0
votes
0answers
5 views

Sample size in the Latin Hypercube simulation to calculate P90, average and P10 and number of variables relation

I am preparing some simulations to determine the P90, average and P10 of a parameter. How many runs do I need to have to get a reliable answer (let's say 5% margin of error and 95% confidence)? It ...
-1
votes
0answers
13 views

Sample Mean and Sample Standard Deviation [on hold]

How do I calculate sample mean from the question like below: A company has following samples of leaking goods with gaps 0.290, 0.104, 0.207, 0.145, 0.104,0.124. I couldn't understand the question ...
1
vote
0answers
9 views

Recaculating control limits when an out of control situation is displayed

When plotting control charts if a point plots outside the control limits then the reason for that point to plot outside is checked and if an assignable cause is found to be the cause then after ...
2
votes
2answers
23 views

Imputing using CFA for use in a Cox regression

I am using CFA (confirmatory factor analysis) to create a measurement model of social capital that is to be used in a Cox regression. Because of missing data I first impute the incomplete data by MICE ...
-1
votes
0answers
10 views

Moderating a curve [on hold]

I have a paper that has a main relationship with a negative curve. It actually looks like a left leaning hockey stick. We have three moderators - two that strengthen the negative slope and one that ...
0
votes
0answers
7 views

How to test composite hypothesis for the linear regression model

I want to test $H_0:\beta_1>0,\beta_2=\beta_3=0$ in the model $Y = \beta_1x_1 +\beta_2x_2 + \beta_3x_3+\epsilon$. How can I do this?
0
votes
1answer
15 views

Grid search error in LIBSVM while optimizing C and g parameters

I am using libsvm for a one-class classification problem. I am trying to select the ideal C and gamma parameters for different kernels(polynomial, linear and rbf) I am using the suggested matlab code ...
2
votes
2answers
44 views

What coefficients do I use for a binomial distribution problem?

I'm studying for an exam and my study guide explained combinations, permutations, and binomial distributions, but didn't cover much how to recognize where each comes into play in problems. I'm having ...
0
votes
1answer
22 views

What are the various basic kernels available?

I am currently following the book Gaussian Processes for Machine Learning by C.E. Rasmussen and C.K.I. Williams and I have come across various kernels in their Chapter 4 I have also gone through the ...
0
votes
0answers
23 views

Why does NSDIFFS (R forecast package) never show seasonality? [migrated]

I've been using the EViews statconn DCOM interface to loop a large number of series from FRED through the nsdiffs(test=c("ch")) function in the forecast package of R to examine what percent of them ...
2
votes
2answers
36 views

What are the parameters of a Wishart-Wishart posterior?

When infering the precision matrix $\boldsymbol{\Lambda}$ of a normal distribution used to generate $N$ D-dimensional vectors $\mathbf{x_1},..,\mathbf{x_N}$ \begin{align} \mathbf{x_i} &\sim ...
0
votes
1answer
29 views

Is high AIC a bad feature of the model?

I have a model with AIC equal to 78 809. Does this mean this is a very bad model or the intepretation should be different? There are 15 variables, 2-level response variable and 40 000 rows. ...
4
votes
1answer
27 views

Simulating a data generating process

Suppose I wanted to simulate the data generating process of a non-linear regression with ma(1) errors. So, without going into many unnecessary details, the model is $$y_t = f(x_t,x_t-1,..., x_{t_0}, ...
3
votes
1answer
109 views

Linear independence vs statistical independence (PCA and ICA)

I'm reading this interesting paper on application of ICA to gene expression data. The authors write: [T]here is no requirement for PCA components to be statistically independent. That is true, ...
0
votes
1answer
30 views

How to standardize text data for training Neural Networks?

I want to train neural network with text data(natural language) as input for classification purpose. One way for standardizing text data for neural network is to use N-GRAM/SKIP-GRAM representation ...
0
votes
0answers
7 views

How to plot ROC curve after using SMO classifier in weka? [on hold]

I classified my data using SMO function in weka. The ROC plot that I got is not a curve (it is based on just one threshold). can anyone help me to plot ROC curve for more decision threshold? how can ...
1
vote
0answers
23 views

2 factor factorial model with random factors

Using lme4, how does one define a full 2-factor factorial model with both factors (and their interaction) being random? Specifically I am trying to recreate the ...
0
votes
0answers
11 views

Regarding post pruning in decision tree

Just 2 issues: 1) what should we do say for example we get 5 Yes and 2 No for a single final leaf node attribute? 2) How to post prune using Chi square test?
0
votes
0answers
11 views

Multi-signal coherence test

Is there an accepted measure for multi-signal coherence? The signals are time-domain EEG voltage readings from various parts of the scalp. I was working with magnitude-squared coherence, but it only ...
0
votes
0answers
6 views

Anyone knows how to make a LSTM layer that is able to be trained with arbitrary BPTT time steps and easy to be stacked together?

Anyone knows how to make a LSTM layer that is able to be trained with arbitrary BPTT time steps and easy to be stacked together? I am now implementing a basic version of LSTM layer. My scan function ...
0
votes
0answers
19 views

How can we compute cumulative change rates for time series data? [on hold]

Take the annual precipitation data for some area from 1960 to 2008 as an example. How can we compute cumulative change rates for such data?
0
votes
1answer
33 views

Is there a correlation index for Binary Variable vs Quantitative variable?

I know that I can use a logistic regression model to test if quantitative variables influence the binary variable, but I would like to have an Index, like Pearson correlation index to tell how strong ...
1
vote
2answers
43 views

Product of two gaussian processes

Given, $\ {y}_{i} = N({\mu}_{i}, {\Sigma }_{i}) $ If we go by the link http://www.tina-vision.net/docs/memos/2003-003.pdf then we can understand that the product of many multivariate gaussians can ...
0
votes
0answers
6 views

Is there a general structure for papers/documents explaining computer vision databases?

I recently created a database of images for testing a specific computer vision problem. Due to lack of data in the first place, I designed an algorithm which generates new images from the few existing ...
0
votes
0answers
10 views

Applicability of Hilbert-Huang Transform for linear trend analysis

I have a question about the applicability of the Hilbert-Huang Transform / empirical mode decomposition (HHT/EMD). Suppose I have a time series dataset in which there is probably an N-year periodic ...
1
vote
1answer
23 views

Rearrange regression equation that includes a dummy variable

This is my regression equation: $10 = 5.44 + 0.26X_1 - 3.19X_2$ $X_2$ is a dummy predictor with two levels. Assume that the value of $X_2$ is 1 therefore regression equation is: $10 = 5.44 + ...
0
votes
0answers
7 views

Poisson glm overdispersion. Calculating QAICc for model comparison

I'm having some difficulties with my glm . The models are overdispersed so I want to run them as quasipoisson. I would like to be able to compare the models using QAICc but the packages I have ...
-1
votes
0answers
28 views

How to predict/find a value based on historical data using statistics? [on hold]

I am not aware about statistics but want to implement statistical concepts. Following is scenario. I have set of 10 different values like - ...
3
votes
2answers
46 views

Which multilevel software should I choose?

I have used packages in R thus far for MLM, but now I need to do MLM with complex survey data, and as I understand it, none of the MLM packages in R can cope with the complex weighting needed to ...
1
vote
0answers
26 views

Statistical quality criteria for classifiers and recommenders

I want to know several points regarding the evaluation of data sets. I would like to know which metrics are the best for the evaluation of: a) recommenders and classifiers b) online and offline ...
0
votes
0answers
14 views

Is this interpretation of mixed ordinal logistic regression correct?

I am doing mixed ordinal logistic regression using clmm function in ordinal package. Before running the clmm model I have changed my DV into ordinal variable using: ...
0
votes
0answers
17 views

Forcing the order of variable in a decision tree in R [migrated]

I would like to build a decision tree in R. Is there a function or workaround, to specify the order of the variables in the tree? For example if A, B and C are inputs I would like to say: split first ...
0
votes
0answers
34 views

Linear regression for classification

Suppose, I have a classification problem with 2 classes (0 and 1) and evaluation criteria is AUC. I used the following method: fit a linear regression and then pass its predictions through the ...
1
vote
0answers
20 views

Johansen Test in python

How to get the trace statistics from the Johansen test for cointegration in python. Also, i tried to search it myself on google, found the following website ...
-3
votes
0answers
25 views

Reject or Accept the Hypothesis [on hold]

Simply . I am confuse that how can I know that I may reject or accept the H. ? what would be the most significant value ?
0
votes
0answers
10 views

Similarity scoring to compare multi-dimensional datasets

I am trying to come up with a mechanism of scoring a set of multidimensional datasets based on a similarity with an ideal dataset. Each dataset will all have the same dimensions along with the ideal. ...
0
votes
0answers
16 views

Auto-correlation vs. number of observation periods

I've just read an excellent post mix model I've a question connected to that. Roland, can you recommend any reference to a comment that if one have not enough observation periods then it is ...
0
votes
0answers
6 views

How to shorten the detection time of adaboost algorithm?

I'm working on a license plate detection using OpenCV's adaboost algorithm. However, after training, it shows that the detection takes 3200ms for a single image, where the image size I used is ...
0
votes
0answers
5 views

Clusteriod questions

I would like to clear some things up because I'm confusing everything. A $clusteriod$ is a coordinate for the mean value of a cluster? So if I have a 2-d .csv file I wish to perform kmeans, the ...
0
votes
0answers
16 views

Identifying topic name

When we perform Latent Dirichlet allocation on a set of documents to cluster, just assume give n=5 topics. How can we assign the topic name for these topics after performing LDA? I would like to give ...
0
votes
0answers
14 views

How to implement Exponential Histograms

I am having trouble in understanding the concept of exponential histograms. They are known to be much efficient for maintaining statistics. I have read it in this article but cant understand how they ...
1
vote
1answer
43 views

Learner in R to predict data from a complex function: if a>b then a*b else a+b

What sort of general purpose learner could learn the data generated by the following function: if a>b then a*b else a+b or something of that sort of complexity. Ideally something general enough to be ...
0
votes
0answers
27 views

Hayashi yoshida estimator for correlation not coming between -1 to 1

I took two time series data with 141 data points in total with time stamps. i found out actual correlation between them which is about 0.97. Now i find the Hayashi Yoshida estimator for correlation. ...
1
vote
0answers
11 views

R function equal to excel CHIINV [migrated]

I'm looking for a function which do the same thing as excel's CHIINV. From Microsoft documentation, the definition of CHIINV is Returns the inverse of the right-tailed probability of the chi-squared ...
2
votes
1answer
15 views

Inverse sampling for discrete data

I have to pick a ball from a set of balls. Each ball has a size, so I have a distribution for ball sizes (I assume a number between 0-1). I want to pick a new ball each at step with the probability ...
0
votes
1answer
38 views

Determining sample size for AB test with proportion greater than one

So I'm pretty sure I'm thinking about this all wrong, but.. I'm trying to run an AB test on a web platform that will increase the total number shares to a social network (incredibly exciting, I know). ...
0
votes
0answers
4 views

Lagrange multiplier method [migrated]

I am doing some data mining algorithm self learning tutorial. I came up with a problem which I need your help to solve. In order to minimize the resource consumption, a car manufacturer considers how ...
1
vote
1answer
17 views

What statistical test to use to examine attitude and which components have strong/weak influnces on attitude? 4-point Likert Scale survey

This is a quantitative study using survey to examine attitude towards online reading. In the survey, there are 5 main components which contribute to overall attitude. Each component has different ...
0
votes
0answers
17 views

Multiple regression with many observations per case

I need to analyse the results of a psychology experiment which had a repeated measures design, i.e. all subjects underwent both treatment A and treatment B. There are 27 subjects with many trials ...
0
votes
0answers
11 views

Derivation of the variance of the sample size in probability sampling

I am trying to understand how to derive the variance of the sample size $n$ in a random probability sample from a population of size $N$ with units $i=1,...,N$. Let $I_i$ be a random variable for $i$ ...

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