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Template: Variable Fixation Screen Duration and Reporting the Duration Online
#1
Variable Fixation Screen Duration and Reporting the Duration Online

Required Experiment Builder Version: 1.5.58 or higher
EyeLink Required: Yes
Type: Complete Example
Difficulty Level: Easy to Intermediate

This example illustrates:
  • How to use Python function random.randrange() to generate a random duration
Description:

This example experiment consists of ten trials. Each trial begins with a drift correct screen. Then a fixation cross appears on the screen. The fixation cross remains on the screen for a random time interval that is between 500 and 1000 msec. A picture then appears on the screen for 3000 msec, after which the trial ends. The durations of the fixation crosses are controlled by setting the value of a variable to a random number between 500 and 1000. The desired durations (the values set using the random number generator) and the actual durations of the fixation crosses are written to the EDF file. The durations of the pictures are also written to the EDF file so that the experimenter can verify that the pictures were displayed for the desired duration of 3000 msec.

**Additional detailed information about the project is given in the notes section for most nodes. To see notes for a given node, either mouse over that node or click on it to display the notes window. If the notes window is not visible, go to the "View" drop down menu in Experiment Builder, select "Properties", and check "Note".

NOTE: Please see our Randomizing Variables Outside of Data Source in Experiment Builder and Data Source Randomization in Experiment Builder Webinars for more randomization methods.

Instructions:
  1. Download the Variable_Fixation_Screen_Duration_and_Reporting_the_Duration_Online.ebz example from this message.
  2. Launch the Experiment Builder application.
  3. Unpack the Variable_Fixation_Screen_Duration_and_Reporting_the_Duration_Online.ebz file to a location on your Experiment Builder PC with "File menu -> Unpack".
  4. Open the project in Experiment Builder.
  5. Deploy the project to a new folder.
  6. Run the Variable_Fixation_Screen_Duration_and_Reporting_the_Duration_Online.exe from the deployed directory.


.ebz   Variable_Fixation_Screen_Duration_and_Reporting_the_Duration_Online.ebz (Size: 88.4 KB / Downloads: 34)