Logger items

Typically, you will not only want participants to respond during an experiment, you will also want to log their responses to a data file for analysis. This is where the logger item comes in.

Always triple-check whether OpenSesame has logged all relevant variables!

Selecting variables

In the logger item you can indicate which variables you wish to log. By default the logger tries to auto-detect and log all variables. This is a safe bet, but results in large datafiles, with lots of unnecessary information.

If you deselect the auto-detect option, you can select variables from the list, which contains all (global) variables that OpenSesame is aware of. If, for some reason, the variable that you want to log does not appear in the list, you can add it using the Add custom variable button.

If you are unsure which variables you want to log, you can click on the Smart select button, which will select all variables that are likely to be of interest.

By default, the experiment is aborted if OpenSesame attempts to log a variable that has not been set. You can change this by enabling the Use 'NA' for variables that have not been set option, in which case missing variables are assigned the value 'NA'. This is convenient if you want to log a variable that is set only later in the experiment.

You can find out more about variables in OpenSesame on the website <http://osdoc.cogsci.nl/usage/variables-and-conditional-qifq-statements>.

Format of the logfile

The logfile is in plain-text, comma-separated format. This format can be viewed in most text-editors (although Windows Notepad may not handle the line-endings properly) and spreadsheets.

Merging data files

If you prefer to have all participant data in a single spreadsheet, you can merge the OpenSesame logfiles using the online spreadsheet merger <http://www.cogsci.nl/software/online-spreadsheet-merger>.