User`s guide

E-Prime User’s Guide
Chapter 2: Using E-Studio
Page 27
However, subjects don’t always follow the instructions, so it is necessary to test the deviant cases
as well. For example, what happens when a subject presses a key that is not a valid response
key, or perhaps does not respond at all? In the current example, pressing the wrong key or a
non-response will not terminate the display, but the stimulus display will terminate when the
maximum duration for the stimulus object is reached. If the subject presses an invalid key, or
does not respond within 2000ms, the experiment will simply continue with the next trial. At this
point, it is important to verify that this is how the trial procedure is working. Later, it will also be
necessary to verify the distinction between these trials (e.g., valid response versus invalid or non-
response) through examination of the data file.
2.3.7.3 Verify expected displays
Verification of the core experiment also involves the examination of each of the displays. The
Fixation display presents a “+” for 1000ms. This display should be consistent in that the display
does not vary, nor does it terminate if the subject presses a key. However, the Stimulus display
should vary. The stimulus string presented should be different for each trial, and the duration of
the display is dependent upon the subject’s response (i.e., the stimulus is displayed until the
subject responds by pressing a valid key, or until the maximum duration of 2000ms has expired).
2.3.8 Perform Step 1.8: Verify the data logging of the
core experiment
2.3.8.1 Start E-DataAid and load the data
Once the core procedure has been verified, it is necessary to examine the data file in order to
determine that the information is logging correctly. The application that allows viewing and
editing of data files is E-DataAid. Open E-DataAid using the Tools menu in E-Studio. When E-
DataAid is launched, a screen such as the following will appear: