# matlab

1. ### Weibull distribution for data with zero's

Hi, Can any one tell me how to fit some data with zero's to a weibull fit using Matlab. I tried using Maximum Likelihood Estimator and wbfit. But I am experiencing problem because of zero's. It requires positive values. Thank you very much Vinay
2. ### ROC curve for ordinal regression goodness-of-fit

Hello everyone, I have a problem with the graphical output of a ROC curve I am calculating. I am sure it is very silly but I cannot figure out where I am going wrong. I estimate the probability of damage (damage levels 1 to 5) to a number of buildings given one continuous explanatory...
3. ### Help with assessing the correct dates for time series in MATLAB

First of all i am fairly new with MATLAB I have a single time series for unemployment from 1971 quarter 1 to 2013 quarter 1, hence the frequency of the timeseries is quarterly. I imported the series from an excel file, but when converting the vector to a timeseries object i have a problem...
4. ### Bootstrapping with One-way ANOVA design and confidence interval

Hello, I am new to this forum, and I need some helps in bootstrapping. I am using Matlab. So, here's the study design: I have three groups (Group1, Group2, Group3), 30 subjects/group each. They all have some brain imaging scans (FDG-PET). Within each group, I calculated some parameter...
5. ### [Matlab] One-way ANOVA with 2 covariates [HowTo?]

Hello everyone, (Big hello, my first post in this forum!) I was wondering how to do a one-way ANOVA with 2 covariates in Matlab. The problem is that I work with a variety of scripts and most are realized in matlab; also, I have absolutely no knowledge of R or any other powerful language...
6. ### PCA - To check

Hi I got a data set and tried my hand in doing PCA using SPSS and for the same set of data carried out PCA by using matlab program (first standardising data and then using princomp). I have got the PC1 Vs PC2 Vs PC3 plot to be different in both the cases. Can some one tell me which is...
7. ### [Matlab] - Stratified Sampling of Multidimentional Data

I want to divide a corpus into training & testing sets in a stratified fashion. The observation data points are arranged in a Matrix A as A=[16,3,0;12,6,4;19,2,1;.........;17,0,2;13,3,2] Each column of the matrix represent a distinct feature. In Matlab, the cvpartition(A,'holdout',p)...
8. ### SAS to MATLAB

Hi, I have a large SAS code which I need to translate to MATLAB code. So I have two questions. Is there any easy way of porting SAS code to MATLAB? As the chances of the prior question is slim; What is the easiest way of getting an overview of the syntax and commands of SAS. Is there...
9. ### Mixed effects modelling

Hey all, Im building a linear mixed effects model of a variable, lets say the headway time maintained by drivers in car following situations. I want to use a training dataset to come up with a linear regression model and validate this model by running it through several sets of validation data...
10. ### anova 3 way sum of square type - mtalb

Hi, I have written 3way-anova in c++. I have 3 factors, lets say a,b and c. The result of my code is the same as MATLAB when I use type I sum of squares. But when I change the data so that the number of replicates is so high for a number of cells and too low for other cells: I don't get the...
11. ### [Matlab] - 3D plot Matlab

Hi - im trying to do a 3D plot in Matlab I have a user defined function of the form: [Number,~,...] = myfunc(parameter,arg2,...) The first output argument (Number) is a real number. Parameter is a vector in 2 dimensional space. Can someone tell me how to plot Number on the z - axis...