question stringlengths 37 38.8k | group_id stringlengths 2 6 | sentence_embeddings listlengths 768 768 |
|---|---|---|
<p>I need to implement a program that will classify records into 2 categories (true/false) based on some training data, and I was wondering at which algorithm/methodology I should be looking at. There seem to be a lot of them to choose from -- Artificial Neural Network, Genetic Algorithm, Machine Learning, Bayesian Opt... | g23602 | [
0.040176741778850555,
-0.022531185299158096,
-0.017537306994199753,
-0.029479561373591423,
0.004440377466380596,
-0.032603006809949875,
0.038922905921936035,
0.05636812746524811,
-0.06844159960746765,
-0.017565572634339333,
-0.0015635921154171228,
0.07651051878929138,
0.10356102883815765,
... |
<p>I am working in hospital processing infection data, and start to read more and more articles on regressions and statistics, having realized that my mathematics background is not sufficient for me to handle all the maths inside the article. I plan to do some self-study.</p>
<p>I have seen from <a href="http://www.bi... | g38207 | [
0.08394016325473785,
0.00784699060022831,
-0.0021954053081572056,
-0.013124486431479454,
-0.014805080369114876,
-0.030560161918401718,
0.024539213627576828,
-0.017411790788173676,
-0.014028779231011868,
0.0025742279831320047,
0.012666776776313782,
0.06122122332453728,
0.06682617962360382,
... |
<p>I am working on something to test advertisements. I have 3 independent variables I want to test (with mixed numbers of variations of each variable), and I would like to find the best combination of the three by looking at their effect on a single dependent variable (the percentage who purchase).</p>
<pre><code>TIT... | g65144 | [
0.007583231199532747,
0.004548874218016863,
0.0010267652105540037,
-0.02325817011296749,
-0.00016734999371692538,
-0.03929378092288971,
0.01636507920920849,
0.015626227483153343,
-0.034077685326337814,
-0.020648010075092316,
-0.019058769568800926,
0.009762674570083618,
-0.011323250830173492,... |
<p>I want to look a the effect of an intervention on work satisfaction and motivation. The data not normally distributed. I have two groups, intervention and control, with 11 in each group. I measure pre- and post-intervention using scales.</p>
<p>I want to test the effectiveness of this intervention.</p>
<p>I suspec... | g65145 | [
-0.0010100200306624174,
0.022249674424529076,
-0.02297011949121952,
-0.060285814106464386,
0.007630304899066687,
0.0023308193776756525,
0.020059270784258842,
0.00851054023951292,
-0.030464187264442444,
-0.009384683333337307,
0.03190133720636368,
0.009857996366918087,
-0.03304288163781166,
... |
<p>The Spearman’s rank correlation coefficient calculated for these observations is 0.826 (p<0.005). Is there something like a "rule of thumb" minimum number of observations?</p> | g27054 | [
-0.011551686562597752,
-0.012273771688342094,
-0.007846733555197716,
-0.060879915952682495,
0.03938193619251251,
0.013303753919899464,
0.06346208602190018,
-0.01543390192091465,
0.004639067221432924,
-0.028754359111189842,
0.01009738352149725,
0.040019914507865906,
0.047589097172021866,
0.... |
<p>I have some points $X=\{x_1,...,x_n\}$ in $R^p$, and I want to cluster the points so that:</p>
<ol>
<li><p>Each cluster contains an equal number of elements of $X$. (Assume that the number of clusters divides $n$.)</p></li>
<li><p>Each cluster is "spatially cohesive" in some sense, like the clusters from $k$-means.... | g49637 | [
0.026858076453208923,
0.01512504369020462,
-0.013140362687408924,
-0.05168317258358002,
0.07712770253419876,
-0.05169972404837608,
-0.04998723790049553,
0.01415275502949953,
-0.00680901762098074,
0.02727346494793892,
-0.005516496486961842,
0.010581652633845806,
0.06390826404094696,
0.01061... |
<p>There is a bayesian network Asia:</p>
<p><img src="http://i.stack.imgur.com/sCh2D.png" alt="enter image description here"></p>
<p>I am computing based on</p>
<pre><code>A (visit to Asia)
S (smoker)
T (tuberculosis)
L (lung cancer)
B (bronchitis)
E (tuberculosis versus lung cancer/bronchitis)
D (dyspnoea)
X (chest... | g65146 | [
0.015175625681877136,
-0.03778470307588577,
0.001428939402103424,
-0.03429904207587242,
0.025779882445931435,
-0.0011434629559516907,
0.004077160730957985,
0.025520024821162224,
-0.048432134091854095,
-0.03212793916463852,
-0.006558924447745085,
0.020965347066521645,
0.08780501782894135,
0... |
<p>I'm looking at the influence of pollen type on whether a flower sets fruit (i.e., yes or no = 1 or 0). Then looking at number of seeds per fruit (1-6 possible).</p>
<p>I was told I should use lmer, however it gave me an error: </p>
<blockquote>
<p>calling lmer with 'family' is deprecated; please use glmer() ins... | g65147 | [
0.008330486714839935,
0.0335380919277668,
0.008867211639881134,
-0.0679452046751976,
-0.015793778002262115,
-0.05577436462044716,
-0.003280898090451956,
-0.00790464784950018,
-0.03492027521133423,
-0.03774043917655945,
-0.013271587900817394,
-0.022291293367743492,
0.04793599247932434,
-0.0... |
<p>I am working with a NIR matrix consistent of 134 rows (samples) and 1529 columns (wavelengths), from which I want to discriminate between two categories (species).
I have successfully used the plsda model from "caret" library, but when I want to predict new samples I only get either category A or B, and I need to kn... | g23610 | [
-0.01171960961073637,
-0.08095011860132217,
0.013356080278754234,
-0.0442626029253006,
0.02262287773191929,
-0.03138624504208565,
0.023509806022047997,
0.0022506630048155785,
-0.04616018757224083,
-0.020560409873723984,
0.023566652089357376,
0.03490438312292099,
0.017799165099859238,
-0.00... |
<p>The definition for completeness is that if a statistic $s(x)$ is complete, we have that for every measurable $g$,
$$E_\theta(g(s(x))) = 0\,, \ \forall\,\theta\ \Rightarrow\ g(s) = 0 \text{ a.s.}$$</p>
<p>I've heard that we can think of completeness as saying that if we wanted to estimate the zero function using a ... | g23612 | [
0.06347855180501938,
0.01259559951722622,
0.012184573337435722,
0.04309527948498726,
0.04753316938877106,
-0.01129637286067009,
0.033694036304950714,
0.04161684960126877,
-0.03312837705016136,
-0.015412909910082817,
-0.033405039459466934,
-0.027173912152647972,
0.020506661385297775,
0.0112... |
<p>I've been told by my stats prof that running an ANCOVA relies on a series of assumptions, including that the the dependent variable and the covariate are linearly related. So, in SPSS the first thing to do before running ANCOVA is to check for bivariate correlation between them.</p>
<p>The question is, if that corr... | g65148 | [
0.01653517596423626,
-0.01387098990380764,
0.008626757189631462,
-0.033018577843904495,
-0.04055938124656677,
0.019838586449623108,
0.0364445336163044,
0.009369969367980957,
-0.027417408302426338,
-0.04167938232421875,
0.0057772439904510975,
0.017718756571412086,
0.025738965719938278,
0.02... |
<p>I have kinetic data measured under several treatments (one experiment per treatment) which can be fitted by several nonlinear two-parameter models, how can I compare whether there there are differences in response that vary by treatment?</p>
<p><strong>Comparing model fits.</strong> My initial thought was to use an... | g65149 | [
0.010634212754666805,
-0.07364074140787125,
-0.019230712205171585,
-0.012643398717045784,
-0.0017592022195458412,
-0.06699622422456741,
0.0474887453019619,
-0.00888280849903822,
-0.02250107191503048,
0.015374771319329739,
0.008027867414057255,
0.01247322652488947,
0.025666644796729088,
-0.... |
<p>This page describes briefly on micro and macro precision used in computational evaluation: <a href="http://rushdishams.blogspot.de/2011/08/micro-and-macro-average-of-precision.html" rel="nofollow">http://rushdishams.blogspot.de/2011/08/micro-and-macro-average-of-precision.html</a></p>
<p>This paper surveys the eval... | g65150 | [
-0.049707576632499695,
-0.06045322120189667,
0.020108377560973167,
-0.005959032569080591,
-0.002073545940220356,
-0.054622337222099304,
0.013766804710030556,
0.04791547358036041,
-0.04413190856575966,
-0.005336487200111151,
0.0004430349508766085,
-0.0035028508864343166,
0.015090761706233025,... |
<p>I have constant time series (yearly from 1950 to 2010) of the abundance of several species that were captured by different groups. These series are somewhat related because the quantity of all species captured is dependent on the same effort (which is not always the same each year, but evolves differently per group)... | g26253 | [
-0.027725962921977043,
-0.06529422104358673,
-0.009587901644408703,
-0.04361872375011444,
-0.020006975159049034,
0.0020847024861723185,
0.021025819703936577,
-0.004697057418525219,
-0.048670023679733276,
0.04067056253552437,
-0.004458700306713581,
0.034101590514183044,
0.024431202560663223,
... |
<p>As I read in Bishop's PRML (here is the clip of that part about FA):</p>
<p><img src="http://i.stack.imgur.com/6qBlj.png" alt="enter image description here"></p>
<p>According to the highlighted part, factor analysis <em>captures the covariance between variables in the matrix $W$</em>. I wonder <strong>HOW</strong>... | g65151 | [
0.016096331179142,
-0.029182426631450653,
-0.005028014536947012,
-0.049522656947374344,
0.04867852106690407,
-0.0045234872959554195,
0.05461835116147995,
0.01061964686959982,
-0.04387401044368744,
-0.0038984816055744886,
-0.034812889993190765,
0.027624012902379036,
0.022199595347046852,
-0... |
<p>I am designing new functionality in a web application, and I am testing two variations on the navigation to attempt to determine which approach is more successful for our users. I am running the test using a remote testing tool called <a href="http://solidifyapp.com" rel="nofollow">Solidify</a>.</p>
<p>For each var... | g23618 | [
-0.040826234966516495,
-0.000324178283335641,
-0.023081619292497635,
0.019777586683630943,
-0.014358783140778542,
0.008081081323325634,
0.05059673264622688,
-0.014748864807188511,
-0.0191439688205719,
-0.02752630226314068,
0.04666239023208618,
-0.02204901911318302,
0.041776590049266815,
0.... |
<p>Can you please help me figuring out what the covariance structure of a model with random intercept and random slope is?</p>
<p>Here is my model $Y_{ij} = \beta_0 + \beta_1 t_{ij} + b_{0,i} + b_{1,i}t_{ij} + e_{ij}$ </p>
<p>where $b_{0,i}$ and $b_{1,i}$ are random intercept and random slope and we know that $e_{ij}... | g65152 | [
-0.014012654311954975,
-0.033035408705472946,
-0.006219351664185524,
0.014562144875526428,
0.03649991750717163,
-0.0029485432896763086,
0.06785915046930313,
0.027045294642448425,
-0.002182349096983671,
0.012091940268874168,
-0.0042309751734137535,
0.029669715091586113,
-0.045566000044345856,... |
<p>I ran OLS regression in Stata.
Based <strong>only</strong> on the results I got in OLS, is there any way to know if the quantile regression will be a better choice?</p> | g29076 | [
-0.024850942194461823,
-0.06036290526390076,
0.005176464095711708,
-0.02861664816737175,
0.00652902340516448,
-0.03193863481283188,
0.021959979087114334,
-0.01802857220172882,
0.04714995250105858,
-0.06557644158601761,
0.031314101070165634,
0.019887957721948624,
0.08764804899692535,
0.0014... |
<p>Hey, im a beginner to R and trying to run pvclust so as to test a cluster solution.</p>
<p>I've managed to load data and run the heirachical cluster, however the code i find online for running pvclust is constantly producing errors - just wondering if someone can point out where I'm going wrong...</p>
<p>here is m... | g43515 | [
-0.006256341002881527,
-0.032882802188396454,
0.020173776894807816,
-0.07529014348983765,
0.04357710853219032,
-0.028153281658887863,
0.021134858950972557,
-0.059490788727998734,
-0.026553640142083168,
-0.0167763140052557,
-0.0002373723400523886,
0.029344012960791588,
0.05217111110687256,
... |
<p>I'm reviewing a paper whereby the nonhomogeneous poisson process is explored. I'm familiar with the intensity function, but the idea of the hazard function is throwing me off. Especially, I cannot figure out when they two are the same? Literature is sparse and I'm just becoming confused. To me, it seems like the int... | g65153 | [
0.009281271137297153,
-0.01873021200299263,
-0.004549345467239618,
-0.02969418652355671,
0.01815793663263321,
-0.004733420442789793,
0.017381878569722176,
-0.023022020235657692,
-0.07086293399333954,
-0.007070797495543957,
-0.0405208095908165,
0.01848950982093811,
0.02813277766108513,
-0.0... |
<p>I am trying to classify a question type, as a "Type" . It can be classified into 6 types.
I am using an ARFF file as input to weka with 99 training entries. I have got a model in place, and it has an accuracy of 85% (obtained using cross validation), which is to my satisfaction.</p>
<p>Now, when I want to test thi... | g23633 | [
0.039880625903606415,
-0.015866385772824287,
0.018232157453894615,
-0.10541176050901413,
0.07924246788024902,
0.01301510725170374,
0.08253707736730576,
0.017286302521824837,
-0.0445486381649971,
-0.029466304928064346,
-0.0007731948862783611,
0.020647460594773293,
0.0540628619492054,
0.0155... |
<p>I'm trying to understand how fitted values are calculated for ARMA(p,q) models. I've already found a question on here concerning fitted values of ARMA processes but haven't been able to make sense of it. </p>
<p>If I have a ARMA(1,1) model, i. e. </p>
<p>$$X_t = \alpha_1X_{t-1}+\epsilon_t - \beta_1 \epsilon_{t-1}$... | g65154 | [
0.028124431148171425,
-0.04347988963127136,
-0.01059174258261919,
-0.001157537684775889,
0.01725064218044281,
0.01720082201063633,
0.0013570105656981468,
0.020472388714551926,
-0.018365226686000824,
0.055552832782268524,
-0.04515225067734718,
0.047595057636499405,
0.06919214129447937,
0.02... |
<p>I'm trying to use the EM cluster algorithm, provided by the software Weka, to classify my data and it only finds one cluster. </p>
<ul>
<li>Could I interpret this as there are no ways to distinguish the instances in my sample? </li>
</ul>
<p>This is a result that is coherent with others analysis that I'm doing to... | g901 | [
-0.0021830720361322165,
-0.04354342073202133,
-0.005197789985686541,
-0.053850989788770676,
0.01946811005473137,
-0.03195234388113022,
0.014878232032060623,
0.04873741418123245,
-0.00944592896848917,
-0.03289082273840904,
0.03414450213313103,
0.009652365930378437,
0.07130003720521927,
0.02... |
<p>I have performed a Cochran's Q test for a within-subjects experimental design with 3 conditions and 36 participants with a dichotomous dependent variable.</p>
<p>I found a (just) statistically significant effect ($\chi^2$ = 6.00, df = 2, p = 0.04979) and would like to also report the effect size, but haven't been a... | g65155 | [
-0.02391473390161991,
0.020426500588655472,
-0.024098729714751244,
-0.06386744976043701,
-0.02583603747189045,
-0.03299431502819061,
0.02318337745964527,
0.0399622842669487,
-0.0522351935505867,
-0.03171396255493164,
-0.007162719964981079,
-0.00813037808984518,
0.043734095990657806,
0.0288... |
<p>Suppose I thought that ingesting greater than 100 mg of chemical X annually noticeably decreased one's weight. Also, I had data (from a "natural" experiment) from 100 people (some male and some female) measuring how much of chemical X they had eaten, and their weights at the time of the experiment. </p>
<ul>
<li>Wh... | g65156 | [
0.05004725977778435,
0.021440956741571426,
0.015309262089431286,
-0.02756928652524948,
0.021099748089909554,
-0.031094003468751907,
-0.05104536935687065,
0.017544498667120934,
-0.026699699461460114,
-0.06656289100646973,
-0.005634997505694628,
0.027493944391608238,
0.053640127182006836,
0.... |
<p>I participate in predictive modeling competitions on <a href="http://www.kaggle.com/">Kaggle</a>, <a href="http://tunedit.org/">TunedIt</a>, and <a href="http://www.crowdanalytix.com/">CrowdAnalytix</a>. I find that these sites are a good way to "work-out" for statistics/machine learning. </p>
<ul>
<li>Are there a... | g49411 | [
-0.02866300567984581,
0.013953638263046741,
0.02037249691784382,
0.0010469701373949647,
0.027843380346894264,
-0.04373401775956154,
0.018684327602386475,
0.04155611991882324,
0.001407425501383841,
-0.03102024830877781,
0.022787706926465034,
-0.007937523536384106,
0.06242789700627327,
0.020... |
<p>I'm trying to forecast hourly data for 30 days for a process.</p>
<p>I have used the following code:</p>
<pre><code>#The packages required for projection are loaded
library("forecast")
library("zoo")
</code></pre>
<h3>Data Preparation steps</h3>
<p>There is an assumption that we have all the data for all the 24 ... | g4717 | [
-0.013708735816180706,
0.00807865895330906,
-0.018054116517305374,
-0.05935857072472572,
0.004759167321026325,
-0.008343320339918137,
-0.017029233276844025,
-0.011981592513620853,
-0.04163128137588501,
-0.032486218959093094,
0.00812828354537487,
-0.028687376528978348,
0.06369441747665405,
... |
<p>I know I'm asking a lot of questions these days! Sorry about that, but I'm trying to work through my grad thesis data collected over the last 4 years, and am repeatedly tripping on my beginner's grasp on stats.</p>
<p><strong>The background:</strong>
My basic question is the same as described in <a href="http://sta... | g65157 | [
-0.02606009505689144,
-0.030032929033041,
-0.016760028898715973,
-0.028175482526421547,
-0.05566675588488579,
-0.009961503557860851,
-0.0022408701479434967,
-0.011624044738709927,
-0.020505912601947784,
-0.006346000358462334,
0.004892008379101753,
0.022491926327347755,
0.04455932229757309,
... |
<p>Let's say we have data of the following form: a categorical response $y$ and covariates $x_1,x_2,...,x_p$ that can be either categorical or continuous (a very common scenario). Further, let's say the covariates are noisy, and there are a lot of them (high dimensionality).</p>
<p>What machine learning / R-packages a... | g4718 | [
0.02823636867105961,
-0.027314582839608192,
-0.000416046503232792,
-0.026090266183018684,
-0.009425099939107895,
-0.03871513530611992,
0.006348663941025734,
0.02639879658818245,
-0.034049272537231445,
0.006102416198700666,
0.02487625740468502,
-0.021336492151021957,
0.07459505647420883,
0.... |
<p>Is the method of mean substitution for replacing missing data out of date? Are there more sophisticated models that should be used? If so, what are they?</p> | g23641 | [
0.005581366363912821,
-0.047250375151634216,
0.004445947706699371,
-0.04523685202002525,
0.003667083103209734,
0.025142107158899307,
-0.0036246750969439745,
-0.019058693200349808,
-0.03128853812813759,
-0.007630891632288694,
-0.002120437566190958,
-0.06370708346366882,
0.05437252297997475,
... |
<p>I'm having trouble understanding the formal definition of a confidence set. This is the definition that I am working under.</p>
<p><strong>Definition (Confidence Set):</strong> Let the data be distributed according to the random variable $X$, which depends on a parameter $\theta$ taken from a parameter space $\Thet... | g23642 | [
0.014833311550319195,
0.017989713698625565,
-0.022111576050519943,
0.0021252240985631943,
0.029786506667733192,
0.06279554963111877,
0.018718846142292023,
0.0037807764019817114,
-0.07822007685899734,
-0.06804187595844269,
0.0019183174008503556,
0.009577537886798382,
-0.050613611936569214,
... |
<p>Let us consider a ordinal variable with four values say A,B,C,D (A greater than B greater than C greater than D) and a person can have any of these values at a given point in time. I have data which has a timestamp and the state in which the person was present. I would like to quantify the shift between these catego... | g65158 | [
0.025984598323702812,
-0.06391005218029022,
-0.03674837201833725,
-0.07343936711549759,
0.040388088673353195,
-0.015132589265704155,
0.022192465141415596,
-0.01205725222826004,
-0.05280786007642746,
0.034490134567022324,
-0.0009728345321491361,
0.010614316910505295,
0.006613968871533871,
0... |
<p>This is a bit longish (I want to be thorough), but my actual question is a short one (in bold below).</p>
<p><strong>BACKGROUND:</strong> Suppose I have a conditional <strong>logistic discrete time event history model</strong> (aka logistic discrete time survival models aka logit hazard model) across $p$ possibly t... | g65159 | [
0.012948872521519661,
-0.03316901996731758,
0.011331746354699135,
-0.025526262819767,
-0.005236409604549408,
0.006205140147358179,
0.02417559176683426,
-0.013195696286857128,
-0.025503728538751602,
-0.05013088881969452,
-0.004139336291700602,
0.029076693579554558,
0.06031309440732002,
0.01... |
<ol>
<li><p>The definition of complete statistics is from
<a href="http://en.wikipedia.org/wiki/Completeness_(statistics)#Definition" rel="nofollow">http://en.wikipedia.org/wiki/Completeness_(statistics)#Definition</a></p>
<blockquote>
<p>The statistic $s$ is said to be complete for the distribution of $X$ if
for ... | g65160 | [
0.007185574155300856,
-0.005760726053267717,
0.005903401877731085,
0.0051170275546610355,
-0.04176437109708786,
-0.05372833460569382,
0.052416812628507614,
-0.015652569010853767,
-0.025824880227446556,
-0.04009292274713516,
-0.05444620922207832,
0.00301299337297678,
0.023636596277356148,
-... |
<p>I'm trying to model time series data that is bimodal and non-Gaussian. The 2 modes are due to weekday points versus weekend points. I keep thinking that I just need to split the data up to model weekdays separately from weekends but then there are breaks in the time series (i.e. I loose very obvious inter-day trends... | g65161 | [
-0.027586419135332108,
-0.02477411739528179,
-0.00359823415055871,
-0.0602881945669651,
-0.0074005997739732265,
-0.014487716369330883,
0.03549369424581528,
0.008803294971585274,
-0.021133700385689735,
0.0007308948552235961,
0.00786564126610756,
-0.04770828038454056,
0.056850843131542206,
-... |
<p>I found many tests like: Fligner, Levene etc etc to check homogeneity of variances, my question is: What is the difference between those tests and ANOVA ?</p>
<p>Thank you</p> | g46447 | [
0.059134893119335175,
-0.01584368385374546,
-0.008393733762204647,
0.013650734908878803,
0.0242950189858675,
0.003777017118409276,
0.03353921324014664,
-0.01208461169153452,
-0.0012999604223296046,
-0.041574232280254364,
-0.014216265641152859,
0.04722290858626366,
-0.0031531518325209618,
0... |
<p>Suppose that we want to test the hypothesis that the proportion of blue-eyed martians has been decreasing throughout the 20th century. Unfortunately, the Martian population fluctuates highly, so every decade there is large difference in the total population [update: consider the Martian population to be constant at ... | g19545 | [
0.02053043432533741,
0.024519719183444977,
0.012343987822532654,
-0.05336964130401611,
0.024716177955269814,
0.032537780702114105,
0.03301418572664261,
0.0015779680106788874,
0.010786277242004871,
-0.01378388050943613,
0.05274461582303047,
0.039676010608673096,
0.04085194319486618,
0.07419... |
<p>I have four datasets: morphological measurements for a set of species (M1), ecological measurements for the same set of species (E1), morphological measurements for a second set of species (M2), and ecological measurements for this second set of species (E2). </p>
<p>I am interested in finding the linear combinatio... | g65162 | [
0.034911155700683594,
-0.05117744952440262,
-0.003620533738285303,
-0.012455077841877937,
-0.015019480139017105,
-0.09201642870903015,
0.0638979971408844,
-0.027552731335163116,
-0.035203877836465836,
0.004795226734131575,
0.008382530882954597,
-0.00012661839718930423,
0.05087250471115112,
... |
<p>I have N variables in K samples. There is a classification variable, T (treatment), and a confounding variable -- sex. Unfortunately, in the "no treatment" (CTRL) group there are significantly more females than in the "treatment" (TRT) group:</p>
<pre><code> TRT CTRL
Male 40 15
Female 22 ... | g35148 | [
0.002802880248054862,
-0.09437782317399979,
0.002756641013547778,
-0.06598968058824539,
-0.016440922394394875,
-0.026828842237591743,
-0.028340106830000877,
0.003345784032717347,
-0.04236219450831413,
0.04818045347929001,
0.03991143777966499,
0.028717638924717903,
0.03593318164348602,
0.05... |
<p>I would like to fit a Weibull to a set of data. However, I dont have the survival time of each data, but the total number. That means: I know that after 10 months 0.85 ($n=500$) survived, after 20 months 0.65,... and after 60 months 0.40 (7 pairs).
I have these information for two groups: first group products with s... | g65163 | [
0.019433841109275818,
-0.05443676933646202,
0.011385897174477577,
-0.014043532311916351,
-0.021249966695904732,
-0.021452220156788826,
0.011815845035016537,
-0.03581347316503525,
-0.05742970481514931,
0.009901939891278744,
-0.0308437068015337,
0.008558939211070538,
0.05985254421830177,
0.0... |
<p>I'm trying to develop a score for biomarker discovery in two-class high throughput biological data. At this stage the significance of the score (p-value) is estimated by permutation of the class labels, but now I'm asked to study its variance in order to assign p-values in more rigorous terms. I've understood that I... | g4 | [
0.0021883295848965645,
0.009191125631332397,
-0.03693361207842827,
-0.059928957372903824,
0.026005154475569725,
-0.010745856910943985,
0.030854932963848114,
0.0012975024292245507,
-0.061004407703876495,
-0.01802693121135235,
-0.004946560133248568,
0.04410067945718765,
0.038288600742816925,
... |
<p>What I have is a medical data set with several variables, all 0-1 variables. I want to make inference about them with logistic regression. I have a few problems:</p>
<ol>
<li><p>I have location variables for the disease. I was advised by my statistic advisor to put them in bins as follows: If it was solely in the r... | g65164 | [
0.02001112885773182,
-0.033480800688266754,
0.0036921913269907236,
-0.012304103933274746,
0.03550275042653084,
-0.03701333701610565,
0.017258867621421814,
-0.0033595841377973557,
-0.08109010010957718,
-0.033580515533685684,
0.045464225113391876,
0.02250644378364086,
0.025255220010876656,
0... |
<p>Please, could anyone give an example of a stationary time series? I mean, if for instance $x_{1}$, $x_{2}$, $x_{3}$, $x_{4}$, $x_{5}$ are the 5 first random variables of the series, what would be the joint distribution of ($x_{1}$, $x_{2}$,$x_{3}$, $x_{4}$, $x_{5}$)? And then what would be the joint distribution of ... | g65165 | [
0.03277566656470299,
0.021546533331274986,
-0.013968345709145069,
-0.026874471455812454,
-0.019218502566218376,
-0.034491099417209625,
0.024110455065965652,
-0.05450175330042839,
-0.04609882831573486,
0.017854487523436546,
-0.03156619146466255,
0.01879938691854477,
-0.03048104979097843,
-0... |
<p>I am running a post-hoc analysis on the data collected during an experiment in which 15 unique stimuli were presented to participants. Having run a least squares regression using the lm() function in R I have found significant results for a subset of the data including 90 observations from 6 participants with two co... | g23655 | [
-0.006177819799631834,
-0.04848429560661316,
0.006799438968300819,
-0.024568527936935425,
0.003699175314977765,
-0.01726788654923439,
0.04209655895829201,
0.027105005457997322,
-0.00501693831756711,
-0.03328828886151314,
0.014161400496959686,
0.020123282447457314,
0.005942998453974724,
0.0... |
<p>As the title says I want to quantify the difference in the rates of sequence change between genes. When I measure the mutation rates between my subgenomes I can determine a significant but slight difference via wilcoxon test (the distributions are gaussian but with tails). This ends up being true for many of the dif... | g65166 | [
0.006533509120345116,
-0.03210006654262543,
-0.0006474413094110787,
-0.036349955946207047,
0.038181040436029434,
-0.05108407884836197,
0.003392808837816119,
0.05601824074983597,
-0.007441709749400616,
0.010290265083312988,
0.02163066156208515,
0.028925590217113495,
0.029568398371338844,
0.... |
<p>Why is it important to understand random sampling when drawing a conclusion about a population from a sample and what are the examples of business environment where the concept of business environment is important</p> | g65167 | [
0.0065874336287379265,
0.06257935613393784,
0.018208926543593407,
-0.004350532311946154,
-0.034165751188993454,
0.0406574048101902,
0.011181218549609184,
-0.031233562156558037,
0.0012894519604742527,
-0.025521570816636086,
0.02938040718436241,
0.009823370724916458,
-0.002606794936582446,
0... |
<p>I know there are some other questions out there on book recommendations, but I've looked into a lot of the books in those answers and haven't quite found what I'm looking for.</p>
<p>I am going to be starting a Masters program in Predictive Analytics this fall. My background is Bachelor's in CS with a couple years... | g65168 | [
0.06945832818746567,
0.014203243888914585,
0.027629366144537926,
-0.005140732042491436,
-0.038342516869306564,
0.016039153560996056,
0.05541754141449928,
-0.016283689066767693,
-0.0019478979520499706,
-0.025899343192577362,
0.016171947121620178,
0.02099592611193657,
0.06968424469232559,
-0... |
<p>My question is about the use of an offset in a mixed GAM. This question is kind of a follow-up to this post <a href="http://stats.stackexchange.com/questions/104113/probability-distribution-for-right-skewed-data">Probability distribution for right skewed data</a>. </p>
<p>I was looking to test the relationship betw... | g65169 | [
0.02703423984348774,
-0.07522176206111908,
-0.002029131632298231,
-0.04279274120926857,
-0.04403463378548622,
0.05862848088145256,
0.06450581550598145,
0.042445771396160126,
0.030518079176545143,
0.022120948880910873,
0.03159460425376892,
0.016790203750133514,
0.0035250578075647354,
0.0010... |
<p>In the scenario in which I'm working each entity could be represented in terms of ten distinct properties that I will call p1, p2, ..., pn.
For each of them, an entity, can have its specific range of values for a single property.
An entity's property couldn't have any value associated to it.</p>
<p>Formally speakin... | g23657 | [
-0.00040690001333132386,
0.009995874017477036,
-0.0007474618032574654,
-0.05254414677619934,
0.010608945041894913,
-0.04428405314683914,
-0.05960182845592499,
0.08067790418863297,
-0.04415078088641167,
-0.0036583072505891323,
0.027095798403024673,
0.026551619172096252,
0.0626247301697731,
... |
<p>How do I find the correlation coefficient of two variables with unequal number of data using Excel? And do I use the mean as data to calculate? </p> | g4724 | [
0.031161533668637276,
0.019069988280534744,
0.022158509120345116,
-0.026497896760702133,
0.04157821834087372,
0.02739020437002182,
-0.020495392382144928,
0.013653415255248547,
-0.02744107134640217,
-0.06266975402832031,
-0.0419129803776741,
0.03032708540558815,
0.03197639435529709,
-0.0002... |
<p>I am looking to get started using time series (arima) (regression) (etc) evaluating log stock returns in WinBUGs. Does anyone have a simple code to get me jump started?</p> | g65170 | [
0.007574357558041811,
0.004601715132594109,
-0.01897532306611538,
-0.002145014703273773,
-0.02392606995999813,
-0.037952970713377,
0.0472138337790966,
-0.011701395735144615,
-0.064710833132267,
-0.0657215565443039,
0.007440126966685057,
0.023084135726094246,
0.04443873465061188,
0.02324719... |
<p>A <a href="http://stats.stackexchange.com/questions/51237/population-variance-and-sample-variance">recent question</a>, <a href="http://stats.stackexchange.com/questions/54/why-do-us-and-uk-schools-teach-different-methods-of-calculating-the-standard-dev">related question</a>, and <a href="https://maxwell.ict.griffit... | g65171 | [
0.012461459264159203,
-0.02096494287252426,
-0.016049783676862717,
-0.06558199971914291,
0.004193131346255541,
0.042861148715019226,
0.07441829144954681,
0.05849238112568855,
-0.019539477303624153,
0.07377079874277115,
-0.04255448281764984,
0.00706503028050065,
0.04331246390938759,
0.00818... |
<p>Say we have an RBF covariance matrix A and some periodic covariance matrix B for a given dataset. Covariance matrix A says that you believe that points that are close together are somewhat similar, while covariance matrix B implies that your data has some periodicity in it.</p>
<p>Summing (A + B) or multiplying (A ... | g65172 | [
0.0312747098505497,
-0.03864040598273277,
-0.01198294572532177,
-0.04373948276042938,
-0.00006304439739324152,
0.002454870380461216,
0.06680916994810104,
0.000714828900527209,
-0.025284498929977417,
-0.023046154528856277,
-0.01886533759534359,
0.030984647572040558,
0.05837554857134819,
0.0... |
<h2>The general version:</h2>
<p>I need to estimate $f(A | X)$ where $A$ and $X$ are continuous and multivariate. I'd rather do it nonparametrically because I don't have a good functional form in mind and $\hat{f}(A | X)$ needs to be something like unbiased. I wanted to use a conditional kernel density estimator, but ... | g65173 | [
0.0459551103413105,
-0.078862264752388,
-0.007785095367580652,
-0.02967900224030018,
-0.008047087118029594,
-0.08083917200565338,
0.02260940708220005,
-0.01690428890287876,
-0.03762512281537056,
-0.015628227964043617,
0.051774874329566956,
-0.020104188472032547,
0.04445194453001022,
0.0148... |
<p>I want to solve this classification problem. Basically what I have is a sequence of feature vectors $\mathbf{x}_1,\mathbf{x}_2,\dots,\mathbf{x}_N$, and each feature vector is sequential in time. I want to predict the class label $y$ based on the observation of these $N$ feature vectors. The outcome label $y$ can be ... | g65174 | [
-0.01763737015426159,
-0.0178476944565773,
0.022434303537011147,
-0.037634775042533875,
-0.03331495821475983,
-0.04412522166967392,
0.03606268763542175,
0.03132987022399902,
-0.024469107389450073,
-0.008300692774355412,
0.024626512080430984,
0.05618937313556671,
0.02921999804675579,
0.0315... |
<p>I am trying to sample from a posterior having many modes particularly far from each others using MCMC. It appears that in most cases, only one of these modes contains the 95% hpd I am looking for.
I tried to implement solutions based on tempered simulating but this does not provide satisfactory results as in practic... | g65175 | [
0.005401251837611198,
-0.03970685973763466,
-0.015086865052580833,
-0.026381049305200577,
0.0026625271420925856,
-0.02562299557030201,
-0.008037740364670753,
-0.005714225582778454,
-0.025180472061038017,
-0.03466494008898735,
-0.012895704247057438,
-0.006128685548901558,
0.059218697249889374... |
<p>I'm using the GSL statistical package to perform a linear regression on two sets of numbers. I don't have a heavy statistical background, and I'm used to seeing regressions presented in visual format, so I'm having trouble interpreting the results:</p>
<p>Results of Linear Regression:</p>
<pre><code>c0 0.009
c1 0... | g43579 | [
0.0479019396007061,
-0.05131763964891434,
0.0013933012960478663,
-0.01991882175207138,
0.027488697320222855,
-0.023433156311511993,
0.046299491077661514,
0.053365595638751984,
-0.05696187540888786,
-0.011538708582520485,
0.012228470295667648,
-0.006058481056243181,
0.02282583713531494,
-0.... |
<p>The UK Government publishes deprivation scores for geographic areas. Often these scores are converted into ranks and then into quantiles to see if groups of people are more or less deprived than one would expect.</p>
<p>The IMD score is ordinal, Area A may be more deprived than Area B, but we cannot say by how much... | g65176 | [
0.013416223227977753,
-0.06632055342197418,
-0.028017178177833557,
-0.09182115644216537,
-0.02412482537329197,
0.030055126175284386,
-0.018048712983727455,
-0.0009924407349899411,
-0.00006906827911734581,
0.002709263004362583,
0.05268348008394241,
0.03623490035533905,
0.03242453560233116,
... |
<p>I'm currently facing a problem I have been stuck in for almost half a day and I really can't keep this because I have a lot of work to do! It obviously has to do with the birthday problem.</p>
<p>The original birthday problem solves the question of "what is the probability of having at least two persons with the sa... | g65177 | [
0.020974332466721535,
0.016261106356978416,
0.00878838449716568,
0.0034998226910829544,
-0.02794521488249302,
-0.027145763859152794,
0.0646887794137001,
-0.017043473199009895,
-0.009390060789883137,
-0.007268759422004223,
-0.015152030624449253,
0.03553308919072151,
-0.026557564735412598,
-... |
<p>I was just having been assigned a project of conducting sentiment analysis for some document collections. By Googling, a lot of sentiment-related research has popped up. </p>
<p>My questions are:</p>
<ol>
<li><p>What are the major methods/algorithms for sentiment analysis in the field of machine learning and stati... | g214 | [
-0.014775640331208706,
0.005605758633464575,
0.007519264705479145,
-0.07165563851594925,
-0.0001244721352122724,
-0.03920102119445801,
-0.04845099896192551,
0.04700151085853577,
-0.07094066590070724,
0.0374101959168911,
0.012665439397096634,
-0.008959132246673107,
0.07244677096605301,
0.01... |
<p>I have a ($k$-class) classification problem, with of the order of 100 real-valued predictors, one of which appears to have much more explanatory power than any of the others. I'd like to get deeper into the effects of the other variables. However, standard machine learning techniques (random forests, SVMs, etc) seem... | g48215 | [
0.016354259103536606,
0.0007205505971796811,
0.0034790995996445417,
-0.025500889867544174,
-0.013247477822005749,
-0.08568860590457916,
-0.06489776074886322,
0.04812552034854889,
-0.021409176290035248,
-0.0004987128777429461,
0.05000173673033714,
0.009278946556150913,
0.08076904714107513,
... |
<p>I must find a kernel that statisfies as follows:
<img src="http://i.stack.imgur.com/gVBYW.png" alt="enter image description here"> </p>
<p>In the my reference paper, the author suggest gaussian kernel that is
<img src="http://i.stack.imgur.com/uWltv.png" alt="enter image description here"></p>
<p>The purpose of th... | g65178 | [
0.011801300570368767,
0.01942414417862892,
-0.015917273238301277,
-0.04795471951365471,
-0.009783994406461716,
-0.022351060062646866,
-0.021980823948979378,
0.011828672140836716,
-0.031569451093673706,
0.03811778873205185,
-0.015780776739120483,
0.03182191774249077,
0.03702700510621071,
0.... |
<p>As I am trying to automate the process of evaluating models for my prediction problem, I would like to verify the following concerning the process of creating a model consisting of multiple predictor variables for predicting a response variable.</p>
<p>Assume that polynomial regression is promising for solving our ... | g65179 | [
0.00031881689210422337,
-0.051929764449596405,
0.017646996304392815,
-0.014241562224924564,
0.04450133442878723,
-0.06916330754756927,
0.04192756116390228,
0.04959017410874367,
0.0031489471439272165,
0.005467626731842756,
-0.024041712284088135,
0.023400768637657166,
0.04131529852747917,
0.... |
<p>I have seen a few research articles which claim that the classical neural networks usually lacks satisfactory generalization ability, which usually results in an imprecise predictions, and Bayesian regularized ANNs (BRANNs) are more robust than standard back-propagation nets and can reduce or eliminate the need for ... | g23664 | [
0.027781443670392036,
0.03273739665746689,
0.008317112922668457,
0.013010283000767231,
0.010789225809276104,
-0.041576240211725235,
0.03896692767739296,
0.035167720168828964,
0.006870345678180456,
-0.0382499061524868,
0.006758682895451784,
0.03214244171977043,
0.016042090952396393,
-0.0010... |
<p>I have models like this:</p>
<pre><code>require(nlme)
set.seed(123)
n <- 100
k <- 5
cat <- as.factor(rep(1:k, n))
cat_i <- 1:k # intercept per kategorie
x <- rep(1:n, each = k)
sigma <- 0.2
alpha <- 0.001
y <- cat_i[cat] + alpha * x + rnorm(n*k, 0, sigma)
plot(x, y)
m1 <- lm(y ~ x)
summ... | g65180 | [
-0.033228013664484024,
-0.05837049335241318,
-0.00877854973077774,
-0.07866185903549194,
0.04559912532567978,
0.0020381256472319365,
0.0245304387062788,
-0.004631874151527882,
-0.05667198821902275,
0.006176336668431759,
0.00037462732871063054,
0.024263180792331696,
0.06523780524730682,
0.0... |
<p>I was reading this paper related to sparse inverse covariance estimation of a gaussian distribution <a href="http://arxiv.org/pdf/0903.5463v3.pdf" rel="nofollow">http://arxiv.org/pdf/0903.5463v3.pdf</a>.</p>
<p>The paper says that lets say I have some variables $x_1 ... x_N$ following multivariate gaussian distribu... | g65181 | [
0.004218466114252806,
-0.07562562078237534,
-0.02304994873702526,
-0.04939717799425125,
-0.011402742005884647,
0.054679855704307556,
0.0009836269309744239,
0.005034873727709055,
-0.003938066307455301,
0.02139168605208397,
-0.03368224948644638,
0.02358998730778694,
0.033422164618968964,
0.0... |
<p>In the paper <a href="http://charuaggarwal.net/outl.pdf" rel="nofollow"> Outlier Detection for High Dimensional Data</a> at the beginning of section 1.3 Is written: </p>
<p><em>Each attribute of the data is
divided into $\phi$ equi-depth ranges. Thus, each range contains
a fraction f = 1 /$\phi$ of the records.</e... | g65182 | [
0.03722935914993286,
0.017608750611543655,
-0.01891249604523182,
-0.07101712375879288,
0.05599607154726982,
0.0012896652333438396,
0.04494180902838707,
0.00967384409159422,
-0.08484290540218353,
-0.03673989325761795,
-0.03654259443283081,
0.044852837920188904,
0.0021800859831273556,
-0.048... |
<p>I have an experiment where I expect a certain genomic location to influence gene expression levels of nearby genes. I have data for expression levels (Agilent 4x44 microarrays, Drosophila) in two groups - one where I expect expression to be affected and the other wild-type and I would like to run a test for overrepr... | g65183 | [
-0.0029093611519783735,
-0.012053512036800385,
-0.017822735011577606,
-0.05640792474150658,
-0.04230179265141487,
-0.020581532269716263,
0.07593221962451935,
0.029605044052004814,
-0.03241247683763504,
-0.034498509019613266,
0.012001022696495056,
0.0416441336274147,
-0.03496800735592842,
0... |
<p>I am trying to understand when to use a random effect and when it is unnecessary. Ive been told a rule of thumb is if you have 4 or more groups/individuals which I do (15 individual moose). Some of those moose were experimented on 2 or 3 times for a total of 29 trials. I want to know if they behave differently wh... | g23667 | [
-0.01129788625985384,
-0.05171968787908554,
-0.011124847456812859,
-0.04244453087449074,
0.011626454070210457,
0.022647101432085037,
0.06186751276254654,
0.00008690558752277866,
-0.040379442274570465,
-0.03725201264023781,
0.0019815918058156967,
0.03135542944073677,
-0.013001173734664917,
... |
<p>I'm a complete beginner when it comes to R and decision trees, but I was asked to take a look at this to see if this was a viable solution for my data. So please excuse me if I say completely wrong. </p>
<p>This kind of goes along with this previous <a href="http://stats.stackexchange.com/questions/1292/what-is-the... | g43598 | [
0.021933764219284058,
-0.033439118415117264,
0.0053340960294008255,
-0.024041850119829178,
0.02730020508170128,
-0.06058736890554428,
0.044775523245334625,
0.034678880125284195,
-0.007993221282958984,
-0.0046292939223349094,
-0.030058778822422028,
0.04958725720643997,
0.052015531808137894,
... |
<p>In many queuing models it is assumed that the service time follows an exponential distribution with parameter $\mu=1/\lambda$, where $\lambda$ is the average rate of service. An example might be a bank teller who, on average, is able to service customers at a rate of 1 every 10 minutes.</p>
<p>This assumption is ob... | g65184 | [
0.008060206659138203,
0.05043334886431694,
0.003901546122506261,
-0.00821740459650755,
0.01907065138220787,
0.021781567484140396,
0.000004845993316848762,
-0.001237774034962058,
0.005460016429424286,
0.014982424676418304,
-0.011554310098290443,
-0.05480128526687622,
0.009852990508079529,
0... |
<p>I have a simple model:</p>
<p>$A$ is hypothesized to be a predictor / regressor / explanatory / input variable</p>
<p>$B$ is hypothesized to be the response / regressand / explained / outcome variable</p>
<p>So, the relationship looks something like:</p>
<p>$A\longrightarrow B$</p>
<p>Additionally, $C$ is hypot... | g65185 | [
0.020131265744566917,
-0.01237114891409874,
-0.006952662020921707,
-0.02443494088947773,
0.02313363552093506,
-0.02660232037305832,
0.005315852351486683,
0.05263044685125351,
0.022018466144800186,
-0.04815670847892761,
0.003985210787504911,
0.002033935161307454,
0.021374864503741264,
0.060... |
<p>I am analyzing data using path analysis and I am hoping someone here can help. </p>
<p>In my model, I am looking at predictors of a variable, $Y$. In the path model, $Y$ has 4 significant predictors lets call them $A$, $B$, $C$, and $X$ (path coefficient $X$ to $Y$ is $-.16$ which is significant). Of importance, $... | g65186 | [
0.06164594367146492,
-0.0462644062936306,
0.01601325534284115,
-0.01980387419462204,
0.02655711956322193,
-0.012449447065591812,
0.10055852681398392,
0.008613107725977898,
-0.0316426120698452,
-0.008382609114050865,
0.03414928913116455,
-0.006498383823782206,
-0.007259788922965527,
0.00058... |
<p>I am a software developer working on A/B testing systems. I don't have a solid stats background but have been picking up knowledge over the past few months.</p>
<p>A typical test scenario involves comparing two URLs on a website. A visitor visits <code>LANDING_URL</code> and then is randomly forwarded to either <co... | g43601 | [
-0.000750560371670872,
-0.006513801869004965,
-0.008981469087302685,
-0.026726441457867622,
-0.0025009745731949806,
-0.02590714767575264,
0.06017317622900009,
0.03825189545750618,
-0.036802589893341064,
-0.02598939649760723,
0.06782317906618118,
0.037987612187862396,
0.03003298118710518,
0... |
<p>I have an independent variable is a manipulation/predictor which is applied in increasing degrees of strength across groups. The independent variable alters the amount of variation in the dependent variable. </p>
<p>Because we are looking at variance, I cannot use Spearman's Rho to calculate correlation without a w... | g43604 | [
-0.049449630081653595,
-0.024968812242150307,
-0.01764851249754429,
-0.04889138042926788,
0.040361013263463974,
-0.021727679297327995,
0.041738178580999374,
0.01612938567996025,
0.0057031502947211266,
0.008192605338990688,
0.031613633036613464,
0.021643582731485367,
-0.03330710157752037,
0... |
<h3>Background Context:</h3>
<p>I am amazed at the complex statistical questions people ask on this site and I have learnt a lot from them. Thank you all!</p>
<p>However, I have focused on correlation because it is the easist method to understand for a person like me who has no formal training in statistics but is re... | g43605 | [
0.06914401054382324,
-0.03370412439107895,
0.020726080983877182,
-0.04793271794915199,
-0.007125924341380596,
-0.003678773995488882,
0.03592140972614288,
0.011497166939079762,
-0.013481690548360348,
-0.04630283638834953,
0.062417320907115936,
-0.023802857846021652,
-0.02308633364737034,
-0... |
<p>A survey was made where people chose what they use a certain smiley to represent and entered their country of origin. I have recoded the text responses to numeric. </p>
<p>What form of analysis should be used (preferably in SPSS) to check the level of correlation between where the people come from and the represent... | g23679 | [
0.01827974058687687,
-0.014367076568305492,
-0.015374064445495605,
-0.052826400846242905,
-0.022526629269123077,
-0.006218998227268457,
0.06386912614107132,
0.025100870057940483,
0.014298047870397568,
-0.030037643387913704,
0.019117482006549835,
-0.021598422899842262,
0.12837469577789307,
... |
<p>Suppose $ X_t = (\alpha + \beta{t})S_{t} + e_{t}$. </p>
<p>Define $C_{12} = 1 - B^{12}$ as the backshift operator. </p>
<p>Assume $ S_{t}=S_{t-12}$ for all $t$. </p>
<p>Assume that $e_{t}$ is white noise. </p>
<p>Is $C*X_{t}$ stationary? If not, give a different backshift operator that makes the series stationa... | g65187 | [
0.03513668105006218,
0.023267725482583046,
0.0048235091380774975,
-0.021053871139883995,
0.06485580652952194,
-0.02832638844847679,
0.04010078310966492,
-0.004705893341451883,
-0.0361466184258461,
0.04926792532205582,
-0.06632465869188309,
0.06234217435121536,
-0.04621753469109535,
0.04429... |
<p>Can someone give an explanation for why the t-test "happens"? I was taught to use the t-test when you don't know the population standard deviation (i.e., you only know the standard deviation of your sample), but I'm not sure why that would make it different from a z-test.</p> | g65188 | [
0.04161766543984413,
0.03365417942404747,
-0.006175673566758633,
0.00014358769112732261,
0.0036543391179293394,
0.0085831917822361,
0.08699812740087509,
0.058370430022478104,
0.003151628654450178,
-0.03398588299751282,
0.026552274823188782,
-0.01585426926612854,
0.06799989938735962,
-0.003... |
<p>I've encountered this sentence while reading an <a href="http://news.sciencemag.org/scienceinsider/2011/09/survey-european-phd-students-und.html?rss=1" rel="nofollow">article on sciencemag.org</a>.</p>
<blockquote>
<p>In the end, responses from just 7600 researchers in 12 countries were included because the remai... | g65189 | [
0.030195550993084908,
0.0587058886885643,
0.029611418023705482,
-0.020487166941165924,
0.03283216804265976,
0.020707296207547188,
0.014195643365383148,
0.025873415172100067,
0.008398212492465973,
-0.0120761189609766,
0.05544577166438103,
-0.01957172341644764,
0.05007345601916313,
-0.006527... |
<p>Is there a recommended n to test for Spearman's rank correlation? I have 2 lists of around 10,000 items. I read that Spearman's rank correlation is fine between 10-30 , can I use spearman to compare ranked list of 100 or even 1000?</p>
<p>Thanks </p> | g23681 | [
0.021979227662086487,
-0.030284415930509567,
0.011608229950070381,
-0.048100925981998444,
0.02796969562768936,
0.009722955524921417,
0.011314268223941326,
0.011770700104534626,
0.03298263996839523,
0.016149455681443214,
0.007622741628438234,
0.03139445185661316,
-0.02358752116560936,
0.023... |
<p>I am interested in taking the following model to my data:</p>
<p>M = X + Z + XZ</p>
<p>Y = X + M</p>
<p>Where Y = outcome; M = mediator; X = treatment; Z = moderator; XZ is treatment-moderator interaction</p>
<p>This corresponds with Hayes' model 2 (<a href="http://www.ats.ucla.edu/stat/stata/faq/modmed.htm#mode... | g65190 | [
-0.01494777575135231,
-0.046983834356069565,
-0.029811294749379158,
-0.06752390414476395,
0.0279996320605278,
-0.02688666805624962,
0.03432408720254898,
0.024733394384384155,
0.00008209046791307628,
-0.03438790887594223,
0.0021657301113009453,
-0.006909520830959082,
0.04447216913104057,
0.... |
<p>I have a situation where I want to test for differences between rows and columns in my data frame:</p>
<pre><code> Sample variant Cond1A Cond1B Cond2A Cond2B
Sample1 1 2000 2311 2323 2324
Sample1 2 2424 1313 2... | g23682 | [
0.03587023541331291,
-0.01903681643307209,
0.023012472316622734,
-0.039031073451042175,
0.01133052445948124,
-0.05958553031086922,
0.057184215635061264,
-0.01203162968158722,
-0.05581512674689293,
-0.054885514080524445,
-0.007500151172280312,
0.03913082554936409,
0.011344119906425476,
0.03... |
<p>I've been working on a project on measuring polls' accuracy in complex contexts (more than two candidates) where there are a small number of inaccurate polling data points. </p>
<p>I thought it would be the case to work on the probabilities instead of focusing on the real differences between the estimated and the a... | g720 | [
-0.06091814860701561,
-0.006952632684260607,
-0.0011272812262177467,
0.035924386233091354,
-0.033155202865600586,
-0.018503952771425247,
-0.021947618573904037,
0.017945382744073868,
-0.0318986177444458,
0.02320774458348751,
-0.005929730366915464,
-0.05755547434091568,
0.03443005681037903,
... |
<p>The R function <code>chisq.test</code> allows a 'vector of probabilities' to be set with the <code>p</code> argument. Is there an equivalent for <code>fisher.test()</code>?</p>
<p>I'm trying to test whether there's a significant difference between the proportion of people in three unequally-sized groups who studied... | g23683 | [
-0.02406994067132473,
0.01620154269039631,
0.013717200607061386,
-0.05069933086633682,
0.0281954538077116,
-0.0262160561978817,
0.0128202298656106,
0.03910800442099571,
-0.0357992984354496,
0.007385705132037401,
-0.0017009265720844269,
0.01813885197043419,
0.014441202394664288,
0.019685443... |
<p>I am in a scenario where I am trying to forecast 2014 call volume in a call center based on prior call volumes in 2013 and 2012. How do I difference 2014 call volume, and how do I lag 2012 and 2013 call volume so that I can run a statistically sound model? Also I have access to data on these call volumes by week a... | g23687 | [
-0.010220219381153584,
-0.016711382195353508,
-0.005508203990757465,
-0.014219057746231556,
-0.008968734182417393,
-0.022583521902561188,
0.03170737251639366,
-0.009066520258784294,
-0.021960413083434105,
-0.007041492033749819,
0.02598525397479534,
-0.03380521014332771,
0.08848991990089417,
... |
<p>I am trying to fit an arima model to data below. The best model seems to be ARMA(2,2) with the first AR and MA components zero to me. However, it does not quite satisfy me. I am looking for any ideas to lead me to a better model. Data plot, acf, pacf and fitted model results are below</p>
<pre><code> [1] 3.800731... | g65191 | [
0.03101201355457306,
-0.08751465380191803,
0.016660477966070175,
-0.049171850085258484,
0.036986421793699265,
-0.008332927711308002,
0.07616185396909714,
-0.025363739579916,
-0.027853302657604218,
0.02852075733244419,
0.038388729095458984,
0.04953291267156601,
0.06047462299466133,
-0.04815... |
<p><em>We've got given annual results of two stock companies described with following values:</em></p>
<p><strong><em>Company X:</strong> expected value $\mu_X=0.05$, standard deviation $\sigma_X=0.02$</em></p>
<p><strong><em>Company Y:</strong> expected value $\mu_Y=0.07$, standard deviation $\sigma_Y=0.03$</em></p>... | g65192 | [
0.061837803572416306,
-0.019822489470243454,
-0.03540925681591034,
0.046672720462083817,
0.030433503910899162,
0.0030576407443732023,
0.03538726270198822,
0.004651614930480719,
0.005072457250207663,
-0.03506675735116005,
0.052045874297618866,
-0.014413069002330303,
-0.000318084261380136,
-... |
<p>Both general advice and advice specific to my case below is welcome.</p>
<p>I'm trying to contruct a Bayesian network with 20-30 continuous variables. I have 15 locations sampled, with 14 time points each. The dataset will grow over time, but I have a feeling that there will be severe underfitting for quite a whi... | g23689 | [
0.003662424860522151,
0.015801241621375084,
-0.01653626561164856,
-0.046799007803201675,
-0.0517798513174057,
-0.015633191913366318,
0.010297858156263828,
0.002748681465163827,
-0.041445448994636536,
-0.007657378911972046,
0.04427910968661308,
-0.0070372894406318665,
-0.03423915430903435,
... |
<p>I was advised to post this question here rather than in the math stack exchange. So here it is: I am interested in an upper bound on mutual information that I have been encountering frequently in the statistics and probability literature. I have yet to see the "purest" form of the inequality, so I will attempt to st... | g23690 | [
-0.021206971257925034,
-0.004541876260191202,
-0.007813078351318836,
-0.018999576568603516,
-0.005235033575445414,
-0.010886579751968384,
0.049107883125543594,
-0.02712375484406948,
-0.02169451303780079,
-0.004989405162632465,
-0.020312365144491196,
0.043527305126190186,
0.006659619975835085... |
<p>I have a basic question regarding pattern learning, or pattern representation. Assume I have a complex pattern of this form, could you please provide me with some research directions or concepts that I can follow to learn how to represent (mathematically describe) these forms of patterns? in general the pattern doe... | g65193 | [
-0.01002945750951767,
0.011259863153100014,
0.01716996729373932,
-0.020106172189116478,
0.002655478660017252,
0.0007464270456694067,
0.03642736002802849,
0.0056591215543448925,
0.017828186973929405,
-0.11308582127094269,
-0.01925623044371605,
-0.04426851496100426,
0.1066749170422554,
0.024... |
<p>This is a fairly simple question about raw data in Excel. I have a survey asking respondents to rate 17 questions on a rating scale from 1 to 5. The goal is for individuals who answer the survey to be anonymous. There are also demographic questions. For the sake of anonymity, we don't want someone to be able to matc... | g65194 | [
-0.007703978102654219,
0.026846153661608696,
0.022920377552509308,
-0.001592500600963831,
-0.0047569358721375465,
-0.010216126218438148,
-0.029049161821603775,
-0.01608129031956196,
-0.024845683947205544,
-0.012050890363752842,
0.0008230364765040576,
0.008145678788423538,
0.03027387894690036... |
<p>what are best ways to interpolate time series? I have three data points(1980, 1990 and 2001) and I need to interpolate them. Using R na.approx doesn't seem to be what I need since the data I need to interpolate is population and it is very unlikely for it to move linearly.</p> | g65195 | [
0.037336062639951706,
-0.009906480088829994,
0.04783787205815315,
-0.026943804696202278,
-0.04914926737546921,
0.05596223101019859,
0.0394379086792469,
0.027025284245610237,
-0.08984816074371338,
-0.00513898441568017,
0.014441507868468761,
0.018902676180005074,
0.01728873699903488,
-0.0290... |
<p>Lets say that I have "y" that I want to model with linear regression. "x" and "z" are the things I'm interrested in showing folks, but I also have things that I want to adjust for, but not really show in my plot.</p>
<p>Now, I would like to show my coefficients in a plot, but I would like to keep the things I adjus... | g65196 | [
0.01822085864841938,
-0.0198994018137455,
0.0018975064158439636,
-0.05436234548687935,
0.012826597318053246,
-0.045391470193862915,
0.047861773520708084,
-0.009949654340744019,
-0.05435864254832268,
-0.03129010647535324,
0.006434535142034292,
0.046250589191913605,
0.03493674099445343,
0.03... |
<p>Everything I've read about Buhlmann-Straub credibility assumes a fixed $\theta_i$ (the unknown parameter that $X_{ij}$, the variable of interest, depends on). Does anyone know of a version where theta can vary, say with time?</p> | g65197 | [
0.03654833137989044,
-0.005067481193691492,
0.0042496235109865665,
0.014306657016277313,
0.022605136036872864,
-0.01861494407057762,
-0.008977874182164669,
-0.010497821494936943,
-0.037424005568027496,
0.04482022672891617,
-0.003619597991928458,
0.05233496055006981,
-0.03413844481110573,
-... |
<p>I want to make forum software with instant runoff voting instead of polls, but I don't know what to do in edge cases.</p>
<p>Should I allow voters to not weigh certain choices at all? If there are 5 choices and they only care about 3, and don't want weigh the remaining choices, should I allow that?</p>
<p>If I all... | g65198 | [
0.005920130293816328,
0.01733529381453991,
-0.006638798397034407,
-0.0006758378003723919,
0.029856881126761436,
0.04570968449115753,
-0.01557218749076128,
-0.0049913302063941956,
-0.028937378898262978,
0.02191687561571598,
-0.013814253732562065,
-0.05490810051560402,
-0.012247647158801556,
... |
<p>If I'm not wrong both "quasi" and "pseudo" denote the same thing, namely the optimization under wrong distributional assumptions. Moreover I think that the terms are not restricted to the assumption of normality. Is there an experienced reader who can confirm this? Cheers!</p> | g65199 | [
0.024074887856841087,
0.09077669680118561,
0.025376902893185616,
-0.012144367210566998,
0.013294453732669353,
-0.05118568614125252,
0.02108372189104557,
-0.020194269716739655,
-0.01968209818005562,
0.002337419195100665,
-0.09443987160921097,
-0.010534952394664288,
-0.010909362696111202,
0.... |
<p>I haven't studied statistics for over 10 years (and then just a basic course), so maybe my question is a bit hard to understand.</p>
<p>Anyway, what I want to do is reduce the number of data points in a series. The x-axis is number of milliseconds since start of measurement and the y-axis is the reading for that po... | g65200 | [
0.06366125494241714,
0.025285623967647552,
0.007735915016382933,
-0.019460510462522507,
-0.022516807541251183,
-0.06800958514213562,
0.05997191369533539,
0.007603021338582039,
-0.052703630179166794,
-0.022960178554058075,
-0.017911357805132866,
0.0407906249165535,
0.06908369809389114,
0.00... |
<p>I have conducted a research on four independent groups of students; one experimental and one control group at two levels. The design of the study was like a pre-test and post-test.
I want to detect the effects of acquiring how to use one variable (metacognitive strategies) on another variable (self-regulation). To ... | g65201 | [
-0.015505509451031685,
-0.00851515680551529,
-0.020131349563598633,
-0.0607161670923233,
0.012168158777058125,
-0.03945024684071541,
0.04152363911271095,
0.015787208452820778,
0.03527132049202919,
-0.017260044813156128,
-0.004385585431009531,
0.025082509964704514,
0.02343875914812088,
0.04... |
<p>I carried out factor analysis on 31 5 likert-scale questions which represent my 6 constructs. </p>
<p>The results showed 6 factors, consistent with my hypothesis but the analysis grouped my questions differently from what I expected. For example when I wrote the survey I dedicated the first 5 questions as measur... | g65202 | [
-0.0035490745212882757,
-0.09589081257581711,
0.01177549734711647,
-0.05012109875679016,
0.04060576111078262,
0.025195742025971413,
0.04636695981025696,
-0.030637789517641068,
0.021347468718886375,
-0.046624042093753815,
0.026816263794898987,
0.0017731853295117617,
-0.007149526383727789,
0... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.