# All Questions

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### Scikit-learn Normalization mood (L1 vs L2 & Max)

I was wondering if anyone here can explain the difference between the l1, l2 and max normalization mood in sklearn.preprocessing.normalize() module? Having read the documentation I couldn't realize ...
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### Maximum entropy distribution of a proportion with known mean and variance? Is it a beta?

Given a proportion and its standard error, what distributional assumption minimizes assumptions/maximizes entropy? Is it the beta (and can I use the method of moments to estimate its parameters)? Or ...
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### Paired T-Test or ANOVA or Neither

So I ran an experimental study between an intervention group and a control group who all got assigned a participant number. I tested at 3 time periods, pre, post & follow up. I was going to test ...
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### Line flatness metric

I'm building an automated trading system and need to develop a line flatness metric (measure). One way of doing it I though of is taking the first and last points in the dataset, 'drawing' a line ...
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### How to normalize data to 0-9 range?

I have two data sets that track the same information using two different scales. The first scales values in the range 0-5 and the second scales values 0-9. I know that the following formula will ...
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### 40,000 neuroscience papers might be wrong

I saw this article in the Economist about a seemingly-devastating paper casting doubt on "something like 40,000 published [fMRI] studies." The error, they say, is because of "erroneous statistical ...
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### How do we know that the probability of rolling 1 and 2 is 1/18?

Since my first probability classes I have been wondering about the following: Calculating probabilities is usually being introduced via the ratio of the "favored events" to the total possible events. ...
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### Significant interaction but simple slopes non-significant [on hold]

I have looked at the boards and have yet to find a clear answer to this question. What does it mean when there is a significant interaction but the simple slopes are non-significant besides that they ...
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### Should I optimize neural networks that are part of ensemble of neural networks?

I'm creating ensemble of neural networks for a simple binary classification task. Every neural network is generated and trained a bit differently (number of hidden layers, number of neurons per layer, ...
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### Prisma App Neural Networks

Can anyone point me towards relevant material that would allow me to understand how Prisma works? http://prisma-ai.com/index.html
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### pyJAGS vs RJAGS

I was wondering if there is any empirical studies out there to compare performance of different JAGS bindings, specifically RJAGS and pyJAGS. I am mainly interested in speed. Currently I have an ...
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### Simulating an overdispersed negative binomial distribution

I have RNAseq data in the form of normalized counts. The counts themselves follow an over-dispersed negative binomial, and I would like to generate random data which replicate these distributions. For ...
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I have drawing data from 10 subjects drawing 8 shapes (and many repetitions of every shape). I fitted a model to this data Matlab, separately for each subject and each shapes, such that I have 2 model-...
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### Scaling breaks for ggplot [on hold]

I have a code: base=plotTsTile(JJ7, plot.title = 'J1', legend.title ='CHLAT', four = TRUE) From the R package wq, their breaks are by decades. I only have 20 years, so 5 year breaks and 10 year ...
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### Tune parameters from a specific equation in R

This is the first time I am truing to tune model parameters in R. I have a fairly complicated equation with multiple parameters: ...
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### Run regression where dependent variable Y is always constant and independent variable X is not constnat [on hold]

I have a situation where Dependent variable is GDP and that is constant. on the other hand there is one Independent Variable and other dummy variables and they are not constant.I have tried many ...
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### Test Support Vector Machine on its own Training Data: issues and observations

I recently concerned myself with SVMs and Sparse Bayesian Machines (RVMs) and was performing feature scaling of my highly skewed data prior to the training of my algorithm. When I was subsequently ...
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### KNN on collaborative filtering

After I calculated the similarities matrix, how do I get the neighbors? For example, consider the matrix of similarities between users, if I did not make any mistakes, the matrix must be symmetric ...
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### How to estimate “partial” attribute profile choice model?

How does one estimate a choice model (McFadden MNL) on a design where there is a set of fixed attributes and a set of "variable" attributes that cycle in and out of choice sets? I believe this is ...
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### Extracting X-13ARIMA forecasts of seasonal effects [migrated]

I am attempting to forecast seasonal effects in various consumer price index components (foods, services, goods, etc.). In other words, I am interested in obtaining - for each time series - forecasts ...
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### Family of flexible parametric mappings $f_\theta:(0,1) \rightarrow \mathbb{R}$?

For the purpose of reparameterizing a model (mostly with the goal of improving MCMC efficiency), I am looking for a family of flexible parametric mappings $f_\theta:(0,1) \rightarrow \mathbb{R}$ such ...
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### Distribution of Likelihood Values for Simulated Data

Say I have a model with certain parameters and generate a number of simulated data sets from it. If I was to maximise the likelihood function for each data set, how would that distribution of ...
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### Probability of finding a new smallest value

I am doing some simulations and I need a good heuristic for when to stop the simulation. The simulation continuously outputs data with a cost in the range [0,1]. ...
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### How to evaluate an open-set classification scenario?

We're given an open-set classification scenario, where we have a test set with known classes: $K = \{A_1, A_2, \ldots, A_m\}$ and another (open) test set $U$ with unknown classes than can be almost ...
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### Two-way ANOVA unbalanced design: no matching results between R and GraphPad Prism

I'm getting some troubles in comparing results from ANOVA performed with Rstudio and ANOVA from the software GraphPad Prism. They don't match each other despite the same dataset. I have an ...
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### Varying outputs for the same train and test data

I have the below sample code in which I am using the sklearn(scikit-learn=0.16.1) 20newsgroup dataset: ...
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### Forecasting Incident ticket trend based on past data [on hold]

I'm trying to develop a prediction model the on Incident Ticket logged for my support queue for next 3 months, based on past 12 months data (trend). We need to consider the cause of creation of ...
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### Comparing the intervals between population means

First of all, I have to admit that my stats training is somewhat basic, but I'm very willing to look into things, as I really enjoy working with stats. I am working with a household survey which ...
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### Plot data points that has up to 20 dimension using t-SNE tool [on hold]

follow my data set , i would like to plot this data set using t-SNE tool, i have follow exactly the instructions by submit a spreadsheet, but its not draw my points and just view white image , i have ...
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### Moderation in Generalized Linear Model

I have conducted an experiment with a control group and two experimental groups (each with a different N). The respondents in the three groups were all exposed to same donation situation. Each of the ...
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### How to generate realistic random numbers given mean, max and minimum? [on hold]

My problem is that I am simulating an application scheduling tool but ofcourse I need to validate it with the real thing. In the real tool, all tasks will take some time to execute that is determined ...
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### Clustering large graphs - random submatrix SVD. Is it still state of the art?

I am interested in the problem of clustering graphs/datasets with 10s of millions or more feature vectors. I was therefore very interested in this very highly cited paper from 2004 "Clustering ...
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### use corrected or uncorrected variance when calculating skewness & kurtosis?

In several online sources, e.g. NIST engineering statistics handbook I have read that for the calculation of skewness & kurtosis I should use N in the denominator instead of (N-1) when calculating ...
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### adjusted residual is above 1.96, but the confidence interval goes through 1?

I am analysing whether patients ethnicity affects uptake of the influenza vaccination. I have undertaken chi square test on a 6x2 table (6 categories of ethnicity against accepted/declined vaccination)...
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### Publication bias: which test should I use and what are the formula

I am working on the last part of my meta-analysis. I am using a random-effects model. I am looking at uncontrolled effect sizes (difference between pre-test and post-test scores using Cohen's d). I ...
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### Running many multiple regressions at once in R

I want to run time series regressions (Fama-French three factor with my new factor). I have following tables. ...
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### Average duplicates before fitting?

Common practice for calibration curves is to take several duplicate measurements for each timepoint (or concentration, whatever variable) and fit using the average of each measurement set. The ...
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### Discrete probability distribution with two 'tails'

I am interested in knowing whether there is any discrete probability distribution similar to Poisson but also extended in the negative value part (i.e., it can take negative values and there is no a ...