1. S

    Need Appropriate Test for comparing a series of measurements from one bone to another

    My research involves taking measurements at 9 sections at different locations on the shaft of bones. I am having trouble determining which statistical methods I can use to test for significant difference in the distribution and change of the measurements as they progress along the shaft of the...
  2. T

    T series stationarity

    hay guys, i'm working on garch models, but a cant turn my returns stationary. how can i do it? i've tried whit log return (logxt - logxt-1) but it doesn't work. r function: log.return<-dff(log(x)) i've implemented some test and these are the results: #######KPSS Test for Trend...
  3. K

    Summarizing time series data

    Hello, Thank you very much for taking the time to read this! I have many (~70) time series showing the average body size (kg) for the ~50 years. Each time series is for the same species but from a different region/area. I would like to look at the change in body size over time and how...
  4. B

    PCA on time series

    Hi, excuse my poor english... I need to reduce number of indicators (and to perform a PCA) on dataset: year ind(1) ind(2) ... ind(n) 2000 x(1,1) x(1,2) ... x(1,n) ..... 2010 x(11,1) x(11,2) ... x(11,n) x(i,j) are quantitative values about indicators like production, resources, ecc. How...
  5. M

    sum to infinity

    Hi, just wondering can anyone tell em how to sum this term from k=1 to infinity? I used to know how to do it but I forgot, it's something to do with identifying a partial sum, it is the sum of (e^(-0.02k)) Thanks in advance.