Displaying feedback after each block in E-Prime

If you don’t use E-Prime for psychological experiments, skip this post.
It’s written for the benefit of psychologists who have the misfortune of using E-Prime without a programmer husband to help them out.

E-Prime only allows you to display feedback after each stimulus:

What if you want to show feedback after each block? This won’t work:

Because in this case, only the last response in each block will be added to the statistics. Worse, the feedback screen will show “Correct” or “Incorrect”, according to that last response.

I succeeded to solve the problem by taking some of the Basic code generated by E-Studio and customizing it. This is the updated experiment:

As you see, Feedback now resides under Unreferenced objects, i.e., it doesn’t reside inside a procedure. To achieve this, either delete Feedback from the procedure it already resides in, or, if you haven’t created it yet, drag the FeedbackDisplay button to the background of the E-Prime window. In both cases Feedback will be unreferenced.

There are also two InLines. An InLine is a piece of code (program) that you can write yourself. When you double-click on an InLine, you get an empty page where you can write code. Here is the code you need in AddStats (note the small “copy to clipboard” link at the top):

'Add an observation to the accuracy stats
Feedback.AccStats.AddObservation Stimulus.Acc

'Add an observation to the response time stats
' unless the user did not respond 
If Len(Stimulus.RESP) > 0 Then
	Feedback.RTStats.AddObservation Stimulus.RT
	Feedback.CorrectRTStats.AddObservation Stimulus.RT
End If

Here is the code for ShowFeedback:

'Generate statistics text to be shown
'Note that if you add more text and then see that statistics appear in the wrong places, 
'try changing the numbers in Objects(1) and Objects(2)
Set Feedback_SlideText = CSlideText(Feedback.States.Item("Correct").Objects(1))
Feedback_SlideText.Text = "" & _
	Format$((Feedback.ACCStats.Mean / Feedback.ACCDivisor),Feedback.ACCFormat) & " Correct"
Set Feedback_SlideText = Nothing

Set Feedback_SlideText = CSlideText(Feedback.States.Item("Correct").Objects(2))
Feedback_SlideText.Text = "" & _
	Format$((Feedback.RTStats.Mean / Feedback.RTDivisor), Feedback.RTFormat) & _
	" Seconds Average Response Time"
Set Feedback_SlideText = Nothing


'You only need this part if you want to let the user close Feedback by pressing a key
Feedback.InputMasks.Reset
If Keyboard.GetState() = ebStateOpen Then
	FeedbackEchoClients.RemoveAll
	Feedback.InputMasks.Add Keyboard.CreateInputMask("{ANY}", "", CLng(Feedback.Duration), CLng("1"), ebEndResponseActionTerminate, CLogical("Yes"), "", "", "ResponseMode:All ProcessBackspace:Yes")
End If

' Show the window
Feedback.Run

If you name your feedback and stimulus objects some other names than Feedback and Stimulus, you’ll have to search for Feedback and Stimulus in the code and replace by the respective names you use. You can also customize your ShowFeedback code to modify the feedback text or to disable dismissing the feedback with the keyboard.

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Tags: e-prime