question stringlengths 37 38.8k | group_id stringlengths 2 6 | sentence_embeddings listlengths 768 768 |
|---|---|---|
<p>Suppose I am interested in the follows:
I have county-level data. For each county, I know the share of the population that was born from one parent and the share of the population that was born from two. Suppose I am interested in the impact of the black population on tax revenues. In particular, suppose I am als... | g62661 | [
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<p>Unfortunately nobody seem to know the answer to my first question...does anyone know how to compute a conditional expectation on absolute value? </p>
<p>Let
$$\boldsymbol y
=
\begin{bmatrix}
\boldsymbol y_{a}^{\top} \\
\boldsymbol y_{b}^{\top}
\end{bmatrix}
$$</p>
<p>$$\boldsymbol y \sim \mathcal{N}({\boldsymbo... | g62662 | [
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<p>I have a regression with typical Stata output. The only independent variable is a dummy (=1 if person bought certain item). How can I find how many people in the sample bought the item? </p> | g19836 | [
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<p>If I have a linear regression of the form:</p>
<p>$$y \sim 1+\beta_1x_1 + \beta_2x_1x_2,$$</p>
<p>where $x_2$ is a Boolean variable depending on another variable $x_{2cont}$, a positive variable:</p>
<p>$$x_2 = \begin{cases} 1 & \mbox{if } x_{2cont} > 5 \\
0 & \mbox{if } 0 < x_{2cont} \le 5. \end{ca... | g49892 | [
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<p>I have a df like this:</p>
<pre><code> Rate Gender
7 Male
5 Female
10 Male
20 Male
9 Female
</code></pre>
<p>Etc</p>
<p>I need to run an analysis to determine significance of gender on the rate. I'm really new to this, any i... | g19840 | [
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<p>This one is straightforward. I am trying to find a good documentation of the phi correlation. There is a Chi-Square Statistic to test the significance of the the correlation coefficient, I am hoping that the document would have good documentation of this, how many degrees of freedom for the critical value and all th... | g16229 | [
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<p>I have a data set with about ~2000 data points. Of these ~1000 actually have features/data. (All 2000 data points have an outcome)</p>
<p>Where there's no data, there <em>is</em> very likely a signal. In other words, if I'm not able to get data for that data point, that's significant in and of itself, and there is ... | g62663 | [
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<p>Suppose I have a fruit stand where I sell oranges. Every day I have an average of $\lambda$ people (Poisson distributed) each buying a normally distributed weight quantity of oranges with mean $\mu$ and standard deviation $\sigma$.</p>
<p>What's the mean and variance of the number of pounds of oranges I sell per da... | g19842 | [
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<p>I think this is more of a stats advice than code question so I've posted here rather than SO. My data looks like this (~300 more sample rows).</p>
<pre><code>> head(nest)
GroupA GroupB SubA SubB Treat
1 45 100 3 6 Pos
2 43 80 2 5 Neg
3 64 70 0 4 Neg
4 75 7... | g19844 | [
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<p>I'm confused about multistep forecasting from VECM model for 2 cointegrated series.
The model is pretty simple, in error-correction form:
$$ \Delta x_{t+1} = \alpha_1 (y_t - \beta x_t -\beta_0) +\varepsilon_{1,t}, \\
\Delta y_{t+1} = \alpha_2 (y_t - \beta x_t -\beta_0) +\varepsilon_{2,t}. $$</p>
<p>Where $y_t - \be... | g62664 | [
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<p>I have a multicollinearity problem is a linear regression model and ridge regression was suggested as a solution. So I have spent quite some time researching different ridge regressors in the literature (there's at least a dozen), however in the course of my research I have found that Principal Components Regression... | g62665 | [
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<p>I'm not good at Statistics but I need to use it to summarize my case study.
So I consult with a person who're good at Statistics. He suggested that
My data is discrete because all the values are integer and some are duplicated as shown below. I want to find correlation between x and y of the two data sets below. In ... | g62666 | [
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<p>I am having an input data set( 14 x 250 ) which has attached a labels set ( 1 x 250 ).</p>
<p>The labels set is discrete( 0 vs. 1). The problem is that the each one of the 14 characteristics are continuous. For example, for characteristic 1 I am having :</p>
<pre><code>10.18 ; 11.18 ; 9.89 ; 22.45
0 ; 1 ;... | g19850 | [
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<p>In follow up to a question posted here: <a href="http://stats.stackexchange.com/questions/12484/constrained-linear-regression-through-a-specified-point/12511#12511">Constrained linear regression through a specified point</a></p>
<p>What are some ways that we can tell if a simple linear regression model is "good" wh... | g62667 | [
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... |
<p>I'm having trouble understanding what this problem is asking for. Could someone clarify how to obtain posterior probabilities using backward/forward probabilities?</p>
<p><img src="http://i.stack.imgur.com/TPsfe.png" alt="Problem"></p> | g62668 | [
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<p>I have a question about how to analyze some questionnaire data. </p>
<p>I have three different participant groups: A,B,C and each group people did the same questionnaire. </p>
<p>So I have a total score for that questionnaire for each participant. </p>
<p>I am trying to find the correlation between these scores w... | g62669 | [
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... |
<p>I'm trying to analyze for any trends in what I consider to be low observations or counts.</p>
<p>Let's say you have a bus service with the following commuters:</p>
<pre><code>year average count
2001 12
2002 15
2003 17
2004 13
2005 18
2006 12
2007 9
2008 12
</code></pre>
<p>The above numbers are ... | g62670 | [
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<p>I have a variance test based outliers detection algorithm. The algorithm is exposed with a visual application where the user can configure its parameters namely the multiplier. </p>
<p>The question is what is the range of values for the algorithm multiplier? </p>
<p>the algorithm basically is calculating the mean ... | g16232 | [
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<p>When using Q-Q plot, why do we choose the empirical distribution $F_n(x) = \frac {\#\{y \in S \mid y \le x\}} n$, $S$ is sample, for comparison with normal?</p>
<p>Let $S$ be our sample of size $n$. Then we form the empirical distribution $F_n$ as defined above. We then use a Q-Q plot to compare $F_n$ to $N(0,1)$... | g49650 | [
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<p>I have 2 different regression algorithms trained on the same dataset. I want to know if on a test set one of them performs significantly better than the other -- or at least if they are significantly different. What test do I use ? I am looking for something similar to McNemar's test that exists for classification a... | g62671 | [
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<p>I read this statement on the Wikipedia article about Credible Intervals and it seems dubious to me. Although it has a reference associated with it, the book is not available to read online.</p>
<blockquote>
<p>It is possible to frame the choice of a credible interval within decision theory and, in that context, a... | g62672 | [
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<p>When discussing the Poisson process with changing point (Carlin, Gelfand and Smith, 1992), the model is assumed as</p>
<p><img src="http://i.stack.imgur.com/FCGgE.png" alt="enter image description here"></p>
<p>I am not quite clear about the derivation of conditional posterior distribution based on the above model... | g62673 | [
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<p>How would this influence the accuracy of the SVM model?</p>
<p>Let's suppose that I have one variable which max value is 100 and minimum is 0. </p>
<p>Currently, I send it to SVM as a single continuous feature, for example, if the value is 8 I send it as 0.08.</p>
<p>I am wondering though, what would happen if I ... | g62674 | [
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<p>I am attempting to find a way to perform a power analysis for a higher order repeated measures ANOVA where all factors are within-subjects (i.e., there are no between-subjects factors). I have looked extensively for a way to do this using existing tools like SPSS, or G*Power and other packages but have not found any... | g19858 | [
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<p>When performing model validation and we are dropping the least significant explanatory variables until we find the optimum model where all remaining variables are significant, how does one go about dropping a particular "unimportant level" within a nominal variable? In my output below I have run a Neg. bin. GLM inor... | g108 | [
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<p>If I understand correctly, a distribution in the exponential family...
$$\underline X\sim f_{\underline\theta}(\underline x) = exp\{\sum\limits_{i}\eta_i(\underline\theta)T_i(\underline x)-B(\underline\theta)\}~h(\underline x)$$
...where $\underline\eta(\centerdot)$ is a (possibly vector valued) parameter, $\under... | g29015 | [
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<p>I have four different time series of hourly measurements:</p>
<ol>
<li>The heat consumption inside a house</li>
<li>The temperature outside the house</li>
<li>The solar radiation</li>
<li>The wind speed</li>
</ol>
<p>I want to be able to predict the heat consumption inside the house. There is a clear seasonal tren... | g42617 | [
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<p>Suppose that an investigator has collected some longitudinal data from each of the $n$ subjects, and that a correlation coefficient is computed on the data between any pair of subjects, leading to totally $n(n-1)/2$ correlation coefficients. After converting those correlation coefficients into $z$-values through Fis... | g62675 | [
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<p>I am forecasting data using ARIMA. I would like to know if there is any test to check if seasonal differencing is needed in the ARIMA model.</p>
<p>I know R uses Canova Hansen test, but does MATLAB provide anything similar to that? Also, is there an easy way of predicting if seasonally differenced model would give ... | g29037 | [
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<p>If $\mathrm{E}\left(X\right)<\infty$ does that imply $\mathrm{E}\left(X|Y\right)<\infty$? How about vice versa? </p>
<p>I'm thinking if we condition on an event (say $Y>2$) then if we have $\mathrm{E}\left(X\right)<\infty$ we can somehow use the theorem of total expectation to bound the other terms. Any... | g62676 | [
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<p>An L1 estimator minimizes the absolute difference between $Y$ and $x\beta$, whereas an M-estimator minimizes some function of the residuals. But the objective function needs to be differentiable right? Then why is an L1-estimator a special case of M-estimator?</p> | g19866 | [
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-0.052756160497665405,
0.021609993651509285,
0.005053883418440819,
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0.004827085882425308,
-0.05350164324045181,
0.04414014145731926,
0.007474416866898537,
0.0... |
<p>How can I convert the [-1;1] bound cross correlation value to a probability [0;1].
Cross correlation measures the similarity of two signals / images A,B, I aim at expressing this in the probability that signal A is equal to signal B.
Essentially, cross correlation has been used in the field of bio-image processing a... | g62677 | [
0.012409836985170841,
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<p>I have used the Bayes Net Toolbox to build a small network, which consists of 3 nodes and is shown below.</p>
<p><img src="http://i.stack.imgur.com/KkC1t.png" alt="enter image description here"></p>
<p>Node 1 is a Bernoulli random variable, node 2 is a Gaussian random variable and node 3 is a softmax random variab... | g62678 | [
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0.027663903310894966,
0.03381870314478874,... |
<p>If r between X and Y is 0.74, then r-squared is 55%.</p>
<p>According to many 'rules of thumb' and others, the effect size (in this case r) is considered 'moderate' or 'medium'. </p>
<p>As such, only 55% of the variance in Y can be explained by X. The remaining 45% remain unexplained.</p>
<p><strong>Question 1: G... | g19867 | [
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<p>I am facing the following dilemma. I am aware of how to handle the one-sided Chi-distribution, but I am falling victim to how to handle degrees of freedom. Let me clarify with an example what I mean.</p>
<p>I have the following obseverd and expected values:</p>
<pre><code>[Observed Data]
#Periods CountryI ... | g38957 | [
0.0311159398406744,
0.055413175374269485,
-0.009409721940755844,
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0.05789605528116226,
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0.059116557240486145,
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0.008748281747102737,
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<p>I shall be grateful for an explanation of how to apply fuzzy logic based reasoning for the following example: I have 3 crisp sets of features = color, shape and texture. The objects are red ball, red box, green cup and blue cup. </p>
<p>Rule can be:</p>
<p>R1: If color is red and shape is circular and texture is ... | g22475 | [
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0.01115975622087717,
0.06273308396339417,
0.06007... |
<p>I am conducting an experiment on comparing the training effects on young and older adults (meaning it will be 2 independent groups). This also means it will be a repeated measure (within groups) because I will test the score before and after training. I think I should use mixed 2 way ANOVA. (Am I right?)</p>
<p>How... | g19869 | [
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<p>I am currently analyzing a 34-item standardized survey on Physics expectations. I gathered data from 104 female respondents from a certain school. The survey's supporting literature said that the survey measures 6 specific dimensions, with each dimension corresponding to 5-6 items. My professor asked me to conduct S... | g62679 | [
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... |
<h3>Context</h3>
<p>I have a dataset of 8 categorical variables. And I want to apply Categorical Principal Component Analysis (CatPCA).</p>
<p>Before doing that, I have been advised to look at the transformation plots of all these variables after transforming them into nominal variables. This shows that some variable... | g19870 | [
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<p>I have a large dataset which is made up of responses from 600 shoppers on 15 variables.</p>
<p>When I tally the responses, it comes to 603. I know there were 600 respondents, so I must have recorded the responses of three people twice.</p>
<p>Instead of checking each questionnaire against the dataset, can I run a ... | g62680 | [
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<p>The Kappa ($\kappa$) statistic was introduced in 1960 by Cohen [1] to measure agreement between two raters. Its variance, however, had been a source of contradictions for quite a some time. </p>
<p>My question is about which is the best variance calculation to be used with large samples. I am a inclined to believe... | g42696 | [
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<blockquote>
<p><strong>Possible Duplicate:</strong><br>
<a href="http://stats.stackexchange.com/questions/13850/not-significant-f-but-a-significant-coefficient-in-multiple-linear-regression">Not-significant F but a significant coefficient in multiple linear regression</a><br>
<a href="http://stats.stackexchange.... | g49368 | [
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0.027313994243741035,
0.005472627934068441,
0.023258956149220467,
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0.021545516327023506,
0.0... |
<p>I have performed 61 Pearson correlation analyses between Variable A (buying ice cream) and Variable B (buying yoghurt) in my dataset (n=550). Each correlation is based on a different subset of the data (e.g., separate correlations for males and females; separate correlations for different age groups).</p>
<p>Fortun... | g62681 | [
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0.0... |
<p>I am developing automated trading systems for the stock market. The big challenge has been overfitting. Can your recommend some resources describing methods for measuring and avoiding overfitting?</p>
<p>I started with training/validation sets, but the validation set always gets tainted.</p>
<p>Also, the time seri... | g62682 | [
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<p>I am having serious problems understanding the type of design I have, I would appreciate any help you can give me to understand it:</p>
<p>I have 324 data points, and four factors:</p>
<ul>
<li><code>epoch</code> factor, with three levels.</li>
<li>altitudinal <code>floor</code> factor, with three levels.</li>
<li... | g62683 | [
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0.02966199442744255,
0.0391746461391449,
-0.023508... |
<p>I am conducting an analysis into offending in relation to a time-dependent exposure - onset of heroin use, over a persons life. I am using poisson GEE with offending aggregate to a persons age-year. Many people have experienced time in prison, which means they can't experience the outcome, but are still experiencing... | g62684 | [
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0.06876355409622192,
0.012957381084561348,
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0.025040902197360992,
0.03... |
<p>I tried to search info regarding this fact but I don't really understand why most of the standard goodness of fit tests (e.g. Kolmogorov-Smirnov, Anderson-Darling, a part of the Chi-square test, perhaps!) work only with continuous distributions. Can someone help me?
Thank You.</p> | g62685 | [
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<p>I have collected questions from 10th grade students about genetic engineering before and after learning about the subject and classified the questions based on their cognitive level..</p>
<p>Before learning about the subject, I collected a total of 45 student questions.
I classified 28 of those as "input" (basic) ... | g38972 | [
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0.... |
<p>I have a model of the following form:</p>
<p>$P(Y \mid X) = \,D(\mu,\sigma^2) ~~\text{where}$</p>
<p>$\mu = f(X) ~~\text{and}~~ \sigma^2=g(X)$</p>
<p>where $y$ is the response vector of count data, $X$ is the predictor matrix, $f()$ and $g()$ are linear inverse link functions (I don't mind what they are), and $D$... | g19876 | [
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0.003444210160523653,
0.02897101640701294,
0.026377828791737556,
... |
<p>I got AIC values of all models to identify the best model using R language. As I heard, best model produce the smallest AIC value, but maximum likelihood estimation procedure optimizer should converge.</p>
<p>How can I check whether maximum likelihood estimation procedure optimizer has converged or not in R languag... | g62686 | [
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0.05003557354211807,
0.093341... |
<p>I have a problem with the <code>ezANOVA</code> package using for rm ANOVA or a problem with my statistic design of the experiment (or both ;-))</p>
<p>My file looks like this, </p>
<pre><code>dput(head(reg,20))
structure(list(sample = c(13L, 14L, 15L, 13L, 14L, 15L, 13L,
14L, 15L, 13L, 14L, 15L, 13L, 14L, 15L, ... | g62687 | [
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-0.0009866772452369332,
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0.022935032844543457,
0.041506078094244,
0.019... |
<p>I'm using the randomForest package in R to develop a random forest model to try to explain a continuous outcome in a "wide" dataset with more predictors than samples.</p>
<p>Specifically, I'm fitting one RF model allowing the procedure to select from a set of ~75 predictor variables that I think are important. </p>... | g19878 | [
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... |
<p>[update] It seems I had my question's original title misfocused a bit; concerning the use of partial derivatives I found some explanation/confirmation in <a href="http://en.wikipedia.org/wiki/Partial_derivative" rel="nofollow">wikipedia's partial derivative</a> There it is stated -and explained with a 3-d-picture of... | g38977 | [
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<p>I know that you can have a construct as a dependent variable: MANOVA or MANCOVA. Is it possible for me to have a construct as an independent variable?</p>
<p>I have a construct that consists of 3 variables that I want to use as my independent variable and I have one variable that I want to use as a dependent variab... | g28444 | [
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<p>Is there a way in Excel to create a pivot table with multiple column totals?</p>
<p>Here's column names to demonstrate what I'm trying to do:</p>
<p>Jan | Feb | Mar | Apr | May | Jun | <strong>6 Month total</strong> | Jul | Aug | Sep | Nov | Dec | <strong>6 Month total</strong> | <strong>12 Month total</strong></p... | g38981 | [
0.029348056763410568,
0.002831819001585245,
0.014568217098712921,
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0.016438571736216545,
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0.05799826979637146,
... |
<p>When computing a confidence interval of slope in linear regression, should you use the z- or t-statistic?</p> | g38986 | [
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<p>I have a bit of trouble understanding how to formulate a correct formula in R using the lmerTest-library.</p>
<p>Let’s assume there is an 2x2 in-between design with repeated measurements. Those repeated measurements can also be categorized in two ways: the position and the difficulty.</p>
<p>Therefrom I got the fo... | g62688 | [
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0.02320806123316288,
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-... |
<p>Let there be an exam consisting of <strong>q questions</strong> each of which having <strong>a alternatives</strong> where there's only one correct answer to each question.</p>
<p>Assumptions:</p>
<ul>
<li>The questions are independent; that is, the responses
do not interfere with the responses to other questions.... | g62689 | [
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0.006139578763395548,
0.003500018734484911,
0.0029837070032954216,
0.005086580291390419,
0... |
<p>I am computing binomial probabilities for many parameters. I am using the library scipy.stats: </p>
<pre><code>b = scipy.stats.binom(n,p)
probability = b.pmf(k)
</code></pre>
<p>I have noticed that the result is <code>nan</code> when both n and p are 0. This raises errors in my program, so I replaced nan by 0, sin... | g62690 | [
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<p>For my research paper, I want to measure headache frequency and I asked participants " Since last month how many times you have had headche ? and they gave answers like 2 times, 3, 5, 10, 14 times etc..
I am confused with the type of this data, Shall I treat it as ordinal or interval ?
Thanks alot in advance </p> | g1014 | [
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<p>My sample includes $n$ random observations, while $n-1$ of these observations are in the range (0-1) there is also one observation that gets very high value.
For example, a sample of prices where $n-1$ prices are lower then 1 dollar and one price in the sample is 1000 dollars.</p>
<p><strong>Is the bootstrap estim... | g62691 | [
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0.017552295699715614,
... |
<p>Let $X_1, . . . , X_n$ be an iid sample from $\text{N}(\theta,\sigma^2)$, in which $\sigma^2$ is known and $\theta$ can have the values $0,±1,±2, . . .$, and let $\bar{X}_n^*=\max\{k\in\mathbb{Z}:k\leq \bar{X}_n\}$ be the largest integer smaller or equal than $\bar{X}_n$.</p>
<ol>
<li><p>Show that $\bar{X}_n^*$ is... | g62692 | [
-0.008617869578301907,
0.004888453986495733,
-0.03260725364089012,
-0.019726596772670746,
0.00636580865830183,
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0.015772994607686996,
-0.025397857651114464,
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0.056037936359643936,
-0.03249746561050415,
0.040047917515039444,
-0.03601868823170662,
0.... |
<p>In my test procedure I sequentially take 10 measurements of a recently perturbed physical system, and I often find the first few (between 0 and 4) measurements can be inaccurate because the system has not settled/equilibrated. The initial non-equilibrated measurements may just have less accuracy or show a distinct t... | g62693 | [
-0.0011835652403533459,
-0.004191342741250992,
0.011687375605106354,
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0.0024658755864948034,
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0.07610559463500977,
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0.039563462138175964,
0.02482321299612522,
0.015376347117125988,
0.010170171968638897,
... |
<p>Propensity score matching (and other matching techniques) are used, as far as I have seen, exclusively for identifying causal effects of a treatment (intervention) and particularly where there is a suspicion of selection bias.</p>
<p>However I do not see why they might not be useful for other cases of comparing two... | g62694 | [
0.028552209958434105,
-0.02740597538650036,
0.014929940924048424,
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0.03669244796037674,
0.05024922266602516,
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-0.04946351796388626,
0.05121614784002304,
-0.02639506757259369,
0.020304476842284203,
0.018... |
<p>I have a data frame with each column contains categorical data: 0,0.5,1,-1</p>
<pre><code> T116 T111 T11 T109 T108 T107 T105 T104 T55 T52 T58 T1
cg21277995 1.0 0.5 0.5 0.5 1 0.5 1.0 1.0 1.0 0.5 1.0 0.5
cg01324372 0.0 0.5 0.0 0.5 1 1.0 0.5 1.0 1.0 0.5 1.0 0.5
cg13836638 1.0 0.5 0.0 ... | g38993 | [
-0.0023995002266019583,
0.02321620099246502,
-0.0063951825723052025,
-0.03905199468135834,
0.052101995795965195,
-0.06525381654500961,
0.07186886668205261,
0.003925304859876633,
-0.058242980390787125,
-0.008850007317960262,
-0.04440164193511009,
0.06489638984203339,
0.028859931975603104,
0... |
<p>I have time series data for two firms relating cost to quantity produced and I model the two firms' cost functions separately using OLS:</p>
<p>Firm 1:〖cost〗_1t= β_1+β_2 〖qty〗_1t+ β_3 〖qty〗_1t^2+ β_4 〖qty〗_1t^3+ ε_1t
Firm 2:〖cost〗_2t= β_1+β_2 〖qty〗_2t+ β_3 〖qty〗_2t^2+ β_4 〖qty〗_2t^3+ ε_2t</p>
<p>It is believed the... | g19888 | [
-0.011115079745650291,
-0.0445043221116066,
0.0059193498454988,
0.004245780874043703,
0.04250907525420189,
-0.024183306843042374,
0.0036468617618083954,
-0.014779428020119667,
0.008220840245485306,
0.011717909015715122,
-0.02020546793937683,
0.041324444115161896,
-0.0035582201089709997,
0.... |
<p>For some time already I am studiyng and applying machine learning methods. Recently for some particular problem, where methods like SVM, RF, neural nets etc. failed I got limited success with genetic programming, which was quite new area for me in practice at the moment.
But right now it looks like, I really need to... | g62695 | [
0.002784215845167637,
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0.0403570793569088,
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0.02788502350449562,
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0.037149034440517426,
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-0.06182123348116875,
0.021060293540358543,
0.05588458478450775,
0.08504047244787216,
0.0551072... |
<p>Let $X_1, X_2, \dots, X_n$ be a sample of i.i.d. random variables, with density $$f_\theta=\frac{2}{3\theta}\left(1-\frac{x}{3\theta}\right) $$ for $0 < x < 3\theta$. And
$f_\theta=0$ if $ x < 0$ or $ x>3\theta$</p>
<p>Let $\hat{\theta}=\overline{X}$ be an estimate for $\theta$ </p>
<p>I showed that $\... | g38997 | [
0.04044701159000397,
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0.027183204889297485,
0.007613984867930412,
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0.04668806493282318,
0.04686446860432625,
-0.014330594800412655,
0.... |
<p>I've just started building models in <strong>stan</strong>; to build familiarity with the tool, I'm working through some of the exercises in Bayesian Data Analysis (2nd ed.). The <a href="http://books.google.com/books?id=TNYhnkXQSjAC&pg=PA101&lpg=PA101&dq=bayesian%20data%20analysis%20waterbuck&source... | g62696 | [
0.01536477543413639,
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0.01017560251057148,
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-0.0483081117272377,
-0.06353896856307983,
-0.011332787573337555,
-0.010791429318487644,
0.03798430785536766,
0.... |
<p>I have the following data set and am trying to predict on the naive bayes values</p>
<pre><code>> head(dat)
lead_id email owns_home credit_type buyer_returned
1 12073402 b@hotmail.com 0 GOOD \\0
2 12073514 mo@cox.net 0 ... | g62697 | [
-0.004855037666857243,
0.0177695844322443,
0.008195750415325165,
-0.05194131284952164,
0.0019516617758199573,
-0.04561794549226761,
0.050826068967580795,
-0.08164115995168686,
-0.0703941211104393,
-0.07435957342386246,
-0.021972160786390305,
0.07368738949298859,
0.016949739307165146,
0.010... |
<p>Foreword : this is <strong>not</strong> homework, but a real problem : in a Bayesian model comparison context, I am trying to work out the correct prior density of mixed-model parameters which are, for computational reasons, computed as the centered and standardized means of other "raw" parameters, which are themsel... | g19890 | [
0.042108289897441864,
-0.05998029187321663,
0.0007050918065942824,
-0.018241997808218002,
-0.03324926272034645,
0.015348522923886776,
0.007684692740440369,
-0.019937533885240555,
-0.00973533559590578,
0.0007575862109661102,
-0.026238244026899338,
0.0029507980216294527,
0.026101119816303253,
... |
<p>I have a fairly simple dataset consisting of one independent variable, one dependent variable, and a categorical variable.
I have plenty of experience running frequentist tests like <code>aov()</code> and <code>lm()</code>, but I cannot figure out how to perform their bayesian equivalents in R. </p>
<p>I would lik... | g62698 | [
-0.009171951562166214,
-0.03199305385351181,
-0.022401858121156693,
-0.014745213091373444,
-0.007016977295279503,
-0.027396000921726227,
-0.012516398914158344,
0.004141611512750387,
-0.041414085775613785,
0.0010586853604763746,
0.014480287209153175,
0.025711823254823685,
-0.00146387948188930... |
<h2>The Question</h2>
<p>We have a sample of size $N$ with mean $\bar{x}$ and SD $\bar{\sigma_x}$ from a random variable $X \sim \mathcal{N} (\mu, \sigma^2)$</p>
<p>We have a sample of size $M$ with mean $\bar{y}$ and SD $\bar{\sigma_y}$ from a random variable $Y \sim \mathcal{N} (c\mu, c^2\sigma^2)$</p>
<p>We wish ... | g39008 | [
-0.0027925404720008373,
-0.007603162433952093,
-0.01710272766649723,
-0.021171627566218376,
-0.02753116749227047,
-0.03744591027498245,
0.01866048574447632,
-0.0176987387239933,
-0.038295015692710876,
-0.014448154717683792,
0.01674857921898365,
0.0028670900501310825,
0.0162527896463871,
0.... |
<p>My data is below.After taking differences 2 times,it looks stationary. Only lag 2 is significant in both pacf and acf plot.EACF says it is ARIMA(0,2,2) and I think it can be. However,if it is, aren't there supposed to be tailing off in PACF and significant both 1 and 2 lag. I put some plots and model fitting result ... | g62699 | [
0.038104332983493805,
-0.056701596826314926,
-0.0007573721813969314,
-0.06680124253034592,
0.08587834984064102,
-0.02257230505347252,
0.10924424231052399,
-0.04041672870516777,
-0.06672339886426926,
-0.007586537394672632,
0.0021016844548285007,
0.10061974078416824,
0.05201734974980354,
-0.... |
<p>Please pardon me for asking a simple question but I find this field rather very hard. Anyway, here it goes:</p>
<ol>
<li>We are trying to find MLE for a distribution. Now for a given distribution, its MLE is a number that is difficult to estimate. So what we do then is to use Sufficient Statistics for that particul... | g62700 | [
0.015353485010564327,
0.030501650646328926,
0.012648096308112144,
-0.08817212283611298,
-0.03639284148812294,
-0.024393612518906593,
-0.03230586647987366,
0.0580475851893425,
-0.032752327620983124,
-0.027634434401988983,
-0.01838117092847824,
0.0005772790755145252,
0.07198186218738556,
0.0... |
<p>I have two nested nonlinear models and I want to know which provides a better fit to some data. I see descriptions of both the likelihood ratio test and of the incremental F-test (also called the nested F-test or the extra sum-of-squares F-test) but I cannot find any discussion of when you would use one or the other... | g19893 | [
0.046472612768411636,
-0.026496192440390587,
0.009518377482891083,
0.04046196490526199,
-0.0049055153504014015,
-0.0327751524746418,
-0.01759621873497963,
0.030398955568671227,
0.003253154456615448,
-0.014246586710214615,
0.01753108762204647,
-0.0012276011984795332,
0.06057748198509216,
0.... |
<p>I want to estimate the parameters of the sum of two complex sinusoids embedded in Gaussian noise:</p>
<p>$y[n]=a_1 {\rm e}^{\,j n \theta_1} + a_2 {\rm e}^{\,j n \theta_2} + w[n]$</p>
<p>where $w[n]\sim {\cal N}(0,\sigma^2)$ and $n=1,\ldots,N$. Say that I want to compare the performance of different estimators (Pro... | g19894 | [
0.040794555097818375,
-0.08023981004953384,
-0.021479927003383636,
-0.03610610589385033,
0.004093956667929888,
-0.023194847628474236,
0.01484186016023159,
-0.01626349799335003,
-0.014271833933889866,
0.057742659002542496,
-0.048601824790239334,
0.03900645300745964,
0.03538675233721733,
0.0... |
<p>What are the best researched options for a parametric multivariate probability distribution that is able to be skewed, given curvature, and possibly even multiple modes? I have done some research into unified skew normal distributions and unified skew elliptical distributions, but the available research is very lean... | g62701 | [
-0.003922476898878813,
0.009065481834113598,
-0.008887115865945816,
-0.0034097626339644194,
-0.02711688168346882,
0.04416189715266228,
0.013162077404558659,
-0.008087903261184692,
0.00807296670973301,
0.016564173623919487,
0.0067600831389427185,
-0.03978744521737099,
0.06787169724702835,
-... |
<p>Is it possible to predict values of variables in a matrix Y from values of variables in a matrix X, ie. using canonical correlations since some variables are correlated among these two matrix?</p>
<p>X and Y contain variables for the same individuals.</p>
<p>If possible, I would like an example using R.</p>
<p>Ed... | g19895 | [
0.03642415627837181,
-0.060535456985235214,
0.003764452412724495,
-0.042172279208898544,
-0.0341220423579216,
-0.004487157799303532,
-0.012911733239889145,
-0.0032226908951997757,
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0.018335653468966484,
0.011784733273088932,
0.014110774733126163,
-0.022535592317581177,
... |
<p><img src="http://i.stack.imgur.com/wZwEX.png" alt="enter image description here"></p>
<p>I was plotting a deviation of my data points from a Gaussian smoothed curve depending on different properties of this Gaussian curve that smooths the series. </p>
<p>So I had a series of:</p>
<pre><code>y - result
g0 - value ... | g22478 | [
0.027121715247631073,
-0.034548304975032806,
-0.026404930278658867,
-0.053982242941856384,
-0.01336977444589138,
0.0035079708322882652,
0.0731833204627037,
-0.02037302777171135,
-0.015282904729247093,
-0.043885212391614914,
-0.011021886020898819,
0.04979977011680603,
0.09253281354904175,
-... |
<p>I'm newbie and bit lost... Can someone help me read this result from SPSS 1-sample Kolmogorov-Smirnov test (poisson distribution).</p>
<pre><code> SUBKEY1 SUBKEY2 SUBKEY3 SUBKEY4 SUBKEY5
N 128 128 128 128 128
Poisson ... | g4848 | [
-0.014077646657824516,
-0.054471392184495926,
-0.01964622735977173,
0.010071852244436741,
0.00966698955744505,
-0.000867095252033323,
0.011385658755898476,
0.05919025465846062,
0.0021855439990758896,
0.023949194699525833,
-0.016269497573375702,
0.03982663154602051,
0.032493021339178085,
0.... |
<p>I have samples of Bernoulli distributed variable that are neither the first nor the second i in iid. My goal is to model their sum. </p>
<p>I got from Wikipedia that I can use the poisson binomial distribution to make up for one of the i's, but then I have to keep all the inidividual probabilities.</p>
<p>It would... | g39015 | [
-0.003263952909037471,
-0.012324175797402859,
0.004931410774588585,
-0.0235602930188179,
-0.015607375651597977,
-0.015355084091424942,
-0.05488681420683861,
-0.002736845053732395,
-0.016066566109657288,
-0.022933006286621094,
-0.031775303184986115,
-0.019218875095248222,
-0.04222858697175979... |
<blockquote>
<p><strong>Possible Duplicate:</strong><br>
<a href="http://stats.stackexchange.com/questions/15197/how-to-interpret-the-divergence-of-fisher-information-expectation">How to interpret the divergence of Fisher information expectation?</a> </p>
</blockquote>
<p>Consider translated <a href="http://en.... | g49651 | [
0.020642219111323357,
0.027094952762126923,
-0.009532618336379528,
-0.03260628134012222,
0.041831400245428085,
-0.03979822248220444,
0.016168871894478798,
0.04915786162018776,
-0.038222528994083405,
-0.049941014498472214,
-0.06242210417985916,
-0.01918545365333557,
0.024656016379594803,
0.... |
<p>I'm trying to implement a Gibbs sampler, but I'm having trouble to find some of the conditionals of this model.</p>
<h2>Model</h2>
<p>We have $A$ actors, $K$ classes or clusters, and a matrix $\phi$ that determines the probabilities of two classes interacting. </p>
<p>The generative process would be like the fol... | g62702 | [
-0.011457232758402824,
-0.006829829886555672,
-0.0097386185079813,
-0.01668599620461464,
0.04293698072433472,
-0.03657134622335434,
0.058617521077394485,
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-0.004291926976293325,
-0.02962646633386612,
-0.006266482640057802,
0.027406740933656693,
0.017758747562766075,
0... |
<p>I've been trying to create a multivariate regression model to fit my training data into the prediction of a value. I've put my data into a matrix <code>X</code> with <code>m x n</code> where <code>m</code> is the number of instances and <code>n</code> the number of features/predictors. My label vector is then <code... | g62703 | [
-0.003475487930700183,
0.008298472501337528,
0.00008113073272397742,
-0.050894059240818024,
0.01799452118575573,
-0.03945792838931084,
0.06283042579889297,
0.03342277929186821,
-0.04344542697072029,
-0.013596178963780403,
-0.014593319036066532,
0.011859577149152756,
0.027652151882648468,
0... |
<p>Here's the problem:</p>
<p>A (Laplace) coin with sides $0$ and $1$ is tossed twice, each time independently from the other. Let</p>
<p>$f:=$ maximum of both results</p>
<p>$g:=$ sum of both results.</p>
<p>What is the expected value and variance of $f$ and $g$?</p>
<p>I think $E[g]=2*\frac{1}{4} + 1*\frac{1}{2}... | g19903 | [
-0.0010407393565401435,
0.0284261517226696,
-0.011781387962400913,
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0.04287467524409294,
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0.021764881908893585,
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-0.01512336079031229,
-0.07459986209869385,
0.07106643915176392,
0.01192380115389824,
-0.01... |
<p>Let $\mathbb{M}$ be an $m\times n$ matrix, with $m < n$.
My data consists of a large list of points $\mathbf{x}_i\in\mathbb{R}^n$, $i=1,...,N$, where each point satisfies $\mathbb{M}\cdot\mathbf{x}_i = 0$ and $\mathbf{A} < \mathbf{x} < \mathbf{B}$, where vector inequality denotes all component-wise inequali... | g4872 | [
-0.007967106066644192,
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-0.018814174458384514,
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0.010900833643972874,
-0.003401803318411112,
0.030572570860385895,
0.0022107705008238554,
0.04011714458465576,
-0.03760860860347748,... |
<p>In a questionnaire I conducted for my dissertation, i asked respondents to rate the frequency (5 point scale from never to always) to which they resorted to certain unethical behaviour during their work. I also asked them to rate their acceptance of such behaviour using a reliable scale (5 point scale from Strongly ... | g62704 | [
0.02785821445286274,
0.04546237364411354,
0.01726887747645378,
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0.004231106024235487,
0.014423280954360962,
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0.029061246663331985,
0.03627314418554306,
0.0384456142783165,
0.010599509812891483,
-0.01866143010556698,
0.05947... |
<p>I admit that my algebra is rusty. Can someone please explain how the middle part of the top equation is transformed to the middle part of the bottom equation (both are highlighted in black).</p>
<p><img src="http://imgur.com/DqgVr26.jpg" alt="equation"></p> | g62705 | [
0.011233043856918812,
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0.005696972832083702,
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0.0492979921400547,
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0.013407542370259762,
0.0328248105943203,
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0.08106241375207901,
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-0... |
<p>I have been searching for the answer for a problem with confidence intervals for a long time now, so I hope someone can help!</p>
<p>The two psychological papers below performed the same analysis, regressing irregular word reading onto nonword reading for controls, and plotting these regressions with 90% confidence... | g62706 | [
-0.0026391400024294853,
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0.02957290969789028,
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0.0489555187523365,
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0.026116590946912766,
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0.01708758808672428,
-0... |
<p>I have (censored) time-to event data for subjects in four groups. I would like to do something like a logrank test, but the survival curves do not satisfy the proportional hazards assumption. I think I have heard that the consequence of a prop. hazards violation is loss of power to identify differences between sur... | g39024 | [
0.019129358232021332,
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0.005155688617378473,
-0.01645568013191223,
0.022501904517412186,
0.0026262940373271704,
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-0.006585820112377405,
0.03807862102985382,
-0.023926004767417908,
0.0799555554986,
0.008... |
<p>I am trying to dummy code a variable sector which have 20 levels. I am trying to combine some of levels. However I got this situation, if I have a say 2000 observations, how do I decide on the minimum frequency of a particular level that I should consider before making it a dummy variable, as variable with low frequ... | g62707 | [
0.023786636069417,
0.005126736592501402,
-0.0008392895688302815,
-0.05786510184407234,
0.03942067176103592,
-0.011255391873419285,
0.025986485183238983,
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-0.06330803036689758,
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0.004483399447053671,
0.0025300399865955114,
0... |
<p>Is any one here familiar with an R package called Zelig?</p>
<p>I have a data frame like this:</p>
<pre><code>IQ AGE
80 50
100 18
90 25
</code></pre>
<p>etc.</p>
<p>What I need to do is build a model of IQ given AGE, I am running these commands:
<code>z.out <- zelig(IQ~AGE,data=df,model="ls")</code>
th... | g62708 | [
0.008814948610961437,
-0.0282549150288105,
-0.01511007733643055,
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0.007084726821631193,
-0.024228159338235855,
0.051075611263513565,
0.011137261986732483,
-0.028284339234232903,
0.008158102631568909,
-0.04739119112491608,
0.03400168940424919,
0.03822802007198334,
0.00... |
<p>In <a href="http://rads.stackoverflow.com/amzn/click/158488388X" rel="nofollow">Gelman's Bayesian Data Analysis</a>:</p>
<blockquote>
<p>The t distribution is <strong>the marginal posterior distribution for the normal mean with unknown variance</strong> and <strong>conjugate prior distribution</strong> and can be... | g62709 | [
0.07031900435686111,
0.0037860439624637365,
-0.00452561816200614,
-0.0804537758231163,
-0.08000748604536057,
0.02386253885924816,
0.011746218428015709,
0.0420406237244606,
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-0.06325509399175644,
0.006200097035616636,
0.01604757271707058,
0.009508024901151657,
-0.02312... |
<p>I am a beginner in Machine Learning. For my project I need a regression algorithm that can estimate the 3D position of a device based on some constraints (moreover inputs). I know how to implement regression algorithms (using gradient descent) for scalar outputs. But in this case the output is a position vector. Can... | g10214 | [
0.014535868540406227,
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-0.011320570483803749,
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0.022790616378188133,
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0.06435436755418777,
0.05639711022377014,
0.0... |
<p>In survival analysis, what is the difference between time-varying coefficients and time-varying variables? Suppose we have the following Cox-Proportional Hazards Model:</p>
<p>$$\log[h(t)] = \log[h_{0}(t)]+ \beta_{1}x_1(t)$$</p>
<p>vs</p>
<p>$$\log[h(t)] = \log[h_{0}(t)]+ \beta_{1}(t)x_1$$</p>
<p>In the first mo... | g62710 | [
-0.009195048362016678,
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0.005237014964222908,
0.006907986011356115,
0.0924140065908432,
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0.03135179728269577,
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0.033570364117622375,
0.0664391815662384,
-0.013... |
<p>I've been working with JMP, and I have found that often I get a significant p value but a relatively small r. Is this supposed to happen?</p> | g28454 | [
0.04751517251133919,
-0.003038774011656642,
0.0048194387927651405,
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-0.008318335749208927,
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-0.042462874203920364,
-0.012266311794519424,
0.005650985054671764,
-0.008238574489951134,
... |
<p>What's the formula for a equation that can produce the continuum from the red to green lines in this graph below? I can easily get anywhere from the green line to the blue with $$y = B_0 + B_1x + B_2x^3$$ but getting anywhere from the blue line to the red line requires an inverse of the cube or x^(1/3) which doesn't... | g62711 | [
-0.008263909257948399,
-0.0008100880077108741,
-0.008370957337319851,
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0.0031081836204975843,
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-0.03592009097337723,
0.019157325848937035,
0.058428846299648285,
0.05032947286963463,
... |
<p>My dataset is not quite large enough to be split into training and testing sets, so I am using bootstrapped optimism to account for overfitting when reporting model performance.</p>
<p>The cases in my data set have a low prevalence, such that in some iterations of sampling they're missed. To account for this I've i... | g62712 | [
0.0009004600578919053,
-0.03150637075304985,
0.001872614142484963,
-0.02542916126549244,
-0.008064772933721542,
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0.019845666363835335,
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0.0063025434501469135,
0.06811442971229553,
-0.005538884084671736,
0.03067891299724579,
0... |
<p>I am <a href="http://stats.stackexchange.com/questions/92481/algorithm-for-scoring-co-varying-traits">trying again</a> to explain my problem, and I have more concrete results. I have tried every potentially relevant test I can find, and none seem to work quite right.</p>
<p>The question is illustrated here:</p>
<p... | g62713 | [
0.03788585588335991,
-0.011786006391048431,
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0.014012353494763374,
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0.010432381182909012,
0.04089094325900078,
0.0049845557659864426,
0.026676947250962257,
-0.0278... |
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