question stringlengths 37 38.8k | group_id stringlengths 2 6 | sentence_embeddings listlengths 768 768 |
|---|---|---|
<p>The terminology here is a mess. "Structural equation" is about as vague as "architectural bridge" and "Bayesian network" is <a href="http://www.cs.ubc.ca/~murphyk/Bayes/bnintro.html" rel="nofollow">not intrinsically Bayesian</a>. Even better, God-of-causality <a href="http://www.mii.ucla.edu/causality/?p=571" rel=... | g66614 | [
0.04763311892747879,
0.028413303196430206,
-0.005611935164779425,
0.021363163366913795,
0.03216376155614853,
-0.04071378707885742,
0.042135175317525864,
0.04538664221763611,
0.009557586163282394,
-0.029664279893040657,
0.027197178453207016,
0.0005739989574067295,
0.07494860887527466,
0.003... |
<p>This is my very first post on CV so comment if I can improve my post.</p>
<p>I have two webs that sell very similar products and also have a very similar group of customers.</p>
<p>I was trying to prove that concept that "Fast Moving Inventory From Web A Will Also Move Fast on Web B"</p>
<p>I have the daily snaps... | g66615 | [
-0.0070157283917069435,
-0.02545715682208538,
-0.004103484097868204,
-0.0030786916613578796,
-0.005543186329305172,
-0.03539804741740227,
0.1231093779206276,
-0.06597476452589035,
-0.03656691685318947,
-0.015776999294757843,
0.018475962802767754,
0.020495258271694183,
0.04088934138417244,
... |
<p>I have a data set relating to credit defaults. The data set contains around 100 predictors (some categorical and some numeric). I am interested in predicting the time to default, if the person ever defaults. The term of the loan is 36 months, so a person could default at months 1-36, or never. </p>
<p>The problem i... | g66616 | [
0.03973173350095749,
0.0004283258749637753,
-0.005071297287940979,
-0.04575653746724129,
-0.010954157449305058,
-0.05774802714586258,
-0.02428121492266655,
-0.0015433445805683732,
-0.05659419670701027,
-0.010619066655635834,
0.04585864022374153,
0.02615097165107727,
0.07376936823129654,
-0... |
<blockquote>
<blockquote>
<p>A recruiting firm finds that 20% of the applications are fluent in both English and French. Applicants are selected randomly from a pool and interviewed sequentially. Find the probability that at least five applicants are interviewed before finding the first applicant who is fluent in... | g66617 | [
0.03237447515130043,
0.020798316225409508,
0.007927676662802696,
-0.017177032306790352,
0.049609389156103134,
-0.06034383922815323,
0.04641009494662285,
0.04246251657605171,
-0.06264372169971466,
0.042394183576107025,
-0.04206201806664467,
0.05797556787729263,
0.000360929494490847,
-0.0043... |
<p>I recently ran a pilot of an experiment on Amazon's Mechanical Turk. In the experiment, participants read 5 items, and answered a yes/no question about each one. A between-participants factor was manipulated, which I'll call "Intention."</p>
<p>After completing the pilot of the experiment, I attempted to analyze th... | g66618 | [
-0.04996940493583679,
-0.04275587946176529,
-0.011674286797642708,
0.009166697971522808,
0.024149056524038315,
-0.01952863484621048,
0.02604358270764351,
-0.008448813110589981,
-0.05655718967318535,
-0.003131773555651307,
0.03130481764674187,
-0.012024195864796638,
0.0005001415847800672,
0... |
<p>I'm a bit of a stats newbie so take it easy on me if this ends up being somehow trivial. I'm working on a problem that involves parameter estimation for the sum of two independent gamma distributions (which do not necessarily have the same scale or shape parameters.) I'm interested in what would be the most convenie... | g66619 | [
0.015249050222337246,
-0.03125380352139473,
0.01276203989982605,
-0.062207020819187164,
-0.042005714029073715,
-0.02336018718779087,
-0.005493041593581438,
0.019742801785469055,
-0.07282685488462448,
0.03602151945233345,
0.01298745907843113,
-0.011815531179308891,
0.07679817080497742,
0.04... |
<p>I have chemical A concentration measured at various locations from 1993-2010. I have broken the time into 2 periods 1993-2004 and 2005-2010. </p>
<p><strong>How can I test whether the trend line between the two periods significantly differ?</strong></p>
<p>Someone told me to use the t-test. However, I thought th... | g66620 | [
0.010564066469669342,
-0.02109445631504059,
0.01013930980116129,
-0.033748261630535126,
-0.007244884967803955,
0.013680177740752697,
0.031065121293067932,
0.028723912313580513,
-0.051963917911052704,
-0.009648662991821766,
0.007607124280184507,
-0.030161045491695404,
0.02763364091515541,
0... |
<p>I am looking for a method that may be used to classify and 'cluster' some multi-dimensional data gathered from drill holes, to impute some (only partially measured) physical properties of the rocks within the drill holes. The data are (1) categorical qualitative: broadly classified lithology and stratigraphy, and (2... | g66621 | [
0.024151233956217766,
-0.05888332799077034,
-0.009769505821168423,
-0.10441603511571884,
-0.012276526540517807,
0.016342025250196457,
0.04324212670326233,
-0.03425944223999977,
-0.0377839058637619,
0.0423898808658123,
0.03835311532020569,
-0.02623276226222515,
0.07300470024347305,
0.010251... |
<p>I have two sets of equal sized and normally distributed data, which are output from two different experiments. I wish to do a two-sample t-test with these two data sets to see if the results from the two experiments agree.</p>
<p><strong>Is it appropriate to mean (or median) centralize the data sets before doing th... | g17988 | [
0.018159914761781693,
0.0019769645296037197,
0.004667738452553749,
-0.032601650804281235,
-0.005584388040006161,
0.0032873305026441813,
-0.03923393785953522,
0.020619025453925133,
-0.05630858987569809,
-0.015915991738438606,
0.054523129016160965,
0.044377345591783524,
-0.045712318271398544,
... |
<p>This question is with regards to using a test data set to validate an imputed Cox model using R. With a non-imputed data set I would use <code>val.surv()</code> from <code>rms</code>, but I'm not sure how/if I can use it with my multiply imputed data set.</p>
<p>Further explanation:
I created a predictive Cox PH m... | g3527 | [
-0.00024707915144972503,
-0.06828225404024124,
0.02686014026403427,
-0.04302629828453064,
0.02459537610411644,
0.007222839165478945,
0.016055775806307793,
0.02929341048002243,
-0.008341495878994465,
0.01063466165214777,
-0.0000307422669720836,
0.04561135172843933,
0.02116181142628193,
0.02... |
<p>A name: first, possibly a middle, and surname.</p>
<p>I'm curious about how much information you can mine out of a name, using publicly available datasets. I know that you can get the following with anywhere between a low-high probability (depending on the input) using US census data:
1) Gender.
2) Race.</p>
<p>Fa... | g3530 | [
0.008094791322946548,
0.039265453815460205,
-0.008551136590540409,
0.007345204707235098,
0.00366532732732594,
-0.023355824872851372,
-0.0018115212442353368,
0.001862485776655376,
-0.018763959407806396,
-0.01261926256120205,
0.00962553359568119,
0.018333185464143753,
0.04135558381676674,
-0... |
<p>I am new to statistics so I apologize for the simplicity of my question. </p>
<p>I have a bag with 27 numbers inside; I will pull one number out until I get number 17. THe numbers will be returned to the bag after every try so the prob of success will always be 1/27.</p>
<p>I am trying to determine on average how ... | g66622 | [
-0.07517419755458832,
0.02814907394349575,
-0.0002738760376814753,
-0.021000804379582405,
-0.006824653595685959,
-0.025080915540456772,
0.00510474992915988,
-0.01612650230526924,
-0.0634366124868393,
-0.05124953016638756,
-0.014362514950335026,
-0.0631873607635498,
0.008278093300759792,
0.... |
<p>Is there any basic rule on which elements are over a certain threshold (and thus being important for further inspection) and which are below? Or can I set a "random" threshold just as I find it suitable for my current project?</p>
<p><em>Case example:
I have a list of 94 different elements. The most frequent elemen... | g66623 | [
0.0005656075663864613,
0.05934203788638115,
-0.022856993600726128,
-0.02927667647600174,
-0.015284034423530102,
-0.04362943023443222,
0.059334564954042435,
0.0650796890258789,
-0.0068227509036660194,
-0.011769169941544533,
0.014782723039388657,
0.054094962775707245,
-0.008452903479337692,
... |
<p>I am investigating many different kinds of PCA versions, I am trying to find out whether PCR will apply to my analysis thus the question on use of PCR.</p> | g3536 | [
0.038292430341243744,
-0.042963992804288864,
0.027678921818733215,
0.016596278175711632,
0.004242990165948868,
-0.0631435364484787,
0.04555877670645714,
0.014786561951041222,
-0.022447245195508003,
-0.011350629851222038,
0.04701840505003929,
-0.0035838675685226917,
-0.03356523811817169,
0.... |
<p>I am trying to compare the difference between two means with two pairwise samples. Unfortunately, my data are very far of being normal. What test would you recommend to use in this situation? Should I revert to a nonparametric test?</p> | g25733 | [
0.0027677251491695642,
-0.007814226672053337,
0.010030803270637989,
-0.022059939801692963,
-0.0337296687066555,
-0.032544612884521484,
0.005003992933779955,
-0.019379891455173492,
-0.0029658402781933546,
-0.03247356042265892,
0.04401557892560959,
0.034822430461645126,
-0.023254994302988052,
... |
<p>Assume, I have a data set, which is similar to </p>
<pre><code>require(nlme)
?Orthodont
</code></pre>
<p>and my model is </p>
<pre><code>fm2 <- lme(distance ~ age + Sex, data = Orthodont, random = ~ 1)
</code></pre>
<p><strong>How can I use the model fit object <code>fm2</code> to generate several datasets... | g37615 | [
-0.028370432555675507,
-0.02244245633482933,
-0.01194835640490055,
-0.04943295940756798,
-0.026036495342850685,
-0.00790052954107523,
-0.0010630586184561253,
0.014429045841097832,
-0.042839765548706055,
-0.030107155442237854,
-0.053623590618371964,
-0.025751622393727303,
0.05345357209444046,... |
<p>I want to test if my data have a mean equal to zero (Ho: mu=0). The sample size in not large (n=21). My variable is numerical with average -0.10 and sample_sd 0.05. I don't know the population variance. The only test I know to do this, is t-test. I checked for normality using Shapiro Wilks and it gets rejected (ther... | g66624 | [
-0.022792423143982887,
0.003936098888516426,
-0.0008504473371431231,
-0.01542286854237318,
-0.0744461640715599,
-0.015084382146596909,
0.012984084896743298,
0.07206656783819199,
-0.012509268708527088,
-0.0073570674285292625,
0.015242112800478935,
0.03092055581510067,
0.003953713923692703,
... |
<p>I've been using R's <code>lm</code> to do some linear regression, but decided to give <code>MCMCregress</code> a try to get a feel for how it works. As expected, I got basically the same coefficients, but the extra <code>sigma2</code> value puzzles me.</p>
<p>When I do a <code>qqmath</code> plot of the coefficients... | g66625 | [
0.022783350199460983,
-0.05766845867037773,
-0.0178329199552536,
-0.05049674212932587,
0.021446749567985535,
-0.06152871623635292,
0.012115513905882835,
-0.02236686833202839,
-0.04560231417417526,
-0.04875395819544792,
-0.031326260417699814,
0.04672667384147644,
0.053226288408041,
0.010382... |
<p>The normal distribution can be generalized into the multivariate normal distribution.</p>
<p>Can the logistic distribution also be generalized into a similar multivariate distribution?
Is there a multivariate generalization of the logistic distribution which depends on the covariance matrix $\Sigma$, similar to th... | g66626 | [
0.03384622558951378,
0.004687587730586529,
0.010158020071685314,
-0.035797037184238434,
-0.01565137878060341,
0.004865919705480337,
-0.017046483233571053,
-0.02628158964216709,
-0.0016558312345296144,
-0.012143798172473907,
0.06119457259774208,
0.025255614891648293,
-0.001548859290778637,
... |
<p>I'm conducting my bachelor thesis and I need to do research. This morning I received mail from my supervisor and I'm not quite getting wat he wants me to do. I hope someone can help me.</p>
<p>PS: I will try to keep it as simple as possible.</p>
<p><img src="http://i.stack.imgur.com/Y0Sru.png" alt="enter image des... | g25738 | [
0.01912563666701317,
-0.008994605392217636,
-0.006866251118481159,
-0.03462863340973854,
0.011052030138671398,
-0.03968558833003044,
0.015755388885736465,
0.028814900666475296,
-0.019012846052646637,
-0.0011562940198928118,
0.02625960111618042,
0.05047594755887985,
0.04313799366354942,
-0.... |
<p>If one estimates an ML model with eps following a t5 distribution, while the eps are actually standard normally distributed, intuitively I would say the estimated standard errors would be too large. Is my intuition correct or am I missing something? </p>
<p>The reason for my question is that if standard errors are ... | g25739 | [
0.011988733895123005,
-0.02168605849146843,
-0.0014411450829356909,
-0.04615253210067749,
-0.010509404353797436,
0.007955347187817097,
0.024179508909583092,
0.05750199779868126,
-0.08319568634033203,
0.012996119447052479,
-0.017801614478230476,
-0.05756240710616112,
0.05571861192584038,
-0... |
<p>I want to calculate the degree of slope at each point in a time series. Different time series have different scales. The final number should be normalized in the range of +/-90 degrees. Basically, when I plot my time series in Excel, I can see the degree of slope up or down, 0=flat, 70=very steep up, -20=gradual slo... | g66627 | [
0.033081699162721634,
0.006165877915918827,
-0.0121245626360178,
-0.010024922899901867,
0.009311443194746971,
-0.017722349613904953,
0.060454241931438446,
-0.02766028791666031,
-0.045776139944791794,
-0.0020734902936965227,
-0.010039111599326134,
0.051621198654174805,
0.07760396599769592,
... |
<p>I have run a GLM- I have 1 DV and 9 predictors (4 of which being demographic variables such as age, gender etc). Results show that only 5 predictors are significant predictors with an R square of 34.1%. </p>
<p>When I re-run the model after removing the insignificant predictors, I get an R square of 31.5% which is ... | g49646 | [
0.038490355014801025,
-0.03821379318833351,
0.003377689281478524,
-0.011021343059837818,
-0.013657893985509872,
-0.007690395228564739,
0.05063745379447937,
-0.0033645755611360073,
-0.025070058181881905,
-0.02122393622994423,
0.032586246728897095,
0.03812012821435928,
0.023254331201314926,
... |
<p>I am running an experiment in the lab where a variable is measured over time (e.g: 60 seconds)
I run several times the experiment without any disturbance.</p>
<p>Then I run the experiment again by introducing a distrubance in the starting conditions. The trajectory of the variable I am measuring will start in a sim... | g66628 | [
0.04905451834201813,
-0.07567574828863144,
-0.02406841330230236,
-0.062218330800533295,
0.014916511252522469,
-0.06708109378814697,
0.09028374403715134,
-0.002802257426083088,
-0.02279016561806202,
-0.05207064002752304,
0.03941745683550835,
0.028305137529969215,
0.03793884068727493,
0.0720... |
<p>I'm working with an unbalanced panel dataset. (Country-Time) of approximate dimensions H=100 individuals i and average time length over individuals $mean(T_i)\approx7.5$. And about n= 8 regressors (appart from the fixed effects dummies).</p>
<p>I want to use the Durbin-Watson panel generalization from <em>Bhargava,... | g66629 | [
0.016770092770457268,
0.015453509986400604,
-0.015193657018244267,
-0.061402034014463425,
0.013139761053025723,
0.010829447768628597,
0.07018395513296127,
-0.041218191385269165,
-0.02502797730267048,
-0.030318716540932655,
0.014715478755533695,
0.04980618134140968,
0.023776784539222717,
-0... |
<p>I am currently planning a survey. The data will be used to test which of three metrics best captures some "true" underlying characteristic of the respondents. Getting data on the "true" underlying characteristic is costly, so I want a simplified metric that best approximates the "true" measure. </p>
<p>For the curr... | g66630 | [
0.03876839950680733,
0.007230849005281925,
-0.03177312761545181,
-0.03401125594973564,
-0.03387819230556488,
-0.006867279764264822,
0.020873241126537323,
0.01889919303357601,
-0.04363465681672096,
-0.020065389573574066,
0.06421414762735367,
0.010034673847258091,
0.041819892823696136,
-0.02... |
<p>If a multi-class Linear Discriminant Analysis (or I also read Multiple Discriminant Analysis sometimes) is used for dimensionality reduction (or transformation after dimensionality reduction via PCA), I understand that in general a "Z-score normalization" (or standardization) of features won't be necessary, even if ... | g66631 | [
0.0028279239777475595,
-0.02750050649046898,
0.0077438149601221085,
-0.030061956495046616,
-0.027124159038066864,
-0.05371489003300667,
0.027277441695332527,
0.07396245747804642,
-0.029908666387200356,
-0.06406193226575851,
-0.01926322653889656,
0.04417187720537186,
0.06360739469528198,
-0... |
<p>When I read the literature about random intercept, random slope, and random intercept and slope model, I usually see the graph that they have lines for each participant. I do not know how to plot such graph and what this graph is called. </p>
<p>Can anyone give me a link? or could you tell me what function in R can... | g25741 | [
-0.0069471378810703754,
-0.015017134137451649,
-0.021744824945926666,
0.024574801325798035,
-0.007622431498020887,
-0.026434969156980515,
0.05663871392607689,
0.0005781783256679773,
-0.005797437857836485,
-0.04988991469144821,
0.015625987201929092,
0.011280221864581108,
0.02184438146650791,
... |
<p>I am trying to check the assumptions of a two-way ANCOVA.
So in my model I have</p>
<ul>
<li>two factors (F1, F2)</li>
<li>one dummy coded two level covariate (C)</li>
<li>one dependent variable (D)</li>
</ul>
<p>In order to check the assumption of homogeneity of regression slopes I tried
to perform an ANOVA with... | g25742 | [
-0.01032903790473938,
-0.06045934930443764,
-0.014868359081447124,
-0.0247337706387043,
0.035446058958768845,
0.028173236176371574,
0.06856175512075424,
-0.0037561289500445127,
-0.057197049260139465,
0.025198834016919136,
-0.005990476347506046,
0.05586846172809601,
0.03887803852558136,
0.0... |
<p>I am doing a study of two schools, and at each school I am sampling three groups. I am trying to determine why the person chose to go to that school and not another. I will be asking each group various questions about the school and options they may have had for other schools, etc. I want to be able to detect:</p>
... | g66632 | [
-0.02205885574221611,
-0.029370972886681557,
-0.010580302216112614,
-0.0799577534198761,
0.019511092454195023,
-0.05319491773843765,
0.005327929742634296,
0.0245217215269804,
-0.02539156749844551,
-0.004049072973430157,
0.015819065272808075,
0.002082905964925885,
0.036822058260440826,
0.03... |
<p>This question seems related, but the consensus was that the issue had to do scaling the data, which I do prior to training, so I don't think that's the issue:</p>
<ul>
<li><a href="http://stats.stackexchange.com/questions/81609/issue-on-prediction-with-finalmodel-of-randomforest-in-r-using-the-caret-package">Issue ... | g35496 | [
-0.04387347400188446,
-0.03467617928981781,
0.008796563372015953,
-0.03125927224755287,
0.028629910200834274,
-0.01198572013527155,
0.03675301373004913,
0.02853229269385338,
-0.05785119906067848,
-0.013451175764203072,
0.014419198036193848,
0.017583301290869713,
0.04664561152458191,
-0.007... |
<p>In the context of estimating geophysical quantities from remotely sensed data (inverse theory), what do the terms <em>ex ante</em> and <em>ex post</em> mean? For context, see for example <a href="http://www.atmos-chem-phys.net/6/4311/2006/acp-6-4311-2006.html" rel="nofollow">this paper by T. von Clarmann</a> (empha... | g66633 | [
0.028519630432128906,
-0.04491892084479332,
-0.02277342602610588,
-0.0015006265603005886,
0.036388278007507324,
0.044017743319272995,
-0.03127390146255493,
-0.008553952910006046,
-0.08057200163602829,
0.003988133277744055,
-0.023684469982981682,
0.037045035511255264,
0.029075689613819122,
... |
<p>I'm currently writing an spectrogram to be able to plot Audio signals. </p>
<p>So far, I have done the following:</p>
<ul>
<li>Split the data into blocks of <code>256</code> overlap of <code>128</code> </li>
<li>Applied a Hanning window on each block </li>
<li>DFT of each of the blocks </li>
<li>Taken the first ha... | g66634 | [
-0.0007136384956538677,
0.0017912968760356307,
-0.003686406183987856,
-0.08607596158981323,
-0.010434294119477272,
-0.04903491586446762,
0.006167212501168251,
0.05072442442178726,
-0.06087734177708626,
-0.020886611193418503,
0.027704734355211258,
-0.00913188699632883,
0.01894521899521351,
... |
<p>I'm applying a simple genetic algorithm to an optimization problem (I need to find a 4-parameter function's global minimum)</p>
<p>I start the generations run with say <code>100</code> chromosomes which I then evaluate, select, breed (crossover + mutate) and repeat for <code>N_gen</code> generations.</p>
<p>When t... | g66635 | [
0.017620299011468887,
-0.00994056835770607,
-0.0028710649348795414,
0.002633000025525689,
-0.013411998748779297,
0.0009755552746355534,
-0.008186000399291515,
0.0106852687895298,
-0.08013221621513367,
0.022405628114938736,
-0.023350480943918228,
-0.01024751365184784,
0.03821392357349396,
0... |
<p>I recently received the following email, which I paraphrase below:</p>
<blockquote>
<p>I want to do binomial logistic
regression with the data and I have non-normally distributed IVs. I tried doing square root transformation on
the non-normal IVs. This was
successful in normalising the distribution; howev... | g35498 | [
-0.008119744248688221,
0.019138813018798828,
0.001575007103383541,
0.00025740216369740665,
0.014573592692613602,
-0.05500151589512825,
0.0041403695940971375,
0.05388258025050163,
-0.0023292333353310823,
-0.01109859999269247,
0.013216088525950909,
0.031001806259155273,
0.008360801264643669,
... |
<p>In Bishop's PRML book, he says that, overfitting is a problem with ML, and Bayesian can avoid it.</p>
<p>But I think, overfitting is a problem more about model selection, not about the method used to do parameter estimation. That is, suppose I have a data set $D$, which is generated via $$f(x)=sin(x),\;x\in[0,1]$$,... | g66636 | [
0.03403191640973091,
-0.000742165429983288,
0.01607809029519558,
-0.006635197438299656,
-0.010836689732968807,
0.012600596994161606,
0.0017253953265026212,
-0.023207087069749832,
-0.08687589317560196,
0.01146590244024992,
0.0077012693509459496,
-0.02045726217329502,
-0.018779907375574112,
... |
<p>Given a univariate probabilty density function depending on a set of parameters, is there a generic method to estimate these parameters approximately without having to run the full (numerical) maximization of the likelihood given a dataset ? </p>
<p>In the simple case of estimating the mean and standard deviation o... | g66637 | [
-0.00542712677270174,
-0.04811772704124451,
0.00608584051951766,
-0.04006677120923996,
-0.060004930943250656,
-0.024517977610230446,
-0.0352507121860981,
0.05034370720386505,
-0.0746668204665184,
0.018709849566221237,
0.02442318946123123,
-0.057935457676649094,
0.07704224437475204,
-0.0231... |
<p>I would like to ask a question about error correction terms from VECM if I may. I am currently working on a lot of time-series data and one of the questions I would like to address is whether there is some relationship between different time-series. Reading around the subject it seemed to me that testing for cointeg... | g5063 | [
0.06123834103345871,
-0.050142690539360046,
0.001422605011612177,
-0.013982904143631458,
0.016896318644285202,
-0.03843402862548828,
0.07835642993450165,
0.03166969493031502,
-0.04396079480648041,
0.08175424486398697,
-0.06663693487644196,
0.03667377680540085,
0.03448959439992905,
0.013879... |
<p>I'm trying to prepare my datasets for a classification algorithm that I'm testing. It's a tumour classification dataset to be precise, but I'd like to know of techniques that are dataset as well as learning-model agnostic. What would be the most robust technique to deal with outliers, but without having to lose a lo... | g25747 | [
0.022689711302518845,
-0.007227766327559948,
0.0018112215911969543,
-0.009061779826879501,
-0.016256779432296753,
-0.028553616255521774,
0.020567087456583977,
-0.00024603173369541764,
-0.030175236985087395,
0.021486319601535797,
0.040213316679000854,
-0.010603527538478374,
0.0801104307174682... |
<p>I have 3 independent subjects each of whom have one attempt at guessing the number of balls in a hidden tray with 20 compartments. Each subject therefore has to produce 20 guesses, one for each compartment. The number of balls in each compartment is an integer beginning at 0 with no upper limit (although the majorit... | g25748 | [
0.003872588276863098,
0.04090510308742523,
0.0007524220854975283,
-0.08352451771497726,
-0.040229517966508865,
-0.0441516675055027,
0.09554630517959595,
0.005575047805905342,
-0.02814023569226265,
-0.014957425184547901,
-0.043068066239356995,
0.033639490604400635,
0.06502100825309753,
0.03... |
<p>if I have two uniform random variables $X$ and $Y$, and I sample $N$ values for each, what's the probability of getting an $r$ Pearson's correlation coefficient (or Spearman correlation) between them of at least $x$? In other words what is the distribution of the $r$ values in this case?</p>
<p>Similarly, what if ... | g46112 | [
0.026584500446915627,
-0.0567605197429657,
-0.02181565761566162,
-0.04584265127778053,
0.006607005838304758,
-0.0009483137400820851,
0.04523158445954323,
-0.01738554798066616,
0.024324115365743637,
-0.027254711836576462,
0.00583920581266284,
0.03358880802989006,
-0.01756449043750763,
-0.02... |
<p>I am trying to fit a simple linear model with OLS. I have say 4 terms and the number of data points is >>4, so no explicit overfitting. </p>
<p>1) My terms or my independent varibales do have a strong correlation amongs each other
2) They are all positively correlated with my y</p>
<p>My question is that on buildi... | g46114 | [
0.029618944972753525,
-0.02230379544198513,
-0.008370140567421913,
-0.05372188985347748,
0.002838405780494213,
-0.0031376220285892487,
-0.003141135908663273,
0.03203372284770012,
0.033002112060785294,
-0.05537788197398186,
-0.019919464364647865,
-0.006335798650979996,
0.022710531949996948,
... |
<p>I am using R to do some hypothesis testing on a large sample (n=311) and I am getting confused with the results. R returns very different results than I am getting by hand, using the formulas in my text book.</p>
<p>My data is the difference between (what I think) are two paired sets of observations and is summariz... | g25752 | [
0.03002939373254776,
-0.019477032124996185,
-0.030068373307585716,
-0.016918662935495377,
-0.02920600213110447,
-0.023648452013731003,
0.03986359387636185,
0.015717480331659317,
-0.019288185983896255,
-0.05921478942036629,
0.03383667394518852,
0.02614377625286579,
0.016499077901244164,
-0.... |
<p>I was referring to this video lecture <a href="http://videolectures.net/mlss09uk_murray_mcmc/" rel="nofollow">http://videolectures.net/mlss09uk_murray_mcmc/</a> where the speaker had something like this </p>
<p>$$
p(x|D) = \int P(x|\theta,D)P(\theta,D)d\theta
$$</p>
<p>equivalent to</p>
<p>$$
\frac{1}{S}\sum_{s=1... | g25753 | [
0.0018370712641626596,
0.0072507672011852264,
-0.04191593453288078,
-0.05717756226658821,
0.023524323478341103,
-0.010302347131073475,
0.06650993973016739,
0.0034312179777771235,
-0.0052922628819942474,
-0.04030852019786835,
-0.07841185480356216,
0.05470782890915871,
0.06642095744609833,
0... |
<p>If the probability of success is 0.09, how many trials are required to have a probability of at least one success as 1/3 or more?</p> | g66638 | [
-0.04376872628927231,
0.036250222474336624,
0.0037693288177251816,
0.01732412539422512,
0.03304029628634453,
0.005343182012438774,
0.004585560876876116,
0.017142517492175102,
-0.039989203214645386,
0.0063368515111505985,
-0.007110950071364641,
-0.004170464351773262,
0.0164237841963768,
-0.... |
<p>I seeking help in understanding specific values underlying the formula's for the MA(p) model & the AR(q) model. I am attempting to implement the models (building up to the combined ARIMA model) in the programming language Java.</p>
<p>I do not come from an overly mathematical (I'm fairly new to statistics at le... | g66639 | [
-0.01270601898431778,
-0.03698214516043663,
-0.0005209152586758137,
0.001816239906474948,
0.04451718181371689,
0.005640607327222824,
0.06576132029294968,
-0.010690969415009022,
-0.025005927309393883,
0.019682353362441063,
-0.009536881931126118,
0.06678476184606552,
0.06929709762334824,
0.0... |
<p>I want to be able to calculate the distribution of
$$Y = \sum_{i=1}^n\max\{0,X_i\}$$
where the random variable $X_i\sim N(\mu_i,\sigma_i)$. Is the calculation of $f_Y(y)$ possible and if so what is it?</p> | g66640 | [
-0.04066073149442673,
0.014707401394844055,
-0.030739376321434975,
0.012635146267712116,
-0.04674398899078369,
-0.0634983628988266,
-0.009313425980508327,
-0.01689993590116501,
0.010425674729049206,
0.012671063654124737,
-0.05752379074692726,
0.009367844089865685,
0.029758641496300697,
0.0... |
<p>First time question on this site, so please bear with me, thank you:</p>
<p>I have 6 coin-flip-type experiments for which I can calculate 6 binomial p-values. I would now like to calculate the significance of observing at least 4 p-values < 0.05 in six experiments total.</p>
<p>In one approach, I used Fisher's ... | g66641 | [
-0.03428983688354492,
0.06416061520576477,
0.0012563371565192938,
-0.030667612329125404,
0.028888706117868423,
-0.06084883585572243,
0.03019525296986103,
0.04236394912004471,
-0.008556084707379341,
0.016608402132987976,
-0.031396280974149704,
0.005648795049637556,
0.0569828525185585,
-0.02... |
<p>I am trying to write a logistic classifier that will classify text tokens on a web page. One problem I am running into is the fact that their are many more negative instances of the tokens I am trying to classify then positive ones. My question is: what is the ratio of positive training data to negative training I s... | g46116 | [
-0.02991880103945732,
0.02560274302959442,
0.0003890818334184587,
-0.056009020656347275,
0.0011116469977423549,
-0.03274419903755188,
-0.0164980199187994,
0.019419360905885696,
-0.02870240993797779,
0.00332469935528934,
-0.0036969289649277925,
0.021256526932120323,
0.045712776482105255,
0.... |
<blockquote>
<p><strong>Possible Duplicate:</strong><br>
<a href="http://stats.stackexchange.com/questions/16567/how-to-interpret-basic-output-from-a-regression-analysis">How to interpret basic output from a regression analysis?</a> </p>
</blockquote>
<p>I am wondering what does the following stand for: F( 2, 2... | g49756 | [
0.0016089851269498467,
-0.0006180935888551176,
-0.01971329376101494,
-0.032649390399456024,
0.06692969799041748,
-0.038805656135082245,
0.05038894712924957,
0.02784966677427292,
-0.03015265241265297,
-0.06022277846932411,
-0.015182916074991226,
0.04214764013886452,
0.07066816091537476,
-0.... |
<p>The Kolgomorov-Smirnov test, Shapiro test, etc.... all reject the hypothesis that a distribution is normal. Yet when I plot the normal quantiles and and histogram, the data is clearly normal. Maybe because the power of the tests are high? </p>
<p>The sample size is around 650. So shouldn't at least one of these tes... | g49688 | [
0.04535428062081337,
-0.017043570056557655,
0.0023799953050911427,
-0.019644292071461678,
-0.041213806718587875,
0.008598385378718376,
0.0332929752767086,
0.027113139629364014,
0.013558498583734035,
-0.03369441255927086,
0.060712870210409164,
0.014342604205012321,
0.022938894107937813,
0.0... |
<p><strong>Background:</strong></p>
<p>I had a data set containing 212 observations with a lots of missing values. Most of the IVs and DVs are categorical (DVs are ordinal) in nature. There are 3 DVs and about 30 IVs. My intention was to run an ordinal logistic regression. A list-wise deletion keeps only 42 observatio... | g66642 | [
0.03850346431136131,
-0.044682566076517105,
-0.0036700034979730844,
-0.051349565386772156,
0.014064200222492218,
-0.004288420546799898,
-0.0144169507548213,
0.04626048356294632,
0.02344360761344433,
-0.027893392369151115,
0.04150183126330376,
0.046066947281360626,
-0.0000409456406487152,
0... |
<p>I have a dataset that includes 2 dimensions (A, B), each of which has the same two categories (1,2). I fit a model to the data in each of the 4 conditions and get 4 coefficients for a parameter of interest as a result including various stats about them (SE, CI, etc). I want to determine if dimensions A or B produc... | g66643 | [
-0.021473444998264313,
-0.059961359947919846,
-0.011417591013014317,
-0.03680945187807083,
0.011697856709361076,
-0.00009509387018624693,
0.04877742752432823,
-0.014084446243941784,
-0.07536102086305618,
0.0030647823587059975,
-0.0013956449693068862,
0.026449386030435562,
0.05019696429371834... |
<p>I run several simulation studies with R using a MacBook Pro, which has 8 GB of RAM. Unfortunately, some of the simulations cannot be done due to limited memory. My question is how much RAM is needed for large simulations? (For example, each data set has 10000 subjects and needs to generate 1000 datasets). Is 64 GB o... | g66644 | [
-0.016360070556402206,
0.06971314549446106,
0.0028907007072120905,
-0.02121681347489357,
-0.06408765912055969,
0.032343532890081406,
0.01169439498335123,
0.011047079227864742,
-0.03377271443605423,
0.01216640044003725,
-0.03159673884510994,
-0.006326049100607634,
-0.01707450859248638,
-0.0... |
<p>I would like to fit a 3-level hierarchical regression in lmer, however, I don't know how to specify the grouping factor above the second level.
the model would be:</p>
<pre><code>lmer(depedent ~ independent 1 + independent2 + (1|group1)....
</code></pre>
<p>And I would like to specify another group nested within <... | g66645 | [
-0.012238343246281147,
-0.0013029832625761628,
-0.00136523914989084,
-0.02989940531551838,
0.03823525831103325,
-0.002600255887955427,
0.015909623354673386,
0.003952609375119209,
-0.10926052927970886,
-0.03811556100845337,
-0.042691078037023544,
0.06096932291984558,
-0.02257280796766281,
0... |
<p>I was trying to understand when its better to model some random variable as being distributed by a Poisson Distribution or when being modeled as a Binomial Distribution.</p>
<p>I was reading the following article:</p>
<p><a href="http://www.umass.edu/wsp/resources/poisson/" rel="nofollow">http://www.umass.edu/wsp/... | g66646 | [
0.06536336243152618,
0.003865376580506563,
-0.012472577393054962,
-0.015518809668719769,
0.00367653276771307,
-0.04506061598658562,
-0.014308584854006767,
0.032883379608392715,
-0.034289952367544174,
-0.017489954829216003,
0.020813586190342903,
-0.05518164858222008,
0.01558050699532032,
-0... |
<p>I need to fit a generalized Gaussian distribution to a 7-dim cloud of points containing quite a significant number of outliers with high leverage. Do you know any good R package for this job?</p> | g66647 | [
0.01789654605090618,
-0.0010764850303530693,
-0.0191105455160141,
-0.0674889013171196,
-0.052492935210466385,
-0.03943474218249321,
-0.01885874755680561,
-0.020721567794680595,
-0.0317433699965477,
0.003512239782139659,
0.009064781479537487,
0.007670287508517504,
0.010558072477579117,
-0.0... |
<p>What is a good measure of spread for a multivariate normal distribution?</p>
<p>I was thinking about using an average of the component standard deviations; perhaps the trace of the covariance matrix divided by the number of dimensions, or a version of that. Is that any good?</p>
<p>Thanks</p> | g66648 | [
0.039451707154512405,
-0.008333628065884113,
0.007364481687545776,
-0.07709096372127533,
-0.07066618651151657,
0.022204983979463577,
-0.005946229211986065,
0.002132287947461009,
0.013362644240260124,
-0.005841188132762909,
0.0895664393901825,
0.00536787835881114,
-0.004191146232187748,
-0.... |
<p>From "]
Learning Deep Architectures for AI". see: <a href="http://www.iro.umontreal.ca/~lisa/pointeurs/TR1312.pdf" rel="nofollow">http://www.iro.umontreal.ca/~lisa/pointeurs/TR1312.pdf</a> (see section 3.1)</p>
<p>"The local generalization issue is directly connected to the literature on the curse of dimensionality... | g66649 | [
-0.03327147662639618,
0.013057924807071686,
0.02203470841050148,
-0.06317824125289917,
-0.008526939898729324,
-0.023026421666145325,
0.037402182817459106,
0.025173362344503403,
-0.06679072976112366,
-0.003108372911810875,
-0.05035281181335449,
0.03729628771543503,
0.08323024213314056,
0.01... |
<p>I am currently analyzing a data set having to do with oak tree mortality. I am trying to understand the correlation between dead crowns (dead = <code>0</code>, live = <code>1</code>) and the distance to <strong>(1)</strong> nearest dead crown and <strong>(2)</strong> distance to nearest bay tree. (See Below).</p>
<... | g66650 | [
0.01978054828941822,
-0.07963976263999939,
-0.000808673445135355,
-0.04124301299452782,
-0.01699763350188732,
0.028489504009485245,
0.05237305164337158,
-0.014718666672706604,
-0.0333433672785759,
-0.036699727177619934,
0.009029015898704529,
0.020875301212072372,
0.06346405297517776,
-0.06... |
<p>If I have two completely different time series at equally sampled times, but the length of each of these series is different. How do I statistically compare them? Dynamic Time Warping?</p>
<p>Also, as a follow up question. How do I go about this if each time series is of say 12 dimensions?</p> | g66651 | [
0.0462195910513401,
0.00403315806761384,
0.005022944416850805,
-0.03290809690952301,
-0.021287312731146812,
-0.002417168114334345,
-0.026956817135214806,
-0.030995234847068787,
-0.028880158439278603,
0.005797943100333214,
0.017321398481726646,
-0.0008844221592880785,
0.0135347256436944,
0.... |
<p>I have been asked to analyse some data from a clinical trial looking a two methods of measuring blood pressure. I have data from 50 subjects, each with between 2 and 57 measures using each method. </p>
<p>I'm wondering how best to proceed. </p>
<p>Obviously I need a solution that will account for the fact the me... | g66652 | [
0.00816251989454031,
-0.029901888221502304,
-0.004057430196553469,
-0.009613682515919209,
-0.008109664544463158,
-0.04720880091190338,
0.008231605403125286,
-0.023884376510977745,
-0.023786557838320732,
0.009169958531856537,
0.042591843754053116,
0.0030126196797937155,
-0.010237587615847588,... |
<p>Assuming merging process was completed and we have the history of <code>n-1</code> merged clusters (merge two clusters <code>p</code> and <code>q</code> to cluster <code>c = min{p,q}</code>), we are to draw the dendrogram with <code>k</code> leaf nodes (or number of records, whichever is smaller). If <code>k</code> ... | g66653 | [
0.028178658336400986,
0.01838175766170025,
0.01046252902597189,
-0.027749022468924522,
-0.025228722020983696,
-0.06607899069786072,
-0.05573533475399017,
0.005708048585802317,
-0.017829803749918938,
0.012307653203606606,
0.006872997153550386,
-0.03035181388258934,
0.054142531007528305,
-0.... |
<p>I have run a sequence analaysis using the Optimal Matching algorithm. Afterwards, I have clustered the resulting distance matrice using the Ward algorithm and calculated silhouettes as measures of cluster quality and to identify representative sequences. </p>
<p>Now, I am curious whether it is possible to estimate ... | g25765 | [
-0.0034389407373964787,
-0.04746401309967041,
0.002659447956830263,
-0.03060021623969078,
-0.03930618613958359,
-0.04192666709423065,
-0.014029978774487972,
0.037652015686035156,
-0.028705358505249023,
0.05133054405450821,
-0.025790618732571602,
0.03867209702730179,
0.07374454289674759,
-0... |
<p>I am trying to use R to build a time-series model to predict a variable which is only reported on irregular intervals. I have data for independent variables for all time periods (days), however the key dependent variable, reported_UV, is only reported monthly (every 30 or so days).</p>
<p>I am looking for help bui... | g25766 | [
-0.02576255612075329,
-0.03618774935603142,
-0.02483387291431427,
-0.014052117243409157,
-0.052160751074552536,
-0.00094258674653247,
0.023020721971988678,
0.002476089634001255,
0.030056830495595932,
-0.053718436509370804,
0.040848258882761,
0.0024764954578131437,
0.03983517363667488,
0.01... |
<p>I've been studying the Cox Proportional Hazards model, and this question is glossed over in most texts.</p>
<p>Cox proposed fitting the coefficients of the Hazard function using a partial likelihood method, but why not just fit the coefficients of a parametric Survival function using the maximum likelihood method a... | g49319 | [
0.04724191501736641,
-0.06461644917726517,
0.03543416038155556,
0.0013120779767632484,
-0.033057838678359985,
0.023851163685321808,
-0.026806170120835304,
0.038749441504478455,
-0.024558788165450096,
-0.01282220147550106,
-0.001658018329180777,
-0.03944675624370575,
0.11112932860851288,
-0... |
<p>I know Cohen's $\kappa$ for inter-rater reliability is often regarded as a conservative estimation--e.g., Strijbos & al. below, who say</p>
<blockquote>
<p>The higher the number of categories, the smaller the likelihood of chance agreement as opposed to possible deviations. In other words, kappa tends to be m... | g66654 | [
-0.011284347623586655,
0.015683935955166817,
0.021785520017147064,
0.02449888177216053,
-0.0038175403606146574,
0.009965956211090088,
0.037217170000076294,
0.03602863848209381,
-0.08242843300104141,
-0.043269842863082886,
0.004589909687638283,
-0.011262087151408195,
-0.016462145373225212,
... |
<p>I'm having a look at the intraclass correlation coefficient in SPSS.</p>
<p>Data: 17 participants rated two lists of 9 & 7 items from 0 to 5 (0 being unimportant and 5 being very important).</p>
<p>All participants rated all the items and the participants are a sample of a large population.</p>
<p>The followi... | g25770 | [
0.024842647835612297,
-0.005481208674609661,
-0.006425637751817703,
-0.06127835810184479,
0.017939213663339615,
0.015571479685604572,
0.033140309154987335,
0.030317969620227814,
0.012516286224126816,
-0.06755255162715912,
0.03263517841696739,
-0.0294598750770092,
0.03975514695048332,
-0.00... |
<h2>Model and its assumptions</h2>
<p>I'm working on the methodology of a two-way error component model.
Here is the model: </p>
<p>$$y_{jis} = x_{jis} \beta + \upsilon_{jis}$$</p>
<p>$j$ refers to school, $i$ refers to individual and $s$ to tested area / topic (mathematics or English, ...). $J$ is the number of sch... | g506 | [
-0.02014429308474064,
-0.039124563336372375,
-0.02095482125878334,
-0.03575652465224266,
0.02144833281636238,
-0.006858685985207558,
0.05941110476851463,
0.01689286157488823,
0.009478139691054821,
-0.02922804094851017,
0.01926524192094803,
0.06389662623405457,
0.0035964413546025753,
0.0250... |
<p>I have count data for number of call types over an interval of time for multiple animals. What I want is (1) a summary of association between call types (i.e., if X1 is large, X2 is small) and (2) a measure of similarity between the animals "repertoire" or rather pattern in which they call (comparison of correlation... | g66655 | [
0.020587991923093796,
0.00741915637627244,
-0.0363188199698925,
-0.09513157606124878,
0.004547317046672106,
-0.03538089990615845,
0.03834710270166397,
-0.056390177458524704,
-0.051076553761959076,
-0.03297177329659462,
-0.041045304387807846,
0.028078988194465637,
0.05706530064344406,
0.020... |
<p>I haven't been able to find a good answer for this (though I know that there are a few related questions):</p>
<p>How does Amazon determine how to price a product? How does it figure out when to downprice, and by how much? I'm sure that there's some machine learning involved here, but what does it involve?</p>
<p>... | g66656 | [
-0.004710621666163206,
0.03241449594497681,
-0.024938875809311867,
0.018295422196388245,
0.04884181544184685,
-0.027057383209466934,
0.03674696013331413,
0.0000899519000086002,
-0.03953061252832413,
-0.019871123135089874,
-0.01039967779070139,
-0.005083171650767326,
0.08385300636291504,
0.... |
<p>I have 50 control subjects and I would like to get 150 treatment subjects (i.e., a 1:3 ratio between the control and treatment groups) using propensity score matching and a few covariates. After performing the matching I would like to get indices of matched subjects (i.e., indices for both control and treatment grou... | g25773 | [
0.003940490540117025,
-0.06345296651124954,
-0.013584493659436703,
-0.060893211513757706,
-0.011188735254108906,
-0.06599543988704681,
0.025649117305874825,
0.022263186052441597,
0.026632236316800117,
-0.025659047067165375,
0.03109874203801155,
0.029181677848100662,
0.021190276369452477,
-... |
<p>Ultimately I want to estimate a second-order factor structure in AMOS. </p>
<p>As such I am trying to compare the fit of a first-order model in which the first-order factors are (a) constrained to be uncorrelated, and (b) free to correlate. </p>
<p>I am running into two problems when I try to run these models. </p... | g25774 | [
-0.008699459955096245,
-0.0005083289579488337,
0.0057203457690775394,
-0.04675005003809929,
0.025795094668865204,
-0.03177449852228165,
0.04235444590449333,
-0.0461239218711853,
0.0032444095704704523,
-0.05367191508412361,
0.01681065559387207,
-0.02293875440955162,
0.007265570107847452,
0.... |
<p>I am looking to explore using LSA as a dimension reduction technique for some textual data. To be specific I would like to take a matrix of M documents and N n-grams (ie: variables) and then create a smaller set of D variables that accounts for the most of the variance (thus resulting in a MxD matrix). The problem I... | g66657 | [
0.006013323552906513,
-0.02426017075777054,
0.04114464670419693,
-0.08907514810562134,
-0.062255896627902985,
-0.021957114338874817,
0.0639476627111435,
0.005941805895417929,
-0.094530388712883,
-0.031876206398010254,
0.005321425385773182,
0.0005432978505268693,
0.07347561419010162,
0.0294... |
<p>I have a continuous normally distributed outcome variable ($Y$) and $k$ explanatory variables ($X_i$, $i$ is $1 ... k$). The observations in $X$ are rare, but they behave in an additive fashion, so for all the $X$'s in each observation, I sum the observations up, and then I do linear regression of <code>Y ~ the summ... | g66658 | [
-0.0016396831488236785,
-0.0036769737489521503,
-0.02938576228916645,
-0.036157429218292236,
0.009158149361610413,
-0.014586168341338634,
0.016994597390294075,
0.04829148203134537,
-0.007210105657577515,
-0.05497679114341736,
0.013197097927331924,
0.04771101847290993,
0.002552113961428404,
... |
<p>I have a random effects panel data model with 4 variables, 10 years of data and 946 observations describing different financial values for different companies. The panel is balanced. The model looks something like (written without subscripts t for time and j for company): $ln(A)=b0+b1(ln B) + b2 (ln C)...+u$</p>
<p... | g66659 | [
0.0540904700756073,
-0.06050204485654831,
0.0036240736953914165,
-0.04290526360273361,
0.004867363255470991,
-0.0047362796030938625,
0.059267930686473846,
-0.017351455986499786,
-0.02114994265139103,
0.007535453885793686,
0.019923243671655655,
0.04683609679341316,
0.037877801805734634,
0.0... |
<p>I want to use Excel to generate a random correlated $Y$ from a known $X$. From another thread, I found the equation $Y = r\cdot X + E$, where $X$ is standardized and $E$ is a random variable from normal distribution having mean $0$ and $\sigma = \sqrt{(1-r^2)}$. I assume $r$ is the correlation coefficient found us... | g25781 | [
0.032519493252038956,
-0.04106222465634346,
-0.003821471007540822,
-0.03479747474193573,
-0.004724792670458555,
-0.0034030789975076914,
-0.003642244264483452,
0.024825725704431534,
-0.02454891800880432,
-0.004969301633536816,
-0.02718237414956093,
0.02888091839849949,
0.0644526332616806,
-... |
<p>I have event time data for subjects with different categories (A, B, C etc.) yearly observed. To my understanding my data is both right and interval censored (?). </p>
<p>Subjects' category can change from year to year, e.g. A for years 0 to 2, than B from year 3 onwards for subject 1 etc. Each subject can be expos... | g38035 | [
-0.02781977318227291,
-0.0308082178235054,
0.002259528264403343,
-0.0031833958346396685,
-0.021593205630779266,
0.005399004556238651,
0.06903444975614548,
-0.0007207152084447443,
-0.008863361552357674,
0.0218735933303833,
0.009783178567886353,
0.038631293922662735,
0.05662732943892479,
0.0... |
<p>I have a collection of real-world samples that I am trying to model and then forecast.</p>
<p>There are 10 datasets – each has an increasing number of data points (from 1 to 10). The points are equi-distant and each has some percentage of the total allocation for that set. For example, the first set has 1 data po... | g25783 | [
0.018386710435152054,
0.01989801414310932,
-0.014157348312437534,
-0.05623349919915199,
-0.0013397744623944163,
-0.013287177309393883,
-0.008242669515311718,
0.029202992096543312,
-0.07538188248872757,
-0.005523142870515585,
0.02245367504656315,
-0.017823688685894012,
0.08034113049507141,
... |
<p>I have a linear regression and two estimates, say A and B and their standard errors. I need to find the standard error of a ratio A/B [or A/(1-B)]. I guess the main problem is that I don't know the correlation between A and B... I guess that makes this unsolvable, since the correlation plays a major role... correct?... | g38036 | [
0.06981179863214493,
-0.06063796207308769,
0.001338621019385755,
-0.01961064338684082,
0.01868305169045925,
-0.020728418603539467,
-0.012498586438596249,
0.05990059673786163,
-0.04172630235552788,
-0.029360193759202957,
-0.0002460505929775536,
0.01862015202641487,
-0.0030373649206012487,
-... |
<p>I have a number of measurements of a data point which I want to compare to my model. I have the sample mean, sample standard deviation and therefore the SEM. It usually seems fairly obvious to me whether to use the std. dev. or SEM. I think in this case I want to use the std. dev. as I'm comparing my model to my dat... | g66660 | [
0.040566056966781616,
-0.029090983793139458,
-0.026500452309846878,
0.0011708742240443826,
0.01562952995300293,
0.010504386387765408,
0.01933673769235611,
-0.024738598614931107,
-0.02271723560988903,
-0.027438221499323845,
0.044483207166194916,
-0.02530023269355297,
0.05429306998848915,
0.... |
<p>I would like to do classification based on HOG Features using SVM. </p>
<p>I understand that HOG features is the combination of all the histograms in every cell (i.e. it becomes one aggregate histogram).</p>
<p>I extract HOG features using MATLAB code in this <a href="http://www.vlfeat.org/overview/hog.html" rel=... | g66661 | [
0.016941221430897713,
0.024927526712417603,
0.012770494446158409,
-0.04889870807528496,
0.029846759513020515,
-0.07861844450235367,
-0.03592986613512039,
0.09327227622270584,
-0.06143922731280327,
-0.012427794747054577,
-0.019699307158589363,
0.024544287472963333,
0.06102945655584335,
0.03... |
<p>I don't really understand how the columns "xerror" and "rel error" are calculated.
I found out that the printcp() function "gives cross-validation estimates of misclassication error (xerror), standard errors (xstd) of those estimates and the training (resubstitution) estimates (error)".</p>
<p>Here is an example:<... | g46145 | [
-0.014180301688611507,
-0.062147244811058044,
0.0006888441857881844,
-0.015192467719316483,
0.05561773478984833,
-0.04138873890042305,
0.037735715508461,
0.023782959207892418,
-0.06416638195514679,
0.013120317831635475,
-0.04624134674668312,
0.05313755199313164,
0.045265886932611465,
-0.00... |
<p>I guess this is a quite basic question, but I have been struggling with this for quite some time, so I hope someone can help me with this.</p>
<p>I have a model (type is not relevant for now) which includes a linear predictor (LP) that would normally be calculated as:</p>
<pre><code>LP = sum(coefficient1*predictor... | g25784 | [
0.026576923206448555,
-0.0183233805000782,
-0.01586160622537136,
-0.043496500700712204,
-0.005289451684802771,
-0.04269102215766907,
-0.019365180283784866,
0.053943585604429245,
-0.03342282027006149,
0.01714254543185234,
-0.005403249524533749,
0.01726587861776352,
0.07552552968263626,
0.00... |
<p>Let be Statistan a country of approximately 20 million farmers. I want to draw a representative sample of the farmer population in order to survey them, in particular with the goal of capturing their yield (as defined by kilograms per cultivated hectare) and understanding what makes yield varying across the country.... | g66662 | [
0.0030721453949809074,
0.06108752265572548,
-0.0022518651094287634,
-0.017284395173192024,
0.03156764805316925,
0.0094654755666852,
0.03201651945710182,
0.000996840768493712,
0.005664419382810593,
-0.005165075417608023,
0.0454096719622612,
0.024865781888365746,
0.03976760059595108,
0.01447... |
<p>I had to standardize the scores of a variable because the items composing it were measured on different Likert-type scales (5, 6, 7 points). After this, I ran a correlation between this variable and other variables, with which theoretically it is supposed to correlate negatively.
This yielded though a positive corre... | g66663 | [
0.05138860270380974,
-0.0322711355984211,
-0.00996396318078041,
-0.04624094069004059,
0.02809009701013565,
0.043215200304985046,
-0.015069401822984219,
0.050549838691949844,
-0.012014309875667095,
-0.030758608132600784,
-0.020501891151070595,
0.013613070361316204,
-0.014478466473519802,
0.... |
<p>I want to find the parameters of a model which specifies a set of classification probabilities, for say M classes. (I'll use the parameters in another model later.)</p>
<p>Given a set of parameters $\theta$, I can calculate its implied classification probabilities, $\pi(\theta)$, using Monte Carlo integration - $\p... | g35502 | [
0.02700517326593399,
-0.015141329728066921,
0.01682940125465393,
0.009786782786250114,
-0.031280383467674255,
-0.013768961653113365,
0.042603954672813416,
0.024521147832274437,
-0.05541389063000679,
0.013703780248761177,
-0.04093540832400322,
0.010885855183005333,
0.06764275580644608,
0.04... |
<p>I am using a random forest code to run one random forest model and distinguish which variables are important for classification and then to run a second random forest model using only these variables to reduce noise. The problem is that different variables are added to the model on different iterations of this proce... | g25786 | [
-0.0014507102314382792,
-0.09077085554599762,
0.026337511837482452,
-0.04811493679881096,
0.03387052193284035,
-0.019355351105332375,
-0.052524060010910034,
-0.005971367005258799,
-0.03170612081885338,
0.017427191138267517,
-0.015559643507003784,
-0.016176417469978333,
-0.028996160253882408,... |
<p>Given the following Bayes network:</p>
<p><img src="http://i.stack.imgur.com/O7H7b.png" alt="BayesNet"></p>
<p>with </p>
<ul>
<li>$p(k=t)=.2$</li>
<li>$p(o=t)=.1$</li>
<li>$p(s=t|k=f,o=f)=.0$</li>
<li>$p(s=t|k=f,o=t)=.2$</li>
<li>$p(s=t|k=t,o=f)=.5$</li>
<li>$p(s=t|k=t,o=t)=.95$</li>
</ul>
<p>how would I calcula... | g66664 | [
0.02743002213537693,
0.0724872350692749,
-0.01800783909857273,
-0.006086387671530247,
0.01637871563434601,
-0.061105936765670776,
-0.028294142335653305,
0.03076116554439068,
-0.03983687236905098,
-0.011507741175591946,
-0.051321957260370255,
0.026724444702267647,
0.0847582221031189,
0.0065... |
<p>I’m performing a meta-analysis in which the main outcome of interest is a correlation coefficient between two variables, $X$ (a psychological measure) and $Y$ (a biomarker). $Y$ is known to be strongly correlated with covariate $Z$ (age).</p>
<p>I originally intended to do an individual patient data meta-analysis (... | g66665 | [
-0.004074399825185537,
0.003466659225523472,
0.0023316331207752228,
-0.0603291355073452,
-0.007099172566086054,
-0.006923425942659378,
0.009563556872308254,
-0.016648540273308754,
0.014155280776321888,
-0.05516371130943298,
0.04154558107256889,
-0.01947476714849472,
0.028801802545785904,
0... |
<p>How do you calculate the odds of winning one of 10 prizes if you have $t$ tickets entered in a drawing with $T$ total tickets? Each person can only get one prize. A person with 20 tickets entered obviously has higher odds than someone with 1 ticket. There are 50 people with tickets in the jar. </p>
<p>So if I had 2... | g25788 | [
0.03252819553017616,
0.007134768180549145,
0.038287267088890076,
-0.011714276857674122,
-0.010615294799208641,
-0.06918586790561676,
0.04182649776339531,
0.02608419395983219,
-0.0003306852886453271,
0.004200359340757132,
0.0009694270556792617,
-0.04965423420071602,
0.0023106716107577085,
0... |
<p>I am looking for a classification algorithm that emits probabilities for each label and supports real-valued features.</p>
<p>1) From what I gather, logistic regression may output a variable in $(0, 1)$, however, it does not describe the true classification probability.</p>
<p>2) Naive Bayes supports probabilities... | g66666 | [
0.012142802588641644,
-0.04429739713668823,
0.0025868157390505075,
-0.02640659175813198,
-0.0323481559753418,
-0.03716833516955376,
-0.037096381187438965,
0.038021236658096313,
-0.06669284403324127,
-0.0314672626554966,
0.04736429452896118,
0.03566548973321915,
0.07796028256416321,
0.04895... |
<p>Suppose we have some data points that we believe they follow $N(\mu, \sigma^2)$, and both parameters are unknown . I want to assign conjugate prior distributions on both $\mu$ and $\sigma^2$, and then obtain the posterior distribution. How this can be done in R?</p> | g46155 | [
0.06149011477828026,
-0.09555266797542572,
-0.015700867399573326,
-0.048445023596286774,
-0.039059024304151535,
-0.031895119696855545,
-0.006231342442333698,
0.011363556608557701,
-0.027260977774858475,
0.0007429050165228546,
-0.01182752288877964,
0.03797387331724167,
-0.00827878713607788,
... |
<p>I am trying to understand a) what relative validity is, and b) how to test it statistically. So far I have gathered, from sources such as <a href="http://www.psychology.uiowa.edu/faculty/wasserman/glossary/relative%20validity.html" rel="nofollow">this</a> that relative validity is a larger reliability in causation a... | g66667 | [
-0.004801456350833178,
0.021059541031718254,
-0.006769389379769564,
-0.012265107594430447,
-0.0156386811286211,
-0.0012305297423154116,
0.04218557849526405,
0.04868499934673309,
-0.009548901580274105,
-0.033407408744096756,
0.014008121564984322,
0.027465861290693283,
0.08564979583024979,
0... |
<p>If I go to <a href="https://www.coursera.org/course/neuralnets" rel="nofollow">https://www.coursera.org/course/neuralnets</a></p>
<p>and click preview, there are many video lectures. Does anyone know if these are the same lectures you see if you enroll in a course?</p> | g46158 | [
-0.014054963365197182,
0.05398331582546234,
0.004112930037081242,
-0.000335373159032315,
0.01797889918088913,
-0.02234819531440735,
0.028674008324742317,
0.005970281548798084,
0.022335415706038475,
-0.027888553217053413,
0.013914467766880989,
0.025119978934526443,
0.06555430591106415,
0.07... |
<p>I have estimated the parameters of normal distribution with GMM
and got the follwing results :</p>
<p>mean = -0.01168 , p-value = 0.83519</p>
<p>i'm bit confused in interpreting the result. can i say that the mean is zero as it is not statistically significant. </p>
<p>thanks </p> | g66668 | [
-0.005957564804702997,
0.0073977261781692505,
-0.010664569213986397,
0.015248765237629414,
0.024192117154598236,
0.047278206795454025,
0.014276610687375069,
-0.012296561151742935,
-0.031238900497555733,
-0.0322980098426342,
-0.017931850627064705,
-0.00503257941454649,
0.01272006519138813,
... |
<p>Zuur (2013) 'Beginners Guide to GLM and GLMM' states that if the Pearson residuals, when plotted against fitted values from a poisson regression, show the pattern below then the assumption of poisson distributed observations is violated. Zuur urges to try a negative binomial regression if the residuals show a patter... | g5074 | [
0.05235765874385834,
-0.052795443683862686,
-0.021738750860095024,
-0.01665855199098587,
-0.0197613425552845,
0.03886495903134346,
0.002200074726715684,
0.010870632715523243,
-0.09849979728460312,
-0.04961441457271576,
0.04675886780023575,
-0.017972001805901527,
-0.003277525771409273,
-0.0... |
<p>I have run a multinomial logistic regression test for the interaction between species of deer, days a camera trap was in the field and type of reaction.</p>
<p>The model with the best AIC value was:</p>
<pre><code>Coefficients:
(Intercept) speciesmuntjac speciesroe speciessika days
r -0.7471023 ... | g17177 | [
-0.008208530023694038,
-0.06369849294424057,
-0.0072173140943050385,
0.0015438477275893092,
-0.01265313383191824,
-0.07387370616197586,
0.05124419555068016,
0.02286061830818653,
0.015161393210291862,
-0.026231762021780014,
-0.05264468863606453,
0.020457271486520767,
0.04955645650625229,
-0... |
<p>What is the difference between statistical significance (based on probability) and an effect size?</p>
<p>I am fairly new to stats and finding a bit of an up hill marathon at the moment. I have been asked to research the question posted above, yet I have exhausted my resources and I am still non the wiser on how to... | g66669 | [
0.032533660531044006,
0.028897620737552643,
0.01192872878164053,
-0.018410202115774155,
-0.014656534418463707,
0.03781125321984291,
0.05978510156273842,
0.027908766642212868,
-0.012314943596720695,
-0.05726394057273865,
0.015602807514369488,
0.007380138151347637,
0.0316377654671669,
0.0076... |
<p>Given $X_t$ a multivariate random gaussian variable of covariance matrix $N_{tt'}$ diagonal in Fourier space (sampling is equally spaced),</p>
<p>I would like to parametrise its power spectrum as:
$S_X(f) = \frac{a}{f^\alpha} + b$, for $f\in[f_{min},f_{max}]$
and estimate $a$, $b$ and $\alpha$.</p>
<p>Any idea how... | g66670 | [
-0.0012738712830469012,
-0.07210157811641693,
-0.033248405903577805,
-0.06354356557130814,
0.0008978051482699811,
-0.030294639989733696,
-0.056793857365846634,
-0.011347854509949684,
-0.04407085105776787,
0.00024029014457482845,
0.011794110760092735,
-0.03355606645345688,
0.00158895878121256... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.