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Partitioning variance from logistic regression

Short version How can I partition the variance from the different levels in a nested mixed-effects logistic regression? Preferably using R, but even general principles would be helpful as a start. ...
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is it possible to use partitioned data(train&test) together with cross-fold validation?

I have used SPSS Clementine in order to train a classifier, for this I have used a partition node with 2 parts(train and test),then using a c5-tree and cross-fold validation. I did this because I ...
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69 views

R procedure for comparing multiple categorical variables (similar to anova() followed by t.test() for continuous)?

Big Picture: How can I implement partitioned Chi Square in R? I understand how to perform the overall Chi square, and then how to get individual parameters (observed counts, expected counts, ...
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20 views

Neural Net on results from Partition Bootstrap Forest - validity?

I am seeing some promising results with this method for my 'nutrition' dataset but am wary about modelling on results of a model. Problenms with this data I cannot seem to reduce my many correlated ...
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2answers
75 views

Does Newman's network modularity work for signed, weighted graphs?

The modularity of a graph is defined on its Wikipedia page. In a different post, somebody explained that modularity can easily be computed (and maximized) for weighted networks because the adjacency ...
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27 views

Investigating 'minor' effect variables?

Is there any way to investigate minor contributing $X$ variables in a model when there are one or two $X$ variables which contribute to the explanation of a majority of the variation in the $Y$ ...
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2answers
45 views

Class labels in data partitions

Suppose that one partitions the data to training/validation/test sets for further application of some classification algorithm, and it happens that training set doesn't contain all class labels that ...
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1answer
83 views

How interactions between explanatory variables can be found using binary recursive partitioning?

I would like to investigate interactions between my explanatory variables prior to building a statsitical model. Apparently it is possible to do it in R using a regression tree (library: tree). This ...
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1answer
64 views

Modularity of graph: why are probabilities of self-loop included?

I'm trying to understand the Newman Modularity (doi:10.1073/pnas.0601602103) by investigating its calculation on the Wikipedia example . My question is why are probabilities of self-loops included in ...
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15 views

Most similar combination of partitions to the rest of group

I have a number of sample sequences of data that I want to compare with another large number of sequences of data. These samples are partitioned in between and I want to see which combination of ...
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91 views

Variance partitioning - why be cautious?

I'm about to use variance partitioning to interpret my results of a given model and across models and have come across various criticisms of it most notably by Pedhazur (1982, 1997). Also, the ...
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1answer
225 views

Partitioning Around Medoids

I have a question regarding Partitioning Around Medoids (PAM) clustering algorithm, because everywhere I look, it is described differently. In every step of the algorithms do I swap only one medoid or ...
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30 views

Partitioning $R^2$ in a Network-Disturbance auto-correlation model

I am currently running a disturbance model that will allow me to adjust for Galton's problem in cross cultural data in the form of: $y = x\beta + \epsilon, \epsilon = \rho_1 W_1 \epsilon + \rho_2 W_2 ...
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25 views

Testing that a finite quantity is equally partitioned

Suppose I have a set of observations on a finite (continuously divisible) quantity $Q$ (say $Q = 100$ to be concrete). For each observation $i$, $Q$ is partitioned into three parts $(A_i, B_i, C_i)$, ...
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39 views

Discretization of skewed data (time durations)

I have data that describes the duration of how long a person views a webpage. This is quite varied and in the context wherein I gathered the data, it was very skewed. People mostly spent short amounts ...
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1answer
78 views

Multivariate Gaussian with 3 Partitions

Given that we partition a Gaussian random vector $\textbf{x}$ into three groups, $\textbf{x}_a$, $\textbf{x}_b$, and $\textbf{x}_c$, with a corresponding partitioning of the mean vector $\mu$ and of ...
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2answers
93 views

Linear SVM C optimisation data, how to partition into train, model construction, test

My aim is to find the best C for a linear SVM classification using libsvm, I have 120 instances in total and 2 classes which I want to classify. I have question regarding partitioning a the dataset ...
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1answer
130 views

Is $R^2$ value valid for insignificant OLS regression model?

I am interested in stating that ___ % of the variance in Y is explained uniquely by $X_1$ and ___ % is explained uniquely by $X_2$. Is there some way to obtain this from a multiple regression ...
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59 views

How to Partition An Interaction SS in ANOVA

I'm a new user of R and I'm trying to replicate Table 6.18 on page 262 in Statistical Procedures in Agricultural Research, By K. A. Gomez and A. A. Gomez. New York, Chichester, etc.: Wiley (1984). ...
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1answer
137 views

Can I partition a frequency table and use Fisher's exact test instead of the chi-squared test?

I am working with very small cell counts, and am wondering if Fisher's exact test can be used in place of the chi-squared test when partitioning IxJ tables. I am interested if the same process for ...
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1answer
299 views

mobForest R Package

I have recently begĂșn to learn about model based recursive partitioning by playing around with MOB in the party package. I came across this mobForest package but am a little baffled towards what it is ...
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2answers
187 views

Statistical independence of combining random samples

Given a single finite population of size N, if I obtain S random samples from the data (replacing after each one), and randomly partition these into 2 sets of S/2 random samples, can I treat these two ...
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1answer
202 views

Bootstrap confidence intervals for partitioned variances in R

I'm trying to determine the variance partitioning within plant drought tolerance data among hierarchical ecological levels, from species to forest sites to biome levels. I did that with the varcomp ...
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2answers
1k views

How do I find similarities between two sets of data

I have a group of data with 12 different football players, and they are rated for 11 different skills (speed, skill, flair, etc). I am looking to pair up individuals based on similar footballers, and ...
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1answer
210 views

Is there a statistically good way to split a set of data into (generally) uneven groups?

So here's the scenario: I have about 100 or so "items", each assigned with a number and total guesses... this number is a guess of what people think the item is worth (in terms of money). This number ...
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1answer
78 views

Can complex sampling be ignored for exploratory patient-centered analyses?

Hello fellow StackExchange users, Preamble: I have been tasked with performing a cluster analysis (or possibly a latent class analysis, as I am pondering) to find non-overlapping groups of like ...
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1answer
195 views

Number of events of type B given n events of type A in a Poisson process

I have a simple probability calculation I was working on that I came up with an answer for, but a question a colleague asked me led me to come up with a second approach - and a different answer. I put ...
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2answers
180 views

Problem of “clustering” into most similar groups

I do not think that the following problem can be solved with k-means clustering. I am not sure though. Okay, let me describe the problem. I need to find a way or an algorithm that groups members of a ...
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1answer
89 views

Where can I find the articles discussing about the suggested training-data partitioning ratio?

Right now, I'm doing my thesis which use multilayer perceptron learning method to train a model. What I learned from my class is the purpose to partition the data which can be separated into 3 group ...
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1answer
1k views

How to use the hier.part package for hierarchical partitioning?

Hello after struggling with using R for the last couple of days I was hoping someone could help me with a statistical analysis I am completing for an environmental science honours project. Using R ...
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1answer
254 views

Estimate the population variance from a set of means

I have a set of measurements which is partitioned into M partitions. However, I only have the partition sizes $N_i$ and the means $\bar{x}_i$ from each partition. Because all measurements are assumed ...
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2answers
2k views

party vs. rpart vs. ??? for partitioning trees in R

It's been a while since I looked at partitioning trees. Last time I did this sort of thing, I like party in R (created by Hothorn). The idea of conditional inference via sampling makes sense to me. ...
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1answer
194 views

Stationary distribution on a partition of the state space?

I would like to use the following type of model and am wondering if someone could let me know if this technique has been studied before (I assume it has) and where to learn more about it? The idea is ...
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145 views

Establishing a dynamic threshold for partitioning data

Given a sorted set of data points, where each point represents the length of a common substring between two files, I want to systematically decide a cut off point where I can start considering them to ...
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1answer
579 views

Difference in implementation of binary splits in decision trees

I am curious about the practical implementation of a binary split in a decision tree - as it relates to levels of a categorical predictor $X{j}$. Specifically, I often will utilize some sort of ...
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1answer
105 views

calculate the rate of change

I posted this on maths, but seems it would be better here :S http://math.stackexchange.com/questions/49941/calculate-the-rate-of-change Basically I am trying to calculate the change frequency for ...
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1answer
1k views

Interpreting output of igraph's fastgreedy.community clustering method

With the help of several people in this community I have been wetting my feet in clustering some social network data using igraph's implementation of modularity-based clustering. I am having some ...
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7answers
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How to do community detection in a weighted social network/graph?

I'm wondering if someone could suggest what are good starting points when it comes to performing community detection/graph partitioning/clustering on a graph that has weighted, undirected edges. The ...
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2answers
1k views

Newman's modularity clustering for graphs

I am interested in running Newman's modularity clustering algorithm on a large graph. If you can point me to a library (or R package, etc) that implements it I would be most grateful. best ~lara