> I wonder if I can somehow make the number of each item (1-16) appears in the output file.
No, you can't*. However, for data analysis purposes it's just a matter of a simple "recode" operation on the trialcode column.
* Save for actually *naming* your <radiobuttons> elements "1" to "16" (which I would not recommend in general). I.e.,
<surveypage explicitsem1>
/ stimulusframes = [1=arabs; 2=english]
/ questions = [1=hardworking_anchor; 2=
1; 3=lazy_anchor;
4=know_anchor; 5=
2; 6=ignorant_anchor; ...]
[...]
</surveypage>
<radiobuttons
1>
/ caption = ""
/ options = ("", "", "", "", "", "", "")
/ optionvalues = ("3", "2", "1", "0", "-1", "-2", "-3")
/ fontstyle = ("Verdana", -20, true, false, false, false, 5, 0)
/ orientation = horizontal
/ size = (10%, 90%)
/ position = (40, 10)
/ txcolor = (0, 255, 0)
</radiobuttons>
[...]
<radiobuttons
2>
/ caption = ""
/ options = ("", "", "", "", "", "", "")
/ optionvalues = ("3", "2", "1", "0", "-1", "-2", "-3")
/ fontstyle = ("Verdana", -20, true, false, false, false, 5, 0)
/ orientation = horizontal
/ size = (10%, 90%)
/ position = (40, 15)
/ txcolor = (0, 255, 0)
</radiobuttons>