Minitab

General Linear Model in Minitab

This procedure gives almost similar results to the Pipestat!!!

  1. In our design Accommodation had three levels (Coll, consist, mp) and the Participants were nested inside the accommodation (one Participant could participate in only one condition or a between-subject design)
  2. These both were crosses with Distance (5 levels)
  3. All of these were again crossed with repetition of distances.
  4. The trick is to consider the nested variables as a single unit when describing the model in Minitab
  5. So the model for this design would be
    • condition participant(condition)
    • distance distance*condition distance*participant(condition)
    • repetition repetition*condition repetition*participant(condition) repetition*distance  repetition*distance*condition repetition*distance*participant(condition)
  6. It is much better to do it in Pipestat as it figures out the model itself rather than us specifying it.

My original motivation to study the model was to do post-hoc test REGWQ etc. in Minitab but it looks like it does not provide that test.

July 25, 2012 | Categories: Minitab, Statistics | Comments Off

Minitab Tricks

Importing .dat, .csv, xls file in Minitab

  • File -> Open Worksheet  [Choose .dat, .csv etc]

Removing empty cells in boxplot for between-subject design

  • Double click the axis variable.
  • Uncheck: “Include empty cells”.
  • This shows only those ticks that has some data in it, which is very useful in case of between-subject design, as the participants are divided into different treatment groups.

Changing order of x-axis groups

Minitab picks a default ordering for x-axis groups (usually Alphabetical or Numeric ordering) If you want to change the order of group variables on x-axis (e.g.  Low, Medium, High to Medium, Low, High):

  • Select the column in the data window which represents the group in the graph.
  • Right click and select Column->Value Order
  • Select User-specified order
  • Add the desired order, Click OK
  • Any graph from now onward will follow that order

 

Changing color of x-axis groups

  • The colors for groups can be selected in the dialog box at Tools->Options->Graphics-> Data View With Groups -> Symbol and Line Colors
  • You can also change color for individual groups or sub-groups by double clicking on the bars and choosing appropriate attributes in the dialog box.
  • Before double clicking, click just once to switch between different grouping variables.

January 25, 2012 | Categories: Minitab, Statistics | Comments Off

Tags

OpenGL