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Open-sourced pairwise learning models

I am solving a classification problem using pairwise-learning training set. We have 2 classes: bad and good. We also have pairs of objects $(a_i,b_i)_{i=1}^n$, meaning that object $a_i$ is better than ...
1k views

Out of sample predictions for logistic regression models in R

I have a problem of the form "what is the probability that a user will 'like' a certain movie?" For a bunch of users, I know the movies each has watched historically, and the movies each has liked. ...
1k views

Seasonally adjusted month-to-month growth with underlying weekly seasonality

As a side hobby, I have been exploring forecasting time series (in particular, using R). For my data, I have the number of visits per day, for every day going back almost 4 years. In this data there ...
2k views

How to find best split in decision trees using label vectors?

In single label learning, we have a single label that we need to predict. Most training tasks are single label, like the most common example where we need to predict if a customer is going to be good ...
3k views

Cross validation and ordinal logistic regression

I am trying to understand cross-validation for ordinal logistic regression. The aim of the game is to validate the model used in an analysis... I first construct a toy data set: ...
7k views

How do I improve my neural network stability?

I'm using the neuralnet in R to build a NN with 14 inputs and one output. I build/train the network several times using the same input training data and the same network architecture/settings. ...
26k views

How to perform post-hoc comparison on interaction term with mixed-effects model?

I’m working on a data set in order to evaluate the impact of drying on sediment microbial activities. The objective is to determine if the impact of drying varies among sediment types and/or depth ...
2k views

Convex vs. concave curve - measurement or index

I am interested in a measurement or index that will tell me if a curve is more convex or concave versus a straight line. This curve is sampled in n points and I know the x and y coordinates of these ...
216 views

Intersubject concordance for ratings vs rankings

In my system I ask $n$ people to rate [1,5] $m$ objects (e.g. films). I'd like to get a measure of the inter-subject concordance, i.e. how much the users agreed overall, not just on a particular ...
410 views

learn R (Statistics) [closed]

I'm considering using R for my master thesis in order to do some analyses with the mvpart package. The problem is that I only have limited time to learn the program and to do the analyses. I already ...
470 views

Number of states and symbols in multi class Hidden Markov Model classifier

I'm designing a multi class classifier (for 4 classes) using Discrete HMMs with States N and Symbols M for each of the HMM. However, I found that recognition performance(i.e highest log likelihood) ...
891 views

Network graph with avatars as nodes

I've got a problem. I need to create network graph where avatars are nodes (different sizes). Similar to this one: Furthermore on this image every avatar has the same size, what I need to do is ...
5k views

What is the most accurate way of determining an object's color?

I have written a computer program that can detect coins in a static image (.jpeg, .png, etc.) using some standard techniques for computer vision (Gaussian Blur, thresholding, Hough-Transform etc.). ...
4k views

Cohen's d for 2x2 interaction

I have a significant 2x2 interaction in a between-subjects design. I would normally report omega-squared as my effect-size measure, but I've been asked to provide Cohen's d instead? Can Cohen's d be ...
1k views

Train NN or SVM to classify stock signals

I am applying Neural network and SVM to predict buy-hold - sell signals. I have trained nn and SVM in R. I used nnet function to train NN and svm to train SVM. I provided 20,000 data points to train ...
345 views

Measuring inter-subject agreement in user ratings

In my system I have users rating objects (e.g. films) from 1 to 5 stars. The mean rating clearly tells something about the overall opinion on an object, but I'd like to use a more precise measure of ...
237 views

Posterior mean of exponential functions: how to do it with MCMC?

I am struggling with estimation of posterior mean of simple exponential function f(x)=exp(x). Mixing of the chain is quite good and there is no problem with estimation of simple mean, but since ...
2k views

Incremental training of Neural Networks

Is it valid to train a neural network over and over again with new arriving data (including pruning after each new training)? I plan to collect data for a period of time, train/cv/test the networ, ...
438 views

Find a mapping of two probability mass function to another probability mass function

Lets' $p$ and $q$ are probability mass functions of two discrete random variables. I need examples of functions $F(p,q)$ that $r = F(p,q)$ and $r$ is a probability mass function for some random ...
897 views

27k views

When to use Fisher and Neyman-Pearson framework?

I've been reading a lot lately about the differences between Fisher's method of hypothesis testing and the Neyman-Pearson school of thought. My question is, ignoring philosophical objections for a ...
320 views

Large performance variance when using back-propagation in neural networks for feature extraction

I'm using a multi-layered neural network for feature extraction (similar to deep belief network). I test the performance of my model with cross-validation. When I'm using back-propagation to train ...
2k views

How are piecewise cubic spline bases constructed?

There are words from the The Elements of Statistical Learning on page 119: It is not hard to show that the following basis represents a cubic spline with knots at $\xi_1$ and $\xi_2$: \$h_1(X)=...
3k views

Adjusting data for age and bmi

I am doing a study on the effects of bad blood sugar control on patients. BMI, age, type of diabetes (Type 1 and 2 or gestational diabetes) are all variables. Outcomes include C section, early labour ...