Tutorial: Text (1/21)


…\DirectRT\samples\1 bare bones\text.csv


In this first sample, you'll see the bare minimum it takes to run a DirectRT session. There are no external stimuli and no stimulus lists. Everything is located in the input file. Using Excel or a similar spreadsheet program, open the file indicated above to see what the input looks like.

The block and trial columns are for your own reference. They'll be written to your data file. The trial column also serves a useful purpose when you want to use skips and jumps. The block column can also indicate you don't want data written to the data file if you use a 0.

The bgr and wgr columns are for randomization. Currently they're all set to 0 which means that no randomization of trials will occur.

The style column indicates that all trials are to be presented in style 1. More detail on styles will follow shortly in another sample.

Then come the three critical columns: Stim, Loc and Time. In this sample there is only one set for each trial.

In the Stim column, the ~ indicates that the stimulus is the actual text in the cell. The Loc column tells DirectRT where to place the stimulus and whether to clear the screen or append the stimulus to the previous screen. 0,0,1 is a shorthand way of telling DirectRT to center the stimulus and to present it on a fresh screen.

Finally, the Time column tells DirectRT what to do after the screen is displayed. In this case, 'RT:any' indicates that it should wait for any key response.

Try running the input file by choosing Select and Run Input File from the file menu in DirectRT.  When you see each word appear, press any key and your response time will be recorded.

Now, let's look at the data you just produced--these files will be located in a data subfolder along with the input file--you can view them in Excel. Note that there are two data files that DirectRT produces for each session: a simple one useful for most needs, and a more detailed one called a log file that records everything including actual display times for your various stimuli. Most of the columns in the data files should self-explanatory. The two most important columns are name and RT. This tells you which key you pressed and your reaction time. See Output Files for the details regarding any specific column.

That's it! That's a bare bones DirectRT session. As an exercise, try changing some of the stimulus values in the input file (e.g., change dog to puppy) save the file and re-run it. Be sure to save the file in the .csv format even if your spreadsheet application warns you that you'll lose formatting. The .csv format is critical because that's what makes the input files independent of any particular spreadsheet application.

Now we'll start adding some more DirectRT features…