<p>As of today, dozens of soccer world cup predictions exist, some more complex, some more elegant, and most of them predict every nation's "chance" of winning a particular match/ the cup. </p>
<p>As I am writing a blog post for a newspaper and want to make the statement that these predictions are nice but essentially... | g28051 | [
-0.05044622719287872,
-0.0003130075638182461,
0.01585490070283413,
0.04423855245113373,
0.020541083067655563,
0.0030713765881955624,
0.033197417855262756,
0.06266899406909943,
-0.024665329605340958,
-0.009916162118315697,
0.022288579493761063,
-0.052330244332551956,
0.09010539203882217,
-0... |
<p>I have great difficulty in calculating $\mathrm{E}\left(\sqrt{T_{1} T_{2}}\right)$ where $T_{i}$ is a random variable distributed according to the <a href="https://en.wikipedia.org/wiki/Birnbaum%E2%80%93Saunders_distribution" rel="nofollow">Birnbaum-Saunders distribution</a>. Are there any suggestions on how to ca... | g60967 | [
0.0052079735323786736,
-0.00920837838202715,
-0.026569576933979988,
-0.08612633496522903,
0.003784400876611471,
-0.017518652603030205,
0.0376296229660511,
0.0017369970446452498,
-0.01497640274465084,
-0.00018846294551622123,
0.013389073312282562,
0.019528061151504517,
-0.0024409957695752382,... |
<p>I am trying to calculate a mean and standard deviation from 2 percentiles for a lognormal distribution. </p>
<p>I was successful in performing the calculation for a normal distribution using <code>X = mean + sd * Z</code> and solving for mean and sd.</p>
<p>I think I am missing an equation when I try to do the sam... | g60968 | [
-0.014276688918471336,
0.018056970089673996,
0.008592751808464527,
0.008925172500312328,
-0.03187336027622223,
-0.018931051716208458,
0.019883643835783005,
0.005730442237108946,
-0.01673378050327301,
-0.06647657603025436,
-0.01919621229171753,
0.028729917481541634,
0.04542342200875282,
-0.... |
<p>I have a data set, 1014 cases and 55 variables which are binary and is in the form of </p>
<pre><code>Brand1Attribute1, Brand1Attribute2, ... , Brand1Attribute11, Brand2Attribute1, ... Brand5Attribute11
</code></pre>
<p>with 0 = "No, I do not associate this attribute with this brand" and 1 = "Yes, I associate this... | g17334 | [
0.0063528637401759624,
-0.060299020260572433,
0.001979613211005926,
-0.06867634505033493,
-0.0683155208826065,
-0.03205113112926483,
0.024840155616402626,
0.007902036421000957,
-0.0227226372808218,
-0.03116782382130623,
0.03354917839169502,
0.03003973700106144,
0.08102582395076752,
0.03551... |
<p>I have several photoluminescence emission spectra that I am trying to fit curves to. The spectra each have a slight baseline and four peaks. The independent variable $x_i$ is wavelength (converted to energy for analysis) and the response variable $y_i$ is intensity of light recorded at that wavelength. The experimen... | g17337 | [
0.021431952714920044,
-0.09221100062131882,
-0.0003298825758974999,
-0.02066699229180813,
0.013537404127418995,
0.029498938471078873,
0.015234608203172684,
-0.022529378533363342,
-0.05222788453102112,
-0.00094206677749753,
0.0034372734371572733,
-0.03267645090818405,
0.06229511648416519,
-... |
<p>Recently, I stared working on a machine learning competition hosted on <a href="http://www.kaggle.com/" rel="nofollow">Kagge.com</a>.</p>
<p>As the first step, a quick and dirty system was developed using Logistic Regression (LR). After running the system with increasing the number of training examples step by step... | g60969 | [
-0.024232681840658188,
0.019767217338085175,
0.005315225571393967,
0.006731588393449783,
-0.0064191268756985664,
-0.025121858343482018,
0.02918020635843277,
0.052568186074495316,
0.002886951668187976,
0.04426345229148865,
0.05068287253379822,
0.03041604347527027,
0.0704166442155838,
0.0827... |
<p>I'm using the following data set on some credit scoring models: <a href="https://archive.ics.uci.edu/ml/datasets/Statlog+(German+Credit+Data)" rel="nofollow">https://archive.ics.uci.edu/ml/datasets/Statlog+(German+Credit+Data)</a></p>
<p>My teacher told me that it's best to use the same data set for all the differe... | g60970 | [
-0.020601773634552956,
0.05517733842134476,
-0.00673661520704627,
0.0005458259838633239,
-0.020792989060282707,
-0.03061211109161377,
-0.01949273608624935,
0.0231915395706892,
-0.06327934563159943,
-0.04038693383336067,
-0.011216972954571247,
0.021311093121767044,
0.0500255785882473,
0.048... |
<p>I am new to discrete choice modeling, and I am half way through reading Train's <a href="http://eml.berkeley.edu/books/choice2.html" rel="nofollow">Discrete Choice Methods with Simulation</a>.</p>
<p>My question is: what do I do if some of the choice levels are combined? For instance, if there are choices 1,2,3,4,5... | g60971 | [
-0.03799040615558624,
-0.025451404973864555,
0.002883234294131398,
0.001043451251462102,
0.009467396885156631,
0.006609405856579542,
0.001989860087633133,
-0.010945450514554977,
-0.020444558933377266,
-0.011345718055963516,
-0.03810643032193184,
-0.05026943236589432,
0.08006641268730164,
-... |
<p>I am trying to test whether one group is significantly different from another in two different collections of data. I have seen that people tend to use chi-squared or fisher's exact for this calculation, but am I doing it correctly? Here is the data:</p>
<pre><code> TOTAL NUMBER P... | g60972 | [
0.015336772426962852,
-0.03169266879558563,
-0.0029840630013495684,
-0.0755511224269867,
0.030881037935614586,
-0.06373022496700287,
0.0438280813395977,
0.030536221340298653,
-0.05327889323234558,
0.02104426920413971,
0.06039681285619736,
0.046020545065402985,
0.035691384226083755,
0.02638... |
<p>In my research I have performed a series of measurements on 5 different brands of blocks. Each block has been inspected for deformation under incremental forces (20, 30, 40, 50, 60, 70, 80, 90, 100, 110 and 120 N). The deformation for each force was measured 3 times and the mean values were assigned to each brand fo... | g60973 | [
-0.018198881298303604,
-0.05718429014086723,
-0.002018709434196353,
-0.08341780304908752,
-0.013178501278162003,
-0.015427237376570702,
0.05247269198298454,
-0.04308805614709854,
-0.027907298877835274,
-0.004803918302059174,
0.020210806280374527,
0.03358796611428261,
-0.015401258133351803,
... |
<p>I'm very interested in weather. I use data from weather-stations.
Here are 2 examples of changing <em>average annual temperature</em> in Vienna and Moscow.<br>
(I've got more, but only 2 links allowed ((<br>
<em>LinearModelFit</em> method from Mathematica have been applied (blue lines).<br>
<a href="https://www.drop... | g60974 | [
0.0013542635133489966,
0.0042398180812597275,
-0.0021637415047734976,
0.002606595866382122,
-0.024511732161045074,
0.016311390325427055,
0.04340450093150139,
0.02396313287317753,
-0.049914855509996414,
-0.041870784014463425,
0.025297261774539948,
0.064722940325737,
0.10280939936637878,
0.0... |
<p>I'm taking a spatial stats class, and I'm on the road so I can't ask the prof for help. Would appreciate help understanding what is going on here. </p>
<p>The problem is set up with $Y = X_s'\beta + e$ (with $s$ indexing coordinates). $e$ is assumed to be second-order stationary, with the variogram </p>
<p>$$
\... | g60975 | [
0.051419470459222794,
-0.07163849472999573,
-0.0047447653487324715,
-0.030396729707717896,
0.023716896772384644,
-0.006692315451800823,
0.06340204179286957,
0.02290886454284191,
-0.05346231907606125,
0.02916877157986164,
-0.021954981610178947,
0.07480932027101517,
-0.009154185652732849,
-0... |
<p>I have 25 matrices 19x19 containing coherence measure between EEG electrodes. I want to divided them into some groups by clustering or any other method. I know how to deal with vectors, but I can't find anything about clustering of set of matrices. If it can help - I think we can use coherence as a distance between ... | g60976 | [
-0.016698984429240227,
0.004062458872795105,
-0.021962100639939308,
-0.04562627524137497,
0.035904888063669205,
-0.04794161766767502,
0.040062371641397476,
0.02165146730840206,
-0.019339807331562042,
0.01304391585290432,
0.03505707159638405,
-0.02444763109087944,
0.024622643366456032,
-0.0... |
<p><a href="http://arxiv.org/pdf/cond-mat/0305641" rel="nofollow">"Estimating mutual information"</a> [A Kraskov, H Stögbauer, P Grassberger - Physical Review E, 2004]
states that </p>
<blockquote>
<p>Mutual information is invariant under reparametrization of the marginal variables. If $X ′ = F(X)$ and $Y′ =G(Y)$ a... | g60977 | [
0.009659385308623314,
-0.058165427297353745,
-0.007992072030901909,
0.018160497769713402,
0.019391251727938652,
0.020197702571749687,
0.008470391854643822,
0.024760564789175987,
-0.055771078914403915,
0.033630356192588806,
0.00419944291934371,
0.02751515433192253,
-0.007311384659260511,
-0... |
<p>I have a finite population of transaction data. The data is broken down into various sub-categories.</p>
<p>A subset of these transactions has been audited and determined to either pass or fail.</p>
<p>I want to undertake a logit (and will try probit) regression to make predictions about the un-audited transaction... | g60978 | [
-0.02720779925584793,
0.016513949260115623,
-0.026601482182741165,
-0.0425102561712265,
-0.01889340579509735,
-0.04443248733878136,
0.07620879262685776,
0.04293455928564072,
-0.0259715486317873,
-0.02349141798913479,
-0.0010282015427947044,
0.029252443462610245,
0.07758556306362152,
0.0021... |
<p>From p. 277 of <em>R Cookbook</em>: </p>
<blockquote>
<p>Let's say I have a R model <code>lm(formula = y ~ u + v + w)</code> and the
<code>Summary()</code> shows: </p>
<pre><code>Multiple R-Squared: 0.4981, Adjust R-Squared: 0.4402 F-statistic:
8.603 on 3 and 26 DF, p-value: 0.0003915
</code></pre>
<p>U... | g60979 | [
-0.010008684359490871,
0.04127422347664833,
-0.015784751623868942,
0.025387970730662346,
0.010715534910559654,
-0.046865854412317276,
0.02957039885222912,
0.06488993018865585,
0.00014739633479621261,
-0.04054124280810356,
-0.06013908609747887,
0.032708458602428436,
0.05256129428744316,
0.0... |
<p>I've run a Hierarchical Multiple Regression to understand the unique predictive value of three different maternal variables (maternal PTSD, maternal depression, and quality of the parent-child relationship) in child behavior following trauma exposure (measured by two different subscales of Externalizing behavior pro... | g60980 | [
0.0504930205643177,
0.007916944101452827,
0.008368920534849167,
-0.0014394598547369242,
0.032053764909505844,
0.012333718128502369,
0.0015877290861681104,
0.04937920719385147,
-0.037748176604509354,
-0.07965445518493652,
-0.04567820206284523,
-0.01663687452673912,
0.004926081746816635,
-0.... |
<p>I am trying to set custom orthogonal contrasts for a repeated-measures design using R.</p>
<p>Is it possible to set contrasts just for one factor?</p>
<p>The model looks like this:</p>
<pre><code>lme(percent.diff.mean ~ factor1*factor2*factor3, random = ~ 1|id/factor1/factor2/factor3, data=data, method="ML")
</co... | g60981 | [
-0.04135619103908539,
-0.05069420114159584,
0.002849181881174445,
-0.05093991011381149,
0.014664593152701855,
-0.017609400674700737,
-0.06137371435761452,
-0.017060820013284683,
-0.04573303461074829,
-0.015625888481736183,
-0.053138669580221176,
0.024467645213007927,
0.005110262427479029,
... |
<p>A common good practice in Machine Learning is to do feature normalization or data standardization of the predictor variables, that's it, center the data substracting the mean and normalize it dividing by the variance (or standard deviation too). For self containment and to my understanding we do this to achieve two ... | g60982 | [
0.016964444890618324,
-0.03638531267642975,
0.009612604044377804,
-0.042075756937265396,
-0.029970943927764893,
0.012981617823243141,
0.03635801747441292,
0.07151419669389725,
-0.037892717868089676,
-0.011518372222781181,
0.06309598684310913,
0.016714349389076233,
0.012822083197534084,
0.0... |
<pre><code>a <- c(10,11)
b <- c(2,3)
</code></pre>
<p>The covariance (<code>C</code>) between<code>a</code> and <code>b</code> = </p>
<pre><code>sum ( (a-mean(a)) * (b-mean(b)) ) # equal to cov(a,b) in this case as n=2
</code></pre>
<p>The sample covariance (<code>Csamp</code>) between<code>a</code> and <code... | g17346 | [
0.01390804536640644,
-0.037521153688430786,
-0.001316887908615172,
0.0025528385303914547,
0.0238186065107584,
0.0012884975876659155,
0.08702796697616577,
0.031267110258340836,
0.021227383986115456,
-0.007859309203922749,
-0.0318450890481472,
0.030289465561509132,
0.02626248635351658,
0.003... |
<p><strong>Short version:</strong> How can the joint entropy of two independent variables be less than the sum of those independent variables? The joint entropy should encode all information that a scalar function can, right?</p>
<p><strong>Long version:</strong> Assume there are 2 independent normal random variables ... | g17348 | [
-0.021263953298330307,
-0.0163105595856905,
-0.04243993014097214,
-0.012520244345068932,
-0.002714163390919566,
0.0016305403551086783,
-0.019642312079668045,
0.035510022193193436,
-0.0412028431892395,
0.03990120440721512,
0.010593132115900517,
0.04034262150526047,
0.029523339122533798,
-0.... |
<p>I have a number of sets of time series data. Specifically each set of time series is associated with a single study subject. Each series measures the area between the vocal chords over a breath period (averaged over 10 breaths). Series are recorded for each patient under different dosages of a drug.</p>
<p>I would ... | g17349 | [
0.012992734089493752,
-0.00577708100900054,
-0.001886147540062666,
-0.06328108161687851,
-0.04443413391709328,
-0.07499361038208008,
-0.005711236037313938,
-0.05885491147637367,
-0.031951434910297394,
0.0038663919549435377,
0.026444029062986374,
0.029214750975370407,
0.05974825471639633,
0... |
<p>Could you explain for me what is "likelihood principle (from R.A. Fisher)" without using any (or too serious) mathematical language? What will be the difference between "it is likely" and "it is probable" if we follow this principle?</p> | g49608 | [
0.034233514219522476,
0.004971661139279604,
0.016349483281373978,
0.019065288826823235,
-0.035312119871377945,
0.01449524238705635,
0.018008803948760033,
0.0494927354156971,
-0.02024160698056221,
-0.034768249839544296,
-0.027560396119952202,
-0.00618063285946846,
0.0014628168428316712,
0.0... |
<p>I want to do a logistic regression with R.</p>
<p>I have 18 continuous covariates and a sample consisting of 100 observations.</p>
<p>When I enter all of the covariates into the <code>glm()</code> model, none of them are significant, but the model predicts the outcome perfectly on the test data!</p>
<p>My questio... | g60983 | [
0.00019534955208655447,
0.008739195764064789,
0.006031975150108337,
-0.039834119379520416,
0.060544759035110474,
-0.016036096960306168,
0.009834027849137783,
0.041480135172605515,
-0.08071316033601761,
-0.023208890110254288,
0.03418765589594841,
-0.02818024717271328,
0.027512647211551666,
... |
<p>Over the past few days, I have been conducting some research on self organizing maps for a project at school. I have come to understand that self organizing maps can be used to reduce the dimesionality of your data. However, I do not understand how this works. For example, say you have a 10x10 network of neurons in ... | g60984 | [
-0.024302015081048012,
0.011145485565066338,
0.007151148281991482,
-0.04264427721500397,
0.022027458995580673,
-0.034275203943252563,
0.06285057961940765,
0.08849669992923737,
-0.04312191531062126,
0.0040539042092859745,
-0.04642363265156746,
-0.0040992312133312225,
0.06638166308403015,
0.... |
<p>I have the Kaplan-Meier estimate for the survival function which I obtained using R's survival package:</p>
<pre><code>data.surv <- Surv(data$days_to_event, data$event_flag)
data.fit <- survfit(data.surv ~ 1, data = data)
</code></pre>
<p>The data are censored at 90 days after the initial signal so the surv... | g17353 | [
-0.0091005340218544,
-0.04765501245856285,
-0.004897577688097954,
0.015803968533873558,
-0.003416816471144557,
-0.010036817751824856,
0.06979067623615265,
0.05880682170391083,
-0.07139992713928223,
-0.04711627960205078,
0.0004881231870967895,
-0.0015530586242675781,
0.0559375174343586,
0.0... |
<p>Hi I am new to R and statistics and used to linear models. Can you please explain the output? I used it to make a growth curve.</p>
<pre><code>Formula: length ~ a * (1 - exp(-c * est_age))
Parameters:
Estimate Std. Error t value Pr(>|t|)
a 1.097e+03 1.026e+01 106.966 < 2e-16 ***
c 1.539e-01 1.982e-... | g60985 | [
0.02274165488779545,
-0.025489557534456253,
-0.010829602368175983,
-0.028529372066259384,
-0.01746617630124092,
0.03092276118695736,
0.09065863490104675,
-0.017921488732099533,
-0.07678384333848953,
-0.02400655671954155,
-0.05313090980052948,
0.025861063972115517,
0.06335421651601791,
0.01... |
<p>I'm not a statistician, so I hope this question makes sense. I'm an EMT and we have patients known to be "frequent flyers". Example, we have a diabetic that we have seen 100+ times in 3 years. I have looked over his pattern of calls and it looks like they follow an exponential distribution, which makes sense to me. ... | g26613 | [
-0.005225770175457001,
-0.004617738071829081,
-0.026208486407995224,
-0.021902009844779968,
-0.015795469284057617,
-0.03970658779144287,
0.01518359687179327,
-0.004609063267707825,
-0.00016005852376110852,
-0.050689950585365295,
0.016224760562181473,
0.03551579266786575,
0.09110153466463089,... |
<p>I need some advice regarding my statistical analyses with SPSS.</p>
<p>I have a dataset of temperatures recorded automatically every 30 minutes in three different habitat types for the same time frame. I would like to:</p>
<p>a) assess the differences between these 3 habitat types.</p>
<p>b) compare these 3 habit... | g60986 | [
0.022145360708236694,
-0.07711496204137802,
0.001109950477257371,
-0.03598989546298981,
-0.011989109218120575,
-0.02442924864590168,
-0.007028689607977867,
0.00841720774769783,
-0.04575290158390999,
-0.004089629277586937,
-0.002846275921911001,
0.015835637226700783,
0.010972132906317711,
0... |
<p>I'm trying to predict a response variable in linear regression that should be always positive (cost per click). It's a monetary amount. In adwords, you pay google for clicks on your ads, and a negative number would mean that google pays you when people clicked :P</p>
<p>The predictors are all continuous values. The... | g17356 | [
0.004043531604111195,
0.00913846492767334,
-0.0013414996210485697,
0.004626009147614241,
-0.00007524296961491928,
-0.048223983496427536,
0.03472629189491272,
0.03344760090112686,
-0.04131188616156578,
-0.013865658082067966,
0.04344511404633522,
0.03133125975728035,
-0.02277171052992344,
0.... |
<p>I have a data set that is very large.</p>
<p>The attributes (columns) are several thousand. Some are sparse others are not. Some are ordinal, others interval, nominal or ratio.</p>
<p>The row size is 10s of millions of rows.</p>
<p>The data set is evolving -- that is the business is not sure which rows should fin... | g60987 | [
-0.0070585873909294605,
0.029149653390049934,
-0.03215266019105911,
-0.06269596517086029,
-0.0014018760994076729,
-0.05339745059609413,
0.010486304759979248,
0.013583407737314701,
-0.045212626457214355,
-0.010075082071125507,
-0.07043732702732086,
0.04458693414926529,
0.03118959814310074,
... |
<p>Suppose I have a mixed model like this: </p>
<pre><code>set.seed(123)
require(lme4)
df<-data.frame(id=rep(LETTERS[1:3],each=4),
days=as.integer(rnorm(12,100,10)),
event=rbinom(12,1,0.3))
df<-df[with(df,order(id,days)),]
df$event[sample(1:12,3,T)]<-NA
id days event
1 A ... | g60988 | [
-0.008810673840343952,
-0.04844922944903374,
-0.01881486549973488,
-0.04395277798175812,
0.04570593312382698,
-0.04217497259378433,
0.05790146812796593,
-0.014610479585826397,
-0.02022089809179306,
-0.05302906408905983,
-0.024135615676641464,
-0.011547518894076347,
0.05709044635295868,
-0.... |
<p>What book would you recommend for scientists who are not statisticians?</p>
<p>Clear delivery is most appreciated. As well as the explanation of the appropriate techniques and methods for typical tasks: time series analysis, presentation and aggregation of large data sets.</p> | g49417 | [
0.031502801924943924,
0.052176039665937424,
0.0014501888072118163,
-0.04236751049757004,
-0.07644263654947281,
-0.03394974768161774,
0.031235329806804657,
-0.03351831063628197,
-0.017167560756206512,
0.05758989229798317,
0.0501955971121788,
-0.01627565734088421,
0.08498981595039368,
-0.031... |
<p>This is one of my favorites:</p>
<p><img src="http://imgs.xkcd.com/comics/correlation.png" alt="alt text"></p>
<p>One entry per answer. This is in the vein of the Stack Overflow question <em><a href="http://stackoverflow.com/questions/84556/whats-your-favorite-programmer-cartoon">What’s your favorite “programmer” ... | g47050 | [
0.046147651970386505,
0.04487313702702522,
0.01532968319952488,
-0.05124912038445473,
-0.0071760728023946285,
-0.0034444730263203382,
-0.005514432210475206,
-0.05238443985581398,
-0.027251876890659332,
-0.07190597057342529,
-0.030986156314611435,
0.017487429082393646,
-0.018725600093603134,
... |
<p>I can't fit $X$ to a common distribution so currently I just have $X \sim \text{ecdf(sample_data)}$.</p>
<p>How do I calculate the empirical distribution of $\sum(X_1 + ... + X_n)$, given $n$? $X_1$ to $X_n$ are iid.</p>
<p>My sample size is around $6\times10^7$. $n$ needs to be around 10-20.</p>
<p>To give an ex... | g47051 | [
0.018502365797758102,
0.05858312174677849,
-0.01744905300438404,
-0.08343939483165741,
-0.036055441945791245,
-0.012607080861926079,
0.025267064571380615,
-0.0012646622490137815,
-0.024132369086146355,
-0.02244710549712181,
-0.03345995768904686,
-0.029435692355036736,
0.022499509155750275,
... |
<p><a href="http://arxiv.org/pdf/1109.0161v1.pdf" rel="nofollow">This article</a> uses the following form of the chi-squared test:</p>
<p>$\chi^2=\sum\limits_{i}\frac{(m_i-n_i)^2}{m_i+n_i}$</p>
<p>where $m_i$ is the number of counts of bin $i$ in a <strong>modeled histogram</strong> and $n_i$ the equivalent for the <... | g47179 | [
-0.014027655124664307,
0.03273893892765045,
-0.020067157223820686,
-0.0448586605489254,
0.030481375753879547,
-0.020837821066379547,
0.027187732979655266,
-0.009328369051218033,
-0.03204088285565376,
-0.02509780414402485,
-0.061888135969638824,
0.0064669642597436905,
-0.00046226283302530646,... |
<p>I have some experimental data, and I want to use a non-parametric test to verify my results. I am considering link-prediction on complex networks.</p>
<p>I have a complex network $N$ and an algorithm/model $A$ which finds structure in $N$. I then remove some of the edges in $N$, first $10\%$, then $30\%$ up to $90\... | g37464 | [
0.027661219239234924,
-0.009469063021242619,
-0.016752813011407852,
-0.03745429217815399,
0.049454957246780396,
-0.07718564569950104,
0.05088953301310539,
-0.008039293810725212,
0.0023787803947925568,
-0.014395877718925476,
-0.01829773560166359,
0.004495225381106138,
-0.004649619106203318,
... |
<p>I am taking a course on Maximum Entropy Inference (MEI), where its application to k-Means was discussed. I am confused about the problem setting.</p>
<p>As far as I understand, our goal is to find clustering solutions $c(\cdot)$ with small expected cost $\mathbb{E}[R^{km}(c)] \le R_{max}$. We are therefore interest... | g47181 | [
0.005867601837962866,
0.006516862194985151,
-0.018418122082948685,
0.012183383107185364,
0.0015255744801834226,
-0.029458487406373024,
-0.06558102369308472,
0.04202529042959213,
-0.024215413257479668,
-0.001695243176072836,
-0.03690427541732788,
-0.013418534770607948,
0.0945623517036438,
-... |
<p>I have a load versus capacity problem, and I'm trying to determine the likelihood of failure. Here's a simple example of what I mean. </p>
<p>I have load and capacity discrete pdfs that were determined through a series of computer calculations that analyzed different input values (Monte Carlo simulations to address... | g60989 | [
0.02294415421783924,
0.03696301579475403,
0.000533794576767832,
-0.06320292502641678,
-0.006569262128323317,
-0.04018348827958107,
0.033856648951768875,
-0.052472759038209915,
-0.08732561022043228,
-0.006606780458241701,
-0.007697331253439188,
-0.021118177101016045,
0.08465174585580826,
-0... |
<p>I have done an experiment to test the performance of a system. In this experiment I collected answers from people. These answers are categorical (they were able to select on a 5 points scale). Each subject participated to 2 conditions: in one they are giving evaluations for observations under an ideal situation and ... | g60990 | [
-0.02016056515276432,
-0.01090693473815918,
0.01531894039362669,
-0.0381259024143219,
0.002881281543523073,
-0.04628400877118111,
-0.03353046625852585,
0.03853214532136917,
-0.02722105383872986,
0.016032960265874863,
0.055275194346904755,
-0.007049537263810635,
0.022044837474822998,
0.0625... |
<p>In Hansen and Seo's paper on <a href="http://www.ssc.wisc.edu/~bhansen/papers/joe_02.pdf" rel="nofollow">Testing two regime threshold cointegration in VECM</a> (J. Econometrics, 2002; 110:293), the authors proposed a test based on Lagrange Multiplier for testing treshold in model. However, suddenly the model denotes... | g60991 | [
0.05415038391947746,
0.00717796478420496,
-0.006561495829373598,
-0.02917209453880787,
-0.011875823140144348,
-0.0014102697605267167,
0.065638467669487,
0.058142609894275665,
-0.016026630997657776,
0.032849740236997604,
-0.025645257905125618,
0.048206478357315063,
0.008911903016269207,
-0.... |
<p>This is not homework. I am a frequent user on math.stackexchange, but I am learning a bit about time series models and came across this example. Any ideas would be greatly appreciated.</p>
<p>A linear regression model was fit to some time-series data by ordinary least squares. The residuals from the fit were then... | g17367 | [
0.01516158040612936,
-0.09826117008924484,
0.010183976031839848,
-0.04163330793380737,
0.010608131065964699,
-0.015592879615724087,
0.014864019118249416,
-0.005541819613426924,
-0.045161888003349304,
0.0029227272607386112,
0.0043377019464969635,
0.03363698348402977,
0.06827199459075928,
-0... |
<p>I've recently conducted an experiment with two independent variables: musictype and wordtype, measured by response time. 20 participants. I've done a one-way repeated measures ANOVA along with the usual tests of normality, means etc. Do I need to include a t-test? Am I missing any other important tests?</p>
<p>Many... | g60992 | [
-0.02433883585035801,
0.04744966700673103,
-0.01888604462146759,
-0.06434359401464462,
-0.03805716335773468,
-0.027216263115406036,
0.01935955137014389,
0.002196304267272353,
-0.00475625554099679,
0.03001452423632145,
-0.0678425207734108,
0.00016896378656383604,
-0.08580278605222702,
0.056... |
<p>I am running a correlation coefficient test, and the results were: $r = 0.382, p = 2.76 \times 10^{-13}$. So the $r$ value is not that impressive (usually we see $r>.5$), but the $p$-value is still significant. Usually I would think a low $r$ value would mean high $p$-value (no significant correlation), or vice... | g17368 | [
0.028241967782378197,
0.03270476311445236,
-0.021170107647776604,
-0.030905408784747124,
0.0789775401353836,
0.0033672989811748266,
0.058678191155195236,
0.01211235485970974,
-0.009829766117036343,
-0.054461076855659485,
-0.0764884278178215,
0.04919936880469322,
-0.00745807308703661,
-0.03... |
<blockquote>
<p><strong>Possible Duplicate:</strong><br>
<a href="http://stats.stackexchange.com/questions/16390/when-to-use-generalized-estimating-equations-vs-mixed-effects-models">When to use generalized estimating equations vs. mixed effects models?</a> </p>
</blockquote>
<p>I have a dataset from collected ... | g49609 | [
-0.0090492507442832,
-0.050601158291101456,
0.011041046120226383,
0.04002351313829422,
0.0211818665266037,
-0.009325163438916206,
-0.006641993764787912,
0.0226203054189682,
-0.03260739892721176,
0.00021553087572101504,
-0.014944343827664852,
0.0035382332280278206,
0.04649348929524422,
0.06... |
<p>I've developed a logit model to be applied to six different sets of cross-sectional data. All the models have same independent variables but the sample size is different for each model. What I'm trying to test is the impact of each independent variable on dependent variable across all the models say for example inco... | g47277 | [
-0.01964532397687435,
-0.04311230033636093,
-0.01707262173295021,
-0.014721175655722618,
-0.04192231595516205,
-0.03577781096100807,
-0.0023242069873958826,
-0.01764751970767975,
-0.026497969403862953,
0.0020849297288805246,
-0.0280257947742939,
0.022885993123054504,
0.012300796806812286,
... |
<p>Let $X_1$ and $X_2$ be two independent Normal variables with mean $\theta$ and variance $1$. Let $S=X_1+X_2$ and consider the following conditional probability:</p>
<p>$$P \left[ X_1 \leq x_1; X_2 \leq x_2 |S=s \right]$$</p>
<p>If we assume that $x_1 \leq x_2$ and $x_2 \leq s$, then why does this conditional proba... | g60993 | [
0.044727426022291183,
0.014065349474549294,
0.012204451486468315,
-0.024941828101873398,
0.0504516139626503,
0.03957817703485489,
-0.028818940743803978,
0.05756404623389244,
-0.046693481504917145,
-0.0519656278192997,
0.0030155018903315067,
0.03459465503692627,
-0.0365004763007164,
0.00226... |
<p><strong>I have a question about a very basic classification problem.</strong></p>
<p>The objective is to discriminate between feature A and B.
Where A is a specific biological sample, and B all others.
And the goal is to classify new unknown samples.</p>
<p>To do so I have 12 variables with binary data, represent... | g47067 | [
0.07506421208381653,
-0.06142384931445122,
0.019367579370737076,
-0.02027530036866665,
-0.012874675914645195,
-0.03970363736152649,
-0.02503035217523575,
0.06306688487529755,
-0.018832100555300713,
-0.01836409606039524,
-0.007136279251426458,
0.09918425232172012,
0.022299595177173615,
0.02... |
<p>Through error analysis I found that a quite effective feature actually has bugs in its implementation. Correcting the bugs actually decreased the classifier's performance.</p>
<p>What do you do? Correct the bugs, or leave them there?</p> | g60994 | [
0.04269341751933098,
-0.08452547341585159,
0.01967019774019718,
-0.027224048972129822,
0.06822045147418976,
-0.026947779580950737,
0.054127804934978485,
0.04964186251163483,
-0.021449187770485878,
-0.015219071879982948,
-0.014872467145323753,
0.05069231241941452,
0.002430410822853446,
0.11... |
<p>I have run a stepwise regression and found that some of the selected variables are not significant yet in a multiple regression with all variables included in the model those variables were significant. What can be the cause of this and which results would you recommend that I use?</p> | g17372 | [
-0.03463886305689812,
-0.025257928296923637,
0.012977507896721363,
-0.0008649627561680973,
0.03615892678499222,
-0.0027184386271983385,
0.012971801683306694,
0.08386977016925812,
-0.007338561117649078,
-0.022494006901979446,
-0.015104807913303375,
-0.03688810020685196,
0.0102276261895895,
... |
<p>I have two waterbodies that were sampled for a single water quality variable over time. Both waterbodies were sampled in the fall of each year from 2009-2012. In each year of sampling, 5 replicate samples were taken (so I would have 20 samples in total for each waterbody). I want to compare the two waterbodies over ... | g17373 | [
0.03843928128480911,
-0.030897069722414017,
0.014029363170266151,
-0.04020925983786583,
-0.060893215239048004,
0.02232157252728939,
0.03444333001971245,
-0.03709225356578827,
-0.014615841209888458,
0.012888464145362377,
0.007913912646472454,
0.01113172061741352,
0.01675262674689293,
0.0417... |
<p>I'm fitting a Bayesian Hierarchical logistic model with a random intercept, having data at two levels: subjects and hospital,</p>
<p>logit$(p_{ij})=a_{j}+\beta_{0}+\beta_{1}X_{1i}+\cdots+\beta_{k}X_{ki}+\epsilon_{ij}$</p>
<p>$a_{j}\sim\text{Normal}(\hat{a}_{j},\sigma_{a})$</p>
<p>$\hat{a}_{j}=\gamma_{0}+\gamma_{1... | g6762 | [
0.0186323169618845,
-0.05618039518594742,
-0.009678786620497704,
-0.0651329979300499,
0.001243902137503028,
-0.02635720744729042,
0.015968218445777893,
0.0024356937501579523,
-0.008805464021861553,
-0.00148738210555166,
0.021889226511120796,
0.08503617346286774,
-0.01901400461792946,
-0.02... |
<p>I have a problem interpreting the output of the mixed model procedure in <code>SPSS</code>. I found a couple of threads dealing with similar problems, but none helped me solve it.
I have a 2x2 repeated measures crossover design with two fixed factors (medication (A/B) and genotype (A/B)) and a random factor (timepo... | g17377 | [
0.001610491075553,
-0.08700313419103622,
-0.002765274839475751,
-0.0647827610373497,
0.008895752020180225,
0.00600435258820653,
0.053712550550699234,
0.0063398852944374084,
-0.027199944481253624,
0.018378010019659996,
-0.027162516489624977,
0.009316850453615189,
0.028319166973233223,
-0.00... |
<p>Forgive me if this answer is already somewhere on this site, but after extensive searching I have found nothing to help me. Here is a brief overview of the experiment:</p>
<ul>
<li>I have 18 tanks, each of which are split into 4 sections, each section has a different specie of wetland plant. Tank is my whole plot f... | g17378 | [
0.013465574942529202,
-0.0722314640879631,
0.0018714190227910876,
-0.03666974976658821,
0.004487524274736643,
0.016385722905397415,
0.05486871674656868,
0.03780776262283325,
-0.05880444869399071,
-0.01582415960729122,
-0.008648342452943325,
0.01811591535806656,
0.024127943441271782,
0.0107... |
<p>I have conducted repeated measures ANOVA, with 2 factors: One within factor (<code>time</code>, pre-post intervention) and one between factor (<code>treatment</code>, two groups). I have measured different dependent variables. I find in all the cases an effect of the within factor, an effect of the between factor, a... | g60995 | [
-0.031780339777469635,
0.0012372133787721395,
-0.022638102993369102,
-0.034482840448617935,
0.03703542798757553,
0.0071537732146680355,
0.03492026776075363,
0.02452479861676693,
-0.025972401723265648,
0.029062410816550255,
-0.04757251963019371,
0.018729189410805702,
-0.011676741763949394,
... |
<p>Suppose an invigilator suspects one student of copying answers off another student's paper during a multiple-choice exam. She later checks their answers and finds some similarities—but on the other hand, there are bound to be similarities given the nature of the exam. How should she go about determining whether her ... | g60996 | [
0.004069842863827944,
-0.042365677654743195,
0.006336108781397343,
0.0037274621427059174,
-0.06593279540538788,
-0.0030797834042459726,
0.044060323387384415,
-0.0023703863844275475,
0.01395372860133648,
0.0030366142746061087,
-0.02489284612238407,
-0.01459945272654295,
0.025331934913992882,
... |
<p>I am building a non-linear model aiming to describe the mechanistic process of resource allocation. There several terms, and what makes the model non-linear is competition between lines that are facing each other pair by pair.</p>
<p>I tested the significance of terms through AIC comparisons, deleting non significa... | g17380 | [
0.03494785353541374,
-0.005885267164558172,
0.003082828363403678,
0.008292663842439651,
0.032638069242239,
-0.05436322093009949,
0.06971801817417145,
0.02427099272608757,
-0.06398401409387589,
0.07340429723262787,
-0.020495183765888214,
-0.031176889315247536,
0.012177372351288795,
0.038952... |
<p>I am comparing the size distribution of trees in six pairs of plots where one plot received a treatment and the other a control. Using a Kolmogorov-Smirnov test on each pair of plots I find that $p$ ranges from $0.0003707$ to $0.75$. Are there any appropriate methods for dealing with all of the replicates together... | g60997 | [
0.025966458022594452,
-0.034933902323246,
0.0003795620577875525,
-0.0063425651751458645,
-0.08014722913503647,
-0.04544464498758316,
-0.047024961560964584,
0.03715219348669052,
0.015845902264118195,
0.01716386154294014,
0.035624679177999496,
0.007749034091830254,
0.017066650092601776,
0.01... |
<p>I'm building regression models on four the different but related data set and at the end, I want to test the significance of models. Since my models are built in a different data set, it's not comparable. But there are some hierarchy in my dataset. </p>
<p>1) The output in my main dataset is the sum of the outputs ... | g60998 | [
0.04467712342739105,
-0.035350505262613297,
-0.021697089076042175,
-0.03710102289915085,
0.04521433264017105,
-0.04819151759147644,
0.0489644892513752,
0.018553851172327995,
-0.06140994280576706,
-0.01991829089820385,
-0.006537823472172022,
0.051111940294504166,
0.01212056539952755,
0.0067... |
<p>My question is as below:</p>
<p>Random sample $Y_1,\dots, Y_n$ from $N(\mu,\sigma^2)$. Let $\bar{y}=\frac{1}{n}\sum Y_i$.<br>
(1) $(\bar{y}-\,\mu)/\sigma=a'x$ where $x\in R^n$, $x\sim N(0,1)$.<br>
(2) $\sum(y_i-\bar{y})^2=\sigma^2 X'AX$ where $X \sim N(0,1)$.<br>
(3) $\frac{n(\bar{y}-\mu)^2}{\sigma^2}=X'BX$ where ... | g17383 | [
0.0036442535929381847,
-0.02154693566262722,
-0.01956886798143387,
-0.008258648216724396,
0.002139679156243801,
-0.04763692989945412,
0.09602268040180206,
-0.023585088551044464,
0.007951769046485424,
-0.0010990353766828775,
-0.03562232106924057,
0.11134061962366104,
0.011128237470984459,
0... |
<p><strong>The Game</strong></p>
<p>There is a pool of $n$ cards that are marked either by a <code>A</code> or by a <code>B</code>. There is a proportion $p$ of the cards that are marked by a <code>A</code> and a proportion $1-p$ of the cards that are marked by a <code>B</code>. The game is the following. I randomly d... | g60999 | [
0.058180566877126694,
-0.02151632495224476,
-0.031751956790685654,
-0.019083816558122635,
0.012581689283251762,
0.02289191260933876,
0.0012941876193508506,
-0.04358796030282974,
0.006118164397776127,
-0.030416743829846382,
-0.0016153363976627588,
0.042776625603437424,
-0.010230221785604954,
... |
<p>I have no statistics background, but an trying to complete my first quantitative research survey writeup for my researcher in education class and hope someone can direct me.</p>
<p>I created a poll of 62 teachers and am trying to analyze the following 4 questions </p>
<ol>
<li>Do they use social media personally (... | g61000 | [
-0.027544163167476654,
0.04991401359438896,
0.003621188458055258,
-0.009082598611712456,
0.011643650941550732,
0.004490723367780447,
0.04553292319178581,
-0.010766062885522842,
0.027948759496212006,
0.011328165419399738,
0.047567833214998245,
-0.026501713320612907,
0.024755949154496193,
0.... |
<p>Given a p.s.d kernel $Q$, can minimization/maximization of $Tr(X^TQX)$ over X be represented within a reproducing kernel Hilbert space (RKHS) framework? If there is a primary concern with the trace function being unbounded(for maximization) or trivial zero-solution(minimization); you may consider constraints over $... | g61001 | [
-0.016738153994083405,
-0.01503289770334959,
0.0038734660483896732,
-0.012768321670591831,
-0.03196144104003906,
-0.07880505919456482,
-0.02964085340499878,
0.01364810112863779,
-0.03395160287618637,
0.030440332368016243,
-0.008731432259082794,
-0.04367704689502716,
0.08425712585449219,
0.... |
<p>Is it appropriate to conduct an unpaired t-test with only summary means from both groups? </p>
<p>For example, let's say you want to compare:</p>
<p>a. Professor A's scores received on a evaluation by <strong>his</strong> students from one semester; with<br>
b. The average evaluation scores among all professors i... | g61002 | [
-0.02102598547935486,
-0.01664452627301216,
-0.0034790015779435635,
-0.05605123192071915,
-0.017089426517486572,
-0.03182586282491684,
0.02495679259300232,
0.021208979189395905,
-0.03191886842250824,
-0.01012631319463253,
0.05276482179760933,
0.03340690955519676,
0.009838013909757137,
0.05... |
<p>I read that in survival analysis, when the hazard function $$\lambda(t)=\underset { dt\rightarrow 0 }{ lim } \frac { Pr(t\le T<t+dt|T\ge t) }{ dt } =c$$ then the event occurrence is <strong>random</strong> and independent (memoryless). </p>
<p>I can understand the concept and implications of monotonically increa... | g61003 | [
0.01947450265288353,
-0.03820279985666275,
0.0020316760055720806,
-0.02067050337791443,
0.0012291569728404284,
-0.00020463655528146774,
-0.02141100913286209,
0.048642490059137344,
-0.05975472554564476,
-0.043032389134168625,
-0.06520503014326096,
0.030577395111322403,
0.04308166354894638,
... |
<p>This seems like a typical Bayes' Rule question, but I'm having trouble formulating it properly.</p>
<p>Say I'm a speaker on a conference tour which moves from city to city. I'm trying to estimate how many people will attend my talk in the next city, given how many attended in previous cities.</p>
<p>For example, s... | g61004 | [
0.03132319077849388,
0.03469303622841835,
0.0040565491653978825,
-0.06182590126991272,
-0.03475218638777733,
-0.010305038653314114,
0.060931023210287094,
0.08415680378675461,
-0.0630662590265274,
-0.023960942402482033,
-0.02423485554754734,
0.01637703739106655,
0.025672325864434242,
0.0428... |
<p>I am looking for a good software system to teach students on response surface designs with. Few things I can think of are SAS Proc RSReg or SAS ADX. Is there any other software?</p> | g17395 | [
0.013255750760436058,
-0.012528149411082268,
-0.000744237273465842,
-0.03298696503043175,
-0.04728299379348755,
0.016029948368668556,
-0.00787829328328371,
-0.016598843038082123,
0.01853366009891033,
-0.11620181053876877,
0.05036516860127449,
-0.003202936379238963,
0.08078733086585999,
0.0... |
<p>Recently I found that the <code>PROC GLIMMIX</code> procedure in SAS added a statement <code>effect</code>, which can handle B-spline in models. I tried it, and the program looks like:</p>
<pre><code>proc glimmix data=temp;
effect t = spline(time);
model y = x1 x2 t / solution;
random intercept / subjec... | g61005 | [
0.011569224298000336,
0.00826231949031353,
-0.0006126817315816879,
-0.056836262345314026,
-0.02736957184970379,
-0.023132281377911568,
0.01752167008817196,
0.0013792705722153187,
-0.048338666558265686,
-0.04191486909985542,
0.04286893084645271,
0.01785736344754696,
0.0713329166173935,
-0.0... |
<p>In linear regression, I seemed to see (but I forgot where) that if the square sum of residuals divided by square sum of total variation equals the square of some correlation between some random variables, and hence it explains why the ratio is called "R Square". </p>
<p>So I was wondering what the correlation is be... | g49610 | [
0.045414648950099945,
-0.05915726721286774,
-0.012204604223370552,
-0.016278594732284546,
-0.02312946878373623,
-0.011795594356954098,
0.052809376269578934,
0.013118123635649681,
0.024855410680174828,
-0.03815694525837898,
-0.014742964878678322,
0.0020404316019266844,
0.018064096570014954,
... |
<p>I have results from the same test applied to two independent samples:</p>
<pre><code>x <- c(17, 12, 13, 16, 9, 19, 21, 12, 18, 17)
y <- c(10, 6, 15, 9, 8, 11, 8, 16, 13, 7, 5, 14)
</code></pre>
<p>And I want to compute a Wilcoxon rank sum test.</p>
<p>When I calculate the statistic $T_{W}$ by hand, I get:
$... | g61006 | [
0.009592895396053791,
-0.017319301143288612,
-0.025824032723903656,
-0.026154084131121635,
0.04000145569443703,
-0.0559096485376358,
0.03997016325592995,
0.04962550848722458,
-0.016429992392659187,
-0.059077050536870956,
-0.01727984845638275,
0.061413709074258804,
0.024759624153375626,
0.0... |
<p>This is a soft-question:
I have been evaluation various regression techniques over a regression dataset that I have. I am surprised by the fact that cross-validated RMSE of Lasso is better than SVM and Random Forest in my case. Can this happen?- I mean, I believed that a non-linear modeling technique like random for... | g61007 | [
0.02036614716053009,
-0.03272820636630058,
0.015079020522534847,
0.03917567431926727,
-0.006043706089258194,
-0.0008714627474546432,
-0.00034557681647129357,
0.04502659663558006,
-0.04249943420290947,
0.009581456892192364,
0.051390159875154495,
0.007860472425818443,
0.08325616270303726,
-0... |
<p>I am faced with a problem where I have a situation that can be fit with a linear multivariate regression type model. But, there are two types residual error that will occur from the lack of fit. </p>
<p>Right now, my $\mathbf{Y}$ data is uncorrupted by noise source $\mathbf{R}_{2}$, but will be in the "future". ... | g61008 | [
0.04056805744767189,
-0.052086811512708664,
-0.019763436168432236,
-0.011393575929105282,
0.024104539304971695,
0.0005758763290941715,
0.011512004770338535,
0.0089242709800601,
-0.03507211059331894,
0.006674608215689659,
-0.007656929083168507,
0.03431610018014908,
-0.027986060827970505,
-0... |
<p>I am analyzing an experiment that has the following design:</p>
<pre><code> Factor1 Factor2
Level1 Level1
Level2
Level2 Level1.1
Level1.2
Level2
</code></pre>
<p>In other words, Factor2 has different number of levels across Factor1. I'd like to use logistic r... | g61009 | [
-0.0004262844449840486,
-0.0021779288072139025,
0.0280449278652668,
-0.015177893452346325,
0.03672095760703087,
-0.04434579983353615,
0.013084739446640015,
0.01910795457661152,
-0.08934689313173294,
-0.02434457838535309,
0.0026767009403556585,
0.019030990079045296,
0.02651350013911724,
-0.... |
<p>I have a bunch of related datasets. The pearson correlations between pairs of them are typically definitely larger than the spearman correlations. That suggests any correlation is linear, but one might expect that even if the pearson and spearman were the same. What does it mean when there is a definite gap between ... | g61010 | [
0.054853856563568115,
-0.03271901607513428,
-0.005373402964323759,
-0.08367919921875,
0.013452163897454739,
0.028643986210227013,
0.036848463118076324,
0.01327547337859869,
-0.026928169652819633,
-0.050094638019800186,
0.03007141500711441,
-0.0017049050657078624,
0.004960746504366398,
-0.0... |
<p>for example, in a discrete distribution A</p>
<pre><code>P(X) = 0.999 when x = 0
P(X) = 0.001 when x = 1000
E(X) = 1
Var(X) = 1000-1=999
</code></pre>
<p>compared to B</p>
<pre><code>P(X) = 0.6 when x = 0
P(X) = 0.2 when x = 1
P(X) = 0.2/2 when x = 2
P(X) = 0.2/4 when x = 4
P(X) = 0.2/4 when x = 8
E(X) =... | g17403 | [
0.01766246184706688,
-0.004977886099368334,
-0.017791690304875374,
-0.07356565445661545,
0.028310423716902733,
-0.052365493029356,
0.018544930964708328,
-0.019084438681602478,
-0.02186105027794838,
-0.032820988446474075,
0.0031399789731949568,
0.05787813290953636,
0.019091760739684105,
-0.... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.