Millisecond Forums

Change AAT script Wiers 2009 4 practice items

https://www.millisecond.com/forums/Topic29502.aspx

By poleraze - 7/29/2020

Hello everyone,

Im using the uploaded AAT script from Wiers et al. 2009 .
In our testing we have to groups healthy and unhealthy food. Every eatable object has an uneatable match that looks similar.
People will be instructed to pull eatable items and push not eatable items and we will look at the difference in RT for healthy and unheqlthy snacks.
The problem now is that i need 4 practice items but i dont understand the value picking. I thought i could write that the value should be greater than 2 and for the other group smaller than 2
so i changed
=> / ontrialbegin = [values.selectpracticepicture = 1 ]
to
/ ontrialbegin = [values.selectpracticepicture <= 2 ]
and
/ ontrialbegin = [values.selectpracticepicture >= 2 ]
but that doesnt work.
Why? (Question1)

My next idea was to creat a list and copy the aat (target) selection. But then i have to change the whole script...
Question 2 = How do i tell a list from which itempool it has to select its items? I have two, target and practice.

Question 3 Does anyone have a solution that will help me ?

Thank you all





By Dave - 7/29/2020

poleraze - 7/29/2020
Hello everyone,

Im using the uploaded AAT script from Wiers et al. 2009 .
In our testing we have to groups healthy and unhealthy food. Every eatable object has an uneatable match that looks similar.
People will be instructed to pull eatable items and push not eatable items and we will look at the difference in RT for healthy and unheqlthy snacks.
The problem now is that i need 4 practice items but i dont understand the value picking. I thought i could write that the value should be greater than 2 and for the other group smaller than 2
so i changed
=> / ontrialbegin = [values.selectpracticepicture = 1 ]
to
/ ontrialbegin = [values.selectpracticepicture <= 2 ]
and
/ ontrialbegin = [values.selectpracticepicture >= 2 ]
but that doesnt work.
Why? (Question1)

My next idea was to creat a list and copy the aat (target) selection. But then i have to change the whole script...
Question 2 = How do i tell a list from which itempool it has to select its items? I have two, target and practice.

Question 3 Does anyone have a solution that will help me ?

Thank you all






values.selectpracticepicture determines which practice item number is displayed. It makes no sense to try to set it to >= 2. That's not an item number.

NOTE:
picture.practicetarget selects the target via
values.selectpracticepicture (this value is set in the
practice trials, see below)

<picture practicetarget>
/ items = practicestimuli
/ select = values.selectpracticepicture
/ position = (50%, 50%)
/ size = (100%, 100%)
/ erase = false
</picture>

<item practicestimuli>
/1 = "healthy_aprikosen_p1.png"
/2 = "unhealthy_lindt_p2.png"
/3 = "match_healthy_lavera_p1.jpg"
/4 = "match_unhealthy_oldspice_p2.jpg"
</item>

By Dave - 7/29/2020

Dave - 7/29/2020
poleraze - 7/29/2020
Hello everyone,

Im using the uploaded AAT script from Wiers et al. 2009 .
In our testing we have to groups healthy and unhealthy food. Every eatable object has an uneatable match that looks similar.
People will be instructed to pull eatable items and push not eatable items and we will look at the difference in RT for healthy and unheqlthy snacks.
The problem now is that i need 4 practice items but i dont understand the value picking. I thought i could write that the value should be greater than 2 and for the other group smaller than 2
so i changed
=> / ontrialbegin = [values.selectpracticepicture = 1 ]
to
/ ontrialbegin = [values.selectpracticepicture <= 2 ]
and
/ ontrialbegin = [values.selectpracticepicture >= 2 ]
but that doesnt work.
Why? (Question1)

My next idea was to creat a list and copy the aat (target) selection. But then i have to change the whole script...
Question 2 = How do i tell a list from which itempool it has to select its items? I have two, target and practice.

Question 3 Does anyone have a solution that will help me ?

Thank you all






values.selectpracticepicture determines which practice item number is displayed. It makes no sense to try to set it to >= 2. That's not an item number.

NOTE:
picture.practicetarget selects the target via
values.selectpracticepicture (this value is set in the
practice trials, see below)

<picture practicetarget>
/ items = practicestimuli
/ select = values.selectpracticepicture
/ position = (50%, 50%)
/ size = (100%, 100%)
/ erase = false
</picture>

<item practicestimuli>
/1 = "healthy_aprikosen_p1.png"
/2 = "unhealthy_lindt_p2.png"
/3 = "match_healthy_lavera_p1.jpg"
/4 = "match_unhealthy_oldspice_p2.jpg"
</item>


If I'm understanding your script correctly (I might not), then items 1 and 2 are the "essbar" items and should be presented by practicetrial_Essbar, while items 3 and 4 are the "nicht essbar" items and should be presented by trial practicetrial_Nicht_Essbar.

If so, you need two lists

<list practice_essbaritems>
/ items = (1,2)
</list>

<list practice_nicht_essbaritems>
/ items = (3,4)
</list>

and sample the item numbers from the appropriate list in the two trial elements:

<trial practicetrial_Essbar>
/ontrialbegin = [values.targetformat = "Essbar"]
/ ontrialbegin = [values.selectpracticepicture = list.practice_essbaritems.nextvalue;]
...
</trial>

<trial practicetrial_Nicht_Essbar>
/ontrialbegin = [values.targetformat = "Nicht-Essbar"]
/ontrialbegin = [values.starttime = script.elapsedtime; values.endtime = 0]
/ ontrialbegin = [values.repeat = 0]
/ ontrialbegin = [values.selectpracticepicture = list.practice_nicht_essbaritems.nextvalue;]
...
</trial>


By poleraze - 7/29/2020

Thank you it works. Can you explain to me why he slects from the practice itempool?
By Dave - 7/29/2020

poleraze - 7/29/2020
Thank you it works. Can you explain to me why he slects from the practice itempool?

I don't understand the question. The practice trials display the practice picture element, and values.selectpracticepicture, the value you're setting in the practice trials, determines the item.