1. M

    Multivariate Outlier Detection

    Hi all, I want to compare the results of "classical multivariate mahalanobis distance" scores of 5 variables for 2 million cases and "minimum covariance determinant based mahalanobis distance" scores at 0.001 and 0.01 level respectively. Also I want to see this difference at the plot. In...
  2. C

    Help from Stata users

    Hello Stata users: I am looking to create a new variable (Number) that will count the number of members present in an existing room at a particular time. Here is an example of my data and what I am looking to do: Person DateEntered Room DateStayed Number 1 23March2014...
  3. D

    Converting syntax between python and STATA

    Dear colleagues, Im converting a code written in PYTHON to STATA and I'm stuck at the point when have to apply the iterative procedure. Cannot find the way to write the loop so that it includes the initial value and generates an estimate for lat. Has any of you got any experience with that...
  4. J

    R homework

    1. Fit appropriate regression models to describe relationship between the variables X and Y using the following three data sets separately. Use Y as the response and X as the explanatory variable. You must show all the necessary tables and fi gures for the model fi t and also comment on the fi...
  5. J

    r program. Draw the histogram of the eruption waiting periods in 'faithful '.

    #head(faithful) vct <- faithful$waiting #vct #is.vector(vct) range(vct) cls.boundary <- seq(40,100,by=10) #cls.boundary cut.vct <- cut(vct,cls.boundary,right=FALSE) #str(cut.vct) freq<-table(cut.vct) show<-cbind(freq) #show hist(show) Is this right? The Y-axis(frequency) of the...
  6. R

    Which programming language/database to learn?

    I'm interested in pursuing a career in biostatistics, and I'm wondering which language/database will be useful in the field of biostatistics/epidemiology. As of now I only have a basic knowledge of C an R. Thank you.
  7. J

    How can i compute the following situation in R?

    Suppose that an urn contains a number of black and a number of white balls, and suppose that it is known that the ratio of the numbers is $\frac{3}{1}$ but that it is not known whether the black or the white balls are more numerous. Find the estimator of the probability of drawing a black ball...
  8. S

    OC Curve Program

    One of my friends has asked me to help him write a program to calculate the "n" and "c" values (sampling size, accept number), only given alpha(confidence level) , beta(probibility of acceptance), p1(AQL) and p2(LTPD). I'm currently a computer science major that has taken a few statistics...
  9. S

    Entering values into a matrix from a loop command

    I have created a loop to generate a counter variable values that will then be entered into an OUTPUT matrix. Everything except for 1 line seems to be working. The line is here: matrix OUTPUT[`i', `j']=counter *STATA writes: counter not found. But then I write: display...
  10. G

    Freelance work

    We're a start-up here in Boston and we're looking to hire some freelance statisticians to help us build out capabilities in our analytics/intelligence platform. First off, my apologies if listing job opportunities here is inappropriate --> I took a look through the forum guidelines and...