FAQ Database Discussion Community


Cronbach's alpha, by Category, in New Column in SAS

sas,correlation
I am new in SAS and I am trying to calculate Cronbach's alpha. The code I am using is: proc corr data=test alpha; var A B C; run; However, This way I only get the Cronbach's alpha in a table in the results section. Is there a way by only...

Correlate by levels of a variable in R

r,correlation
I would like to correlate two variables and have the output reported separately for levels of a third variable. My data are similar to this example: var1 <- c(7, 8, 9, 10, 11, 12) var2 <- c(18, 17, 16, 15, 14, 13) categories <- c(1, 2, 3, 1, 2, 3)...

Quantifying importance of variables in Canonical Correspondence Analysis using R? (x-post from researchgate)

r,statistics,correlation,vegan
I currently have species abundance data for multiple lakes along with measurements of some environmental variables of those lakes. I decided to do Canonical Correspondence Analysis of the data in R, as demonstrated by ter Braak and Verdenschot (1995), see link: http://link.springer.com/article/10.1007%2FBF00877430 (section: "Ranking environmental variables in importance") I am not...

Smart way to loop over all rows in A and correlate with all columns in B

r,performance,for-loop,matrix,correlation
First post, so be gentle ;-) I have a scenario, where I want to correlate all the rows of mat A (around 50,000) with all columns of mat B (around 100). I have solved this by doing so: output = c() for( i in 1:nrow(A) ){ for(j in 1:ncol(B) ){...

Computing the correlation coefficient between two multi-dimensional arrays

python,arrays,numpy,scipy,correlation
I have two arrays that have the shapes N X T and M X T. I'd like to compute the correlation coefficient across T between every possible pair of rows n and m (from N and M, respectively). What's the fastest, most pythonic way to do this? (Looping over N...

I want to do correlation for many data frame

r,function,loops,correlation
i have almost 13 files and i want to conduct three types of correlations to it. all the files have the same content except the values. for example: v1 v2 v3 v4 v5 v6 v7 v8 ........... v50 first correclation between v6 and v20 second correlation between v7 and v21...

Correlate a single time series with a large number of time series

python,numpy,correlation
I have a large number (M) of time series, each with N time points, stored in an MxN matrix. Then I also have a separate time series with N time points that I would like to correlate with all the time series in the matrix. An easy solution is to...

Is it possible to create data with a specific slope and pearson correlation coefficient in R?

r,correlation,linear
For example, I would like two variables, x and y to have a correlation coefficient of 0.7 and a slope of 1.5, with a specified mean and sample size for both variables. I don't care if the data is normal or not. I messed around with MASS a lot, using...

Rolling average pairwise correlation - code doesn't work as expected

r,statistics,time-series,correlation,xts
I have an xts time series object: head(mtrx) ADS.DE.Close ALV.DE.Close BAS.DE.Close BAYN.DE.Close BEI.DE.Close BMW.DE.Close CBK.DE.Close CON.DE.Close DAI.DE.Close 2007-12-28 01:00:00 51.26 147.95 101.41 62.53 53.00 42.35 21.04 86.06 66.50 2008-01-02 01:00:00 50.00 145.92 100.94 61.45 52.39 42.73 20.75 83.76 64.68 2008-01-03 01:00:00 50.09 144.93 101.60 61.71 51.18 42.09 20.48 81.74 62.91...

Pairwise correlations over rolling periods ignoring double calculations

matrix,stata,correlation
I am trying to compute pairwise correlations over rolling windows for n= 40 variables where all rolled pairwise correlations for 2 given variables are saved in a new variable. My dataset has the following structure: Date V1 V2 V3 . . . 01/01/2009 0.3 0.6 0.5 02/01/2009 0.1 0.5 0.2...

Creating a correlation loop to print and save png for 30 different data sets

r,loops,correlation
I'm new to stackoverflow but have found the community amazingly helpful in all my previous questions. However, I couldn't quite find an answer to this question so here I am. My question has to deal with multiple data sets that I have and if there is a way to loop...

Finding aggregate correlation of multiple columns against one column in r

r,correlation
I have a data frame with 11 columns out of which 9 are numeric. I am trying to find out the correlation of 8 columns together against the remaining column i.e., correlation of 8 variables with 1 variable which should generate one value of correlation instead of generating 9 different...

grouped correlation loop in r

r,loops,correlation
I want to calculate the correlation between Col1 and all of the other columns for each group. My input data set looks like this: Group1 Col1 Col2 Col3 Col4 A 3 1 0 1 A 8 0 1 0 B 4 1 1 1 B 2 1 0 1 And...

Making sense of CCA (Matlab implementation) 2

matlab,correlation,cross-correlation
I am using CCA for my work and want to understand something. This is my MATLAB code. I have only taken 100 samples to better understand the concepts of CCA. clc;clear all;close all; load carbig; data = [Displacement Horsepower Weight Acceleration MPG]; data(isnan(data))=0; X = data(1:100,1:3); Y = data(1:100,4:5); [wx,wy,~,U,V]...

R: Create dataset with specific correlation in r

r,random,dataset,correlation
How can i create a dataset with two columns having a specific correlation to each other? I want to be able to define the number of values which will be created and specify the correlation the output should have. The question is similar to this one: Generate numbers with specific...

Spearman - pairwise correlation

r,correlation
I have a data frame who looks like this (the real ones has 7000+ rows and 17 columns): V1 V2 V3 V4 1 93 98 79 170 2 17 17 22 85 3 1 57 137 320 4 9 1 0 440 5 NA NA NA 22 I would like...

Creating Dummy Sets in MATLAB for statistics

matlab,correlation,categorical-data
i am looking at creating dummy sets in MATLAB, first i created an array of random variable with 10 instances of min=5 and max =10, and here is my code r = (10-5).*rand(10,1) + 5; Please I need help on how to create the following; 1: create additional variable that...

SoapUI correlation (property transfer)

properties,soapui,correlation
I have a REST request that respond with the following: { "access_token": "eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsIng1dCI6IlQwWE8xNnAtMmZzMWxremV5", "expires_in": 2592000, "token_type": "Bearer" } I want to take the value of access_token, store it in a property and reuse it for two subsequent requests. Following some tutorial here, when running the request that obtains the access_token...

Fast rolling correlation in Matlab

matlab,correlation,accumarray
I am trying to derive a function for calculating a moving/rolling correlation for two vectors and speed is a high priority, since I need to apply this function in an array function. What I have (which is too slow) is this: Data1 = rand(3000,1); Data2 = rand(3000,1); function y =...

Link and brush in Matplotlib/Pandas — plotting selected points from a plot in another plot

python,pandas,matplotlib,correlation
I'm wondering how could I implement some sort of 'link and brush' in Matplotlib/Pandas or if there is another lib that provides this. For instance, using the scatter-plot matrix from Pandas I obtained this graph: It can be seen, for example, that there is a relation between some points of...

Getting different correlation values for the same combination of vectors

r,correlation
why am I getting different correlations for the same combination below? > cor(finalDB[2:6],use="complete.obs") rocky1Rating rocky2Rating rocky3Rating rocky4Rating rocky5Rating rocky1Rating 1.0000000 ***0.6476523*** 0.5435555 0.4964198 0.3483168 rocky2Rating 0.6476523 1.0000000 0.7507204 0.6653651 0.5288312 rocky3Rating 0.5435555 0.7507204 1.0000000 0.7284123 0.5897088 rocky4Rating 0.4964198 0.6653651 0.7284123 1.0000000 0.6006595 rocky5Rating 0.3483168 0.5288312 0.5897088 0.6006595 1.0000000 > cor(finalDB[2],finalDB[3],use...

How to use `cor.test` for correlation of specific columns?

r,correlation
I have the following data example: A<-rnorm(100) B<-rnorm(100) C<-rnorm(100) v1<-as.numeric(c(1:100)) v2<-as.numeric(c(2:101)) v3<-as.numeric(c(3:102)) v2[50]<-NA v3[60]<-NA v3[61]<-NA df<-data.frame(A,B,C,v1,v2,v3) As you can see df has 1 NA in column 5, and 2 NA's in column 6. Now I would like to make a correlation matrix of col1 and 3 on the one hand,...

Jmeter : Application uses _session_id in cookie to maintain session. It is being maintained from login to logout. I need to correlate it

regex,jmeter,session-cookies,correlation
Jmeter : Application uses _session_id in cookie to maintain session. It is visible in get request. It is being maintained from the time of login till logout. I need to correlate it to test the performance. I have used regex extractor to extract the _session_id as below: In regular expression...

Cannonical Correlation Analysis

matlab,statistics,correlation
I have just started working using CCA in Matlab. I have two vectors X and Y of dimension 60x1920 and 60x1536 with the number of samples being 60 and variables in the different set of vectors being 1920 and 1536 respectively. I want to know do CCA for reducing them...

Bootstrap correlation CI with increasing sample size

r,ggplot2,replication,correlation,confidence-interval
I would like to demonstrate how the width of a 95% confidence interval around a correlation changes with increasing sample size, from n = 10 to n=100 in increments of 5 samples per round. I would assume we can use a bootstrap function to do this and replicate each round...

Customizing what variables are shown on the sides and on the top of the outputs `corrplot` or `corrgram` in R

r,data-visualization,heatmap,correlation,r-corrplot
Suppose I have the following data: > print(data) date gdp unemp_rate cpi_index rpi_index var1 var2 var3 var4 1 8/31/2009 23:00:00 0.002000575 0.0 0.006539081 0.008466604 0.041601305 0.193230747 0.002260496 0.016428674 2 12/1/2009 0:00:00 0.003890642 0.0 0.007278347 0.011660448 0.012048193 0.022703903 0.003004489 0.015541372 3 3/1/2010 0:00:00 0.005088272 0.2 0.007439852 0.011065007 0.028750000 -0.222946928 0.002789741 0.015225019...

Pandas Correlation Groupby

python,pandas,group-by,correlation
Assuming I have a dataframe similar to the below, how would I get the correlation between 2 specific columns and then group by the 'ID' column? I believe the Pandas 'corr' method finds the correlation between all columns. If possible I would also like to know how I could find...

Error:3201 during Cordova App deployment on Windows

correlation,windows-applications,visual-studio-cordova
I am trying to create package of cordova application. App Passes the local validations but gives following error on file uploading: 3201: The publisher display name, $username$, specified in the package doesn’t match the publisher name, My App, that’s associated with the developer account. Its look like my AppxManifest.xml file...

Plot only one or few rows of a correlation matrix

python,numpy,matplotlib,heatmap,correlation
I have a correlation matrix named corrdata that I calculated using numpy.corrcoef. Then what I do is extract one or a few rows of this matrix, and now just want to plot them instead of the whole matrix. Because the matrix is no longer square, it is not possible to...

Convert an image to a 2D array of coordinates in Python for two point correlation

python,opencv,numpy,fft,correlation
I need to perform two-point correlation function from astroML Python module, my data is originally a jpg image, black and white, and I convert it to binary image using OpenCV image thresholding(not sure that I did it right). The question is how now I convert the 2D binary matrix or...

Subsetting Matrix Based on contents of dataframe

r,matrix,correlation
I have an 100X100 correlation matrix with zip codes as the column and row names. I also have a data frame that contains the latitude and longitude for all zipcdes and a function that calculates the distance based on lat and long. Here is a snippet of the correlation matrix...

How to use biserial to calculate correlation between continuous and categorical variable?

r,correlation,continuous,categorical-data
I am trying to calculate the correlation between x (continuous variable) and y (categorical variable) in R. The function biserial in the psych package is used to calculate this. See here. But when I actually used it, I got a warning message and NA as the correlation: Warning message: In...

Trigger by suffix from same element class

javascript,jquery,triggers,correlation,prefix
I want make every button which have suffix class -dummy (let's call it "dummy") to trigger another button who have same class but without that suffix (call it "real button"). <button class="btn-submit hidden"> triggered by <button class="btn-submit-dummy"> <button class="btn-edit hidden"> triggered by <button class="btn-edit-dummy"> <button class="btn-delete"> triggered by nothing since...

cummerbund, scatterplots and a statistical value

r,correlation
I'm working in cummerbund with cuffdiff files from a RNA-Seq analysis. I made a scatterplot with two conditions, but I'd like to see de correlation value of my data. Is it possible? Is there a command to do this? Any idea? Thanks!!

Rolling Mean of Rolling Correlation dataframe in Python?

python,matrix,pandas,yahoo,correlation
Python beginner here. What I've done so far: Imported price data from Yahoo Finance from a list of stocks. Between the stocks (every combination), computed the 20 day rolling correlation into a dataframe. I would like to: 1) Calculate the 200 day simple moving average for each of the 20...