Knowledge Base

Prepare the Experiment in E-Studio

Response Option Types

• numericalpredefined for response options with predefined values.
• numericalrange for response options within a range.

1. Click the Logging tab and select Tag.
2. Run the experiment in E-Studio.
3. After that, the experiment is ready to work with The Observer XT. The values of the attribute in a specific trial will be imported as numerical modifiers.

Notes

• The tag you specified in the procedure above is present in the log file of the E-Run experiment, which is the text file present in the same folder as your experiment.
• You can specify one response for each stimulus for import into The Observer XT. Multiple answers per stimulus is not supported.
• Warning: If you want to use numbers as responses, do not use an existing project created in The Observer XT 13 or earlier. Since this option did not exist in a previous version, it will result in errors in the Event log. Create a new project instead.

Ensure High Synchronicity Between The Observer XT and E-Prime

In order to ensure synchronicity with E-Run, The Observer XT needs to acquire the time information with the highest accuracy. To do so, it uses a package that runs in the E-Prime experiment. You must specify this package in all your experiments that work together with The Observer XT.

Note: A package is a re-usable block of E-Basic script that you can add to E-Prime experiments via the PackageCall objects.

Procedure

1. With the File Explorer, make sure that the file TheObserverXT.epk3 is present in the following two locations:

   • C:\Users\[user name]\Documents\My Experiments\3.0\Packages

     This is the default E-Prime search folder for packages.

     Note: If you use E-Prime 2, the correct folder for this package is C:\Users\[user name]\Documents\My Experiments\Packages. The package file extension is epk2.

   • C:\Program Files (x86)\Noldus\EPrime Server

     This is the installation folder of Noldus E-Prime Server. This package must be in that folder only if you installed Noldus E-Prime Server with a user account different from that you use when working with E-Prime. If the package file is not present, repeat installation of Noldus E-Prime Server.

     Note: If you use E-Prime 2, the correct folder for this package is C:\Program Files (x86)\Noldus\EPrime Server. The package file extension is epk2.

2. Specify the Packages Search Folders in E-Studio.

   1. In E-Studio, choose Tools > Options > Packages.

      Under User Search Folder you should see the default folder C:\Users\[user name]\Documents\My Experiments\3.0\Packages.

      Note: For E-Prime 2.0, the folder is C:\Users\[user name]\Documents\My Experiments\Packages.

   2. Under User Search Folder you should see a second location (C:\Program Files (x86)\Noldus\EPrime Server). If that is not the case, click the New button.

      Browse to C:\Program Files (x86)\Noldus\EPrime Server, then click OK.

   3. Now the Packages tab in the Options window should display both locations.

3. Specify the TheObserverXT package file in the E-Studio experiment.

   1. In E-Studio, open the experiment, and in the Experiment Explorer window double-click the experiment name.
   2. Click the Packages tab, then click the Add button.
   3. Select TheObserverXT, click OK. If this package is not visible, restart E-Studio.
   4. Click Apply, then OK. The package can now be inserted in the experiment.

4. Insert the PackageCall in the E-Studio experiment.

   1. In the Toolbox window, locate PackageCall, and drag it to the beginning of the first procedure.
   2. Result: An object named PackageCall1 is inserted.
   3. Double-click PackageCall1, click the General tab, and from the Package list select TheObserverXT. From the Routine list select SyncTime.
   4. Click the Common tab. Ignore the warning and click OK.
   5. Next to Name, rename PackageCall1 to SyncTime, and click OK.
   6. Result: In the Structure window, the PackageCall object is now named SyncTime.
5. Run the experiment once (E-Run > Run, or press F7) then save the experiment.

Notes

• The SyncTime routine of the TheObserverXT package reads the timestamps with high accuracy from E-Run, and writes it down in a text file named NoldusSync.txt. This time will be read by Noldus E-Prime Server when sending the E-Prime data to The Observer XT PC.
• The file NoldusSync.txt is stored in the same location as that of the experiment file.
• If the TheObserverXT package is not added to your E-Prime experiment, when importing the data from E-Prime, The Observer XT shows a message in the Comment column of the first line of the E-Prime event log, that accurate synchronization is not possible for that E-Prime data set. The E-Prime event log is still added to the observation, but aligned with the Observer XT data with a 1-second accuracy.
• If you use E-Prime 2.0, see the Technical Note - E-Prime - The Observer 12.5, which you can also find on the Observer XT 12.5 download web page.

Acquire Data

Things to Check First

1. On the E-Prime PC, make sure to close the E-Run window.
2. On the E-Prime PC, make sure that Noldus E-Prime Server is running in the background. To do so, check that its icon is visible in the taskbar. If Noldus E-Prime Server is not running, in the Apps screen choose Noldus > E-Prime Server (in Windows 7, choose Start > All Programs > Noldus > E-Prime Server > E-Prime Server).
3. On the E-Prime PC, in the Noldus E-Prime Server window, click Start. Result: Noldus E-Prime Server says "Server is running".

Important: Do not click Exit until your test sessions are finished!

The Start button is not available when the server is already running.

Procedure

1. On the Observer XT PC, open your project in The Observer XT. Optionally, create a coding scheme which you can use to annotate the test participant's behavior manually. See The Observer XT Help for instructions.
2. Create a new observation (Alt+F6) and give it a name, then click OK. Result: The E-Prime Status window opens. The status is Ready to start.
3. Ask your test participant to sit in front of the test PC, and give him/her the necessary instructions.
4. On the Observer XT PC, when ready, click the Start observation button. Result: The E-Prime Status window says: Connection: Connected. Status: Waiting for E-Prime.
5. On the E-Prime PC, the experiment starts. Insert the subject and session data, then let the test participant carry out the assigned tasks. The Noldus E-Prime Server window says Client connected.
6. On the Observer XT PC, optionally manually code the test participant's behavior. When the experiment in E-Prime is finished, the E-Prime Status window says Finished. The Noldus E-Prime Server says Client disconnected.
7. On the Observer XT PC, stop the observation by clicking the Stop observation button.
8. The E-Prime events are imported as a new event log named E-Prime in the current observation.

Notes

• In order for the Noldus E-Prime Server to start correctly, the experiment script file (ebs3/ebs2 file) must be selected under E-Prime Experiment. See the Set up communication - the E-Prime PC section for details.

• If you create an observation before starting Noldus E-Prime Server, the E-Prime Status window on the Observer XT PC says Connection: Not connected. To solve this problem, do the following:

  1. In The Observer XT, click another item in the Project Explorer, for example the coding scheme. This action closes the observation.
  2. On the E-Prime PC, in Noldus E-Prime Server, click the Start button.
  3. In The Observer XT, in the Project Explorer, click the name of that observation. This re-opens the observation. Note that the observation name is labeled with a yellow triangle icon. This indicates that the observation has yet to be started.
  4. The E-Prime Status window now says Connection: Connected. You are ready to start the observation.
• Warning: Make sure that you stop the observation in The Observer XT only when the E-Prime Status window says Connection: Connected and Status: Finished. If you stop before this, The Observer XT will not import the E-Prime data for that observation.
• If you cancel the run on the E-Prime PC after starting the observation, for example when clicking Cancel in one of the dialogs that appear at the start of the run, connection is lost for that observation. On the Observer XT PC, stop the observation, delete it, and create a new one.

• There may be a significant delay (30 seconds or more) between the start of the observation and the start of E-Run. This could be due to a number of factors, such as:

  • The driver software of the E-Prime hardware key is not up-to-date. Go to http://sentinelcustomer.safenet-inc.com/sentineldownloads/ and download Sentinel HASP/LDK Windows GUI Run-time Installer. Next, remove the E-Prime hardware key from the E-Prime PC and launch installation of the driver. After installation is complete, insert the hardware key in the E-Prime PC and start E-Studio.
  • The E-Prime PC has other hardware installed that conflicts with E-Prime, for example an additional network card. See the In case of complex setups section for details.
• When E-Prime data are imported into The Observer XT, it adds two subjects to the Coding Scheme: User and System. When you manually score events, The Observer XT expects that for each event you first score a subject and then a behavior. Define a subject in the Coding Scheme. Then choose Setup > Project Settings > Scoring Options and select Auto-record subject. You then only need to score the subject once at the start of the test.

Scoring Data Offline

Once you finish an observation, the E-Prime data are sent to The Observer XT. It may happen that you want to review the observation, possibly with external video, and score events manually. However, after data import, the coding scheme has two additional subjects: User and System. This means that every time you want to score an event manually, you must score the subject in The Observer XT's Codes window before you can score the event (behavior). To prevent this from happening, and to reduce the number of key presses, you can use the Auto-record subject function. With this option, The Observer XT assumes you will be scoring events for the first subject you score in an observation session.

1. In The Observer XT, choose Setup > Project Settings > Scoring Options.
2. Select Auto-record Subject.
3. If they are not already present, define one or more subjects (roles) in the coding scheme, which can be used to score events manually.
4. Open and start the observation as usual.
5. Position the observation (or video) at the time where you want to enter the event.
6. Score the event as usual, including the subject: [Subject] - [Behavior] - [Modifiers].
7. The next time you score an event, that subject is scored automatically. Complete the event with the Behavior and Modifiers.

For more information, see Auto-record Subject in The Observer XT Help.

Note: The subjects User and System added after E-Prime data import are not shown in the Codes window.

Analyze Data

How E-Prime Events Are Stored in The Observer XT

Event Files

The data of E-Prime are stored in a separate event file named E-Prime. You can see this in the tree view of the Project Explorer. Click the observation name, and open Event Files.

• E-Prime contains all events imported from the E-Prime computer.
• Event log is the event file that The Observer XT creates by default when you create an observation. If you code events manually during the observation, the events are written to this file. If you do not code events, Event log only contains two lines that mark the start and the end time of the observation.

Click E-Prime to open the E-Prime event log.

Two Subjects: System and User

In the E-Prime event log, the column named Subject specifies the subject of the event in each row.

• System: for all events determined by E-Prime (for example, a stimulus presentation).
• User: for all responses by the test participant.

System Events

A state event like the presentation of a stimulus is indicated by two rows:

• The start row (with a green symbol in the Behavior column). The start time is the value of OnsetTime of the E-object in E-Prime.
• The stop row (with a red symbol in the Behavior column). The stop time is the value of OnsetTime + Duration of the E-object in E-Prime.

Note that the times in the event log may differ from the times in the E-Prime output file (a text file generated by E-Run). This is normal, since the time stamps are corrected to ensure millisecond-accurate synchrony between E-Prime and The Observer XT.

For system events, the name shown in the Behavior column is always Show followed by the name of the E-object.

User Responses

A point event like the user response is indicated by one row, with a blue circle in the Behavior column. The time of the event is the value of OnsetTime of the E-object in E-Prime.

The Modifier column shows two modifiers:

• Response: followed by the character(s) entered by the test participant.
• Correct: followed by the correct response for the corresponding stimulus (that is set in the E-Prime Trial List).

Numerical Responses

Modifiers are by default nominal, unless you specified in E-Prime that they should be imported as numerical. Numerical responses are then imported into the Event log as numerical modifiers.

Notes

• If events are missing or incomplete, it could be due to wrong settings in E-Prime. For example, if RTTime is not selected in E-Prime logging settings, user answers will not be imported in The Observer XT. If CRESP or RESP are not selected, an event line is imported but does not contain the corresponding modifier (correct response or actual response, respectively). If neither of the two is selected, the event is not imported at all.
• If the Subject, Behavior, or Modifier columns are not shown in the E-Prime event log, right-click one of the column headers and select them.
• It is not possible to remove Show from the name of system events. It is also not possible to customize the behavior Answer and the part of its modifiers Correct: and Response:. You can only customize the responses; to do so, edit the values in the Trial List.
• See the Prepare the Experiment in E-Studio section for how to customize the information in the E-Prime events sent to The Observer XT.
• If the first event line of the E-Prime event log contains the message The E-Prime data could not be synchronized automatically in the Comment column, it means that E-Prime could not use the TheObserverXT package correctly, or the package was not installed. In such cases the E-Prime event log is added to the observation and aligned with other data with a 1-second accuracy.
• Note that the times in the event log may differ from the times in the E-Prime output file (a text file generated by E-Run). This is normal, since the time stamps are corrected to ensure millisecond-accurate synchrony between E-Prime and The Observer XT.

Synchronicity Between E-Prime and The Observer XT Data

We advise connecting the Observer XT PC and the E-Prime PC to a local area network (LAN). In most cases the network speed is high enough to have a negligible delay between the start of the observation in The Observer XT and the start of the E-Run experiment.

Source: The Observer XT 17 - Technical Note - E-Prime