Day 5 practical instructions

On Monday you’ll be working together as a group to better understand multivariate twin models, including the Independent Pathway Model (IPM) and Common Pathway Model (CPM) and how these are estimated using OpenMx.


  1. We will use a workbook (Word file) as the basis of this tutorial, but you are asked to answer the questions that are in the workbook in this survey; this allows the tutors to monitor your progress. Make sure that all of you have the workbook open during the tutorial.

  2. Only one person should fill in the survey. It may work best if another person shares their screen to run the chunks of R script for the whole group to see.

  3. Throughout the practical, you will be asked to work out solutions to problems and to share your solutions using this survey. Please discuss and debate your answers among yourselves before asking the Scribe to put down your group answer in Qualtrics. Everyone should try to participate. After you have collectively come up with your best answer, put that answer in the answer box.

  4. The workbook asks you to copy and paste pieces of R script. Everyone should have R Studio open on their computer and everyone should run it together at the same time. When prompted in the workbook, run the relevant Section of the R script line by line (e.g., hitting Ctr + Enter, or Apple + Enter) or in small chunks of code. The R scripts are broken up into Sections. Please don’t skip ahead - keep pace with the Qualtrics survey. Everyone should work through the survey and script together.

  5. No cheating: Don’t skip ahead in the survey or in the workbook to get the answers. The point of all this isn’t to get a good “score” - it’s to learn! It is important to stop reading in the workbook when you have reached a question, as sometimes the answer to the question is provided shortly after the question to keep things going.

  6. Relatedly, it is easy to just cut and paste the R code and keep going, but try to understand what the code says, what is actually being calculated and whether you understand the syntax, i.e. what you are doing!

  7. Try to get through all sections, but there is no need to rush. If you are unable to finish the whole practical in the allotted time you can finish it later by yourself.

  8. After Session B, a workbook with answers will be provided in the folder of today.

Copying files

Open the workshop computing environment

Open the workshop SSH client
Create a directory to hold today’s work:
mkdir day5

Change into that directory, and then copy over the exercises.
cd day5
cp /faculty/dirk/day5/ .*

trting to copy this to my Day 5 using this comand
barakm46@ip-10-0-201-17:~/Day5$ cp /faculty/dirk/day5/ .*

I’m getting this error
cp: -r not specified; omitting directory ‘/faculty/dirk/day5/’
cp: -r not specified; omitting directory ‘.’

Wat could be the reason?

cp /faculty/dirk/day5/* .

It works for me.


Thank you. This works for me too