﻿<?xml version="1.0" encoding="UTF-8"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/"><channel><title>Millisecond Forums » Millisecond Forums » Inquisit 4  » randomised location on screen does not work properly</title><generator>InstantForum 2017-1 Final</generator><description>Millisecond Forums</description><link>https://forums.millisecond.com/</link><webMaster>Millisecond Forums</webMaster><lastBuildDate>Fri, 25 Sep 2026 17:33:36 GMT</lastBuildDate><ttl>20</ttl><item><title>randomised location on screen does not work properly</title><link>https://forums.millisecond.com/Topic22669.aspx</link><description>Dear All,&lt;br/&gt;&lt;br/&gt;I have a task that presents two visual stimuli at the same time one above the other. The specific stimulus location should be randomly assigned - at one trial, X should appear above Y, and on the other trial - the other way round.&lt;br/&gt;Below I paste the part that should regulate this, but it doesn't. That means, that on most trials it works fine, but occasionally both X and Y appear in the same location.&amp;nbsp;&lt;br/&gt;&lt;br/&gt;I cannot detect what I did wrong, Please help!&lt;br/&gt;&lt;br/&gt;Robert&lt;br/&gt;&lt;br/&gt;Now I did smth like this:&lt;br/&gt;&lt;br/&gt;&lt;span style="font-size: 10pt;"&gt;&amp;lt;item nonwords&amp;gt;&lt;/span&gt;&lt;br/&gt;/1 = "KADIRGA"&lt;br/&gt;/2 = "LOKANTA"&lt;br/&gt;/3 = "NIJARON"&lt;br/&gt;/4 = "FEVKANI"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item positive_words&amp;gt;&lt;br/&gt;/1 = "miÅoÅÄ"&lt;br/&gt;/2 = "przyjaÅºÅ"&lt;br/&gt;/3 = "uÅcisk"&lt;br/&gt;/4 = "pokÃ³j"&lt;br/&gt;/5 = "radoÅÄ"&lt;br/&gt;/6 = "uÅmiech"&lt;br/&gt;/7 = "kwiaty"&lt;br/&gt;/8 = "muzyka"&lt;br/&gt;/9 = "zabawa"&lt;br/&gt;/10 = "sztuka"&lt;br/&gt;/11= "dobro"&lt;br/&gt;/12= "wakacje"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item negative_words&amp;gt;&lt;br/&gt;/1 = "zÅo"&lt;br/&gt;/2 = "ÅmierÄ"&lt;br/&gt;/3 = "choroba"&lt;br/&gt;/4 = "rak"&lt;br/&gt;/5 = "wrÃ³g"&lt;br/&gt;/6 = "pistolet"&lt;br/&gt;/7 = "wojna"&lt;br/&gt;/8 = "wrÃ³g"&lt;br/&gt;/9 = "przemoc"&lt;br/&gt;/10 = "agresja"&lt;br/&gt;/11 = "nieprzyjaciel"&lt;br/&gt;/12 = "pogarda"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;text fixation&amp;gt;&lt;br/&gt;/ items = ("X")&lt;br/&gt;/ fontstyle = ("Arial", 5.04%, true, false, false, false, 5, 0)&lt;br/&gt;/ txcolor = (220, 20, 60)&lt;br/&gt;&amp;lt;/text&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;text nonwords_pos&amp;gt;&lt;br/&gt; /items = nonwords_pos&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, counter.position.selectedvalue)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt; &lt;br/&gt;&amp;lt;text nonwords_neg&amp;gt;&lt;br/&gt; /items = nonwords_neg&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, counter.position.selectedvalue)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt;&lt;br/&gt; &amp;lt;text positive_words&amp;gt;&lt;br/&gt; /items = positive_words&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, 30)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt; &lt;br/&gt; &amp;lt;text negative_words&amp;gt;&lt;br/&gt; /items = negative_words&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, 30)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt; &lt;br/&gt; &amp;lt;counter position&amp;gt;&lt;br/&gt;/ select = replace&lt;br/&gt;/ selectionrate = always&lt;br/&gt;/ items = (70,30)&lt;br/&gt;&amp;lt;/counter&amp;gt;&lt;br/&gt;&lt;br/&gt;ounter position_affect&amp;gt;&lt;br/&gt;/ select = replacenot(counter.position)&lt;br/&gt;/ selectionrate = always&lt;br/&gt;/ items = (70,30)&lt;br/&gt;&amp;lt;/counter&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item nonwords_pos&amp;gt;&lt;br/&gt;/1 = "KADIRGA"&lt;br/&gt;/2 = "LOKANTA"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item nonwords_neg&amp;gt;&lt;br/&gt;/1 = "NIJARON"&lt;br/&gt;/2 = "FEVKANI"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_pos&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.positive_words.vposition = 30;if(counter.position.selectedvalue == 30) text.positive_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_pos ; 200 = positive_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("j")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_posneg&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.negative_words.vposition = 30; if(counter.position.selectedvalue == 30) text.negative_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_pos ; 200 = negative_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("f")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_neg&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.negative_words.vposition = 30; if(counter.position.selectedvalue == 30) text.negative_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_neg ; 200 = negative_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("f")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_negpos&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.positive_words.vposition = 30; if(counter.position.selectedvalue == 30) text.positive_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_neg ; 200 = positive_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("f")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;block condi&amp;gt;&lt;br/&gt;/ preinstructions = (instrukcja_klasyfikacja)&lt;br/&gt;/ trials = [1-40 = noreplace(non_pos, non_pos, non_pos, non_pos, non_pos, non_pos, non_pos, non_pos, non_posneg, non_posneg,&lt;br/&gt;non_neg, non_neg, non_negpos, non_negpos,non_negpos,non_negpos,non_negpos,non_negpos,non_negpos)]&lt;br/&gt;&amp;lt;/block&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;text errortext&amp;gt;&lt;br/&gt;/ items = ("XXX")&lt;br/&gt;/ fontstyle = ("Arial Unicode MS", 2.00%, false, false, false, false, 5, 0)&lt;br/&gt;/ color = crimson&lt;br/&gt;&amp;lt;/text&amp;gt;&lt;br/&gt;&lt;br/&gt;</description><pubDate>Thu, 12 Oct 2017 12:54:06 GMT</pubDate><dc:creator>RBalas</dc:creator></item><item><title>RE: randomised location on screen does not work properly</title><link>https://forums.millisecond.com/Topic22681.aspx</link><description>&lt;div data-id="22673" class="if-quote-wrapper" unselectable="on" data-guid="1507838035333"&gt;&lt;a class="quote-para" unselectable="on" style="display: none;" href="#" data-id="22673" title="Move Cursor Below" contenteditable="false"&gt;&lt;span unselectable="on"&gt;+&lt;/span&gt;&lt;/a&gt;&lt;a class="quote-delete" unselectable="on" style="display: none;" href="#" data-id="22673" title="Delete Quote" contenteditable="false"&gt;&lt;span unselectable="on"&gt;x&lt;/span&gt;&lt;/a&gt;&lt;span unselectable="on" class="quote-markup"&gt;[quote]&lt;/span&gt;&lt;div unselectable="on" class="if-quote-header" contenteditable="false"&gt;&lt;div unselectable="on" class="if-quote-toggle-wrapper"&gt;&lt;a class="if-quote-toggle quote-link" href="#" data-id="22673" title=" "&gt;&lt;/a&gt;&lt;/div&gt;&lt;span unselectable="on" class="quote-markup"&gt;[b]&lt;/span&gt;Dave - Wednesday, October 11, 2017&lt;span unselectable="on" class="quote-markup"&gt;[/b]&lt;/span&gt;&lt;/div&gt;&lt;div class="if-quote-message if-quote-message-22673"&gt;&lt;div class="if-quote-message-margin"&gt;&lt;div data-id="22669" class="if-quote-wrapper" unselectable="on" data-guid="1507838035333"&gt;&lt;a class="quote-para" unselectable="on" style="display: none;" href="#" data-id="22669" title="Move Cursor Below" contenteditable="false"&gt;&lt;span unselectable="on"&gt;+&lt;/span&gt;&lt;/a&gt;&lt;a class="quote-delete" unselectable="on" style="display: none;" href="#" data-id="22669" title="Delete Quote" contenteditable="false"&gt;&lt;span unselectable="on"&gt;x&lt;/span&gt;&lt;/a&gt;&lt;span unselectable="on" class="quote-markup"&gt;[quote]&lt;/span&gt;&lt;div unselectable="on" class="if-quote-header" contenteditable="false"&gt;&lt;div unselectable="on" class="if-quote-toggle-wrapper"&gt;&lt;a class="if-quote-toggle quote-link" href="#" data-id="22669" title=" "&gt;&lt;/a&gt;&lt;/div&gt;&lt;span unselectable="on" class="quote-markup"&gt;[b]&lt;/span&gt;RBalas - Wednesday, October 11, 2017&lt;span unselectable="on" class="quote-markup"&gt;[/b]&lt;/span&gt;&lt;/div&gt;&lt;div class="if-quote-message if-quote-message-22669"&gt;&lt;div class="if-quote-message-margin"&gt;Dear All,&lt;br/&gt;&lt;br/&gt;I have a task that presents two visual stimuli at the same time one above the other. The specific stimulus location should be randomly assigned - at one trial, X should appear above Y, and on the other trial - the other way round.&lt;br/&gt;Below I paste the part that should regulate this, but it doesn't. That means, that on most trials it works fine, but occasionally both X and Y appear in the same location.&amp;nbsp;&lt;br/&gt;&lt;br/&gt;I cannot detect what I did wrong, Please help!&lt;br/&gt;&lt;br/&gt;Robert&lt;br/&gt;&lt;br/&gt;Now I did smth like this:&lt;br/&gt;&lt;br/&gt;&lt;span style="font-size: 10pt;"&gt;&amp;lt;item nonwords&amp;gt;&lt;/span&gt;&lt;br/&gt;/1 = "KADIRGA"&lt;br/&gt;/2 = "LOKANTA"&lt;br/&gt;/3 = "NIJARON"&lt;br/&gt;/4 = "FEVKANI"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item positive_words&amp;gt;&lt;br/&gt;/1 = "miÅoÅÄ"&lt;br/&gt;/2 = "przyjaÅºÅ"&lt;br/&gt;/3 = "uÅcisk"&lt;br/&gt;/4 = "pokÃ³j"&lt;br/&gt;/5 = "radoÅÄ"&lt;br/&gt;/6 = "uÅmiech"&lt;br/&gt;/7 = "kwiaty"&lt;br/&gt;/8 = "muzyka"&lt;br/&gt;/9 = "zabawa"&lt;br/&gt;/10 = "sztuka"&lt;br/&gt;/11= "dobro"&lt;br/&gt;/12= "wakacje"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item negative_words&amp;gt;&lt;br/&gt;/1 = "zÅo"&lt;br/&gt;/2 = "ÅmierÄ"&lt;br/&gt;/3 = "choroba"&lt;br/&gt;/4 = "rak"&lt;br/&gt;/5 = "wrÃ³g"&lt;br/&gt;/6 = "pistolet"&lt;br/&gt;/7 = "wojna"&lt;br/&gt;/8 = "wrÃ³g"&lt;br/&gt;/9 = "przemoc"&lt;br/&gt;/10 = "agresja"&lt;br/&gt;/11 = "nieprzyjaciel"&lt;br/&gt;/12 = "pogarda"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;text fixation&amp;gt;&lt;br/&gt;/ items = ("X")&lt;br/&gt;/ fontstyle = ("Arial", 5.04%, true, false, false, false, 5, 0)&lt;br/&gt;/ txcolor = (220, 20, 60)&lt;br/&gt;&amp;lt;/text&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;text nonwords_pos&amp;gt;&lt;br/&gt; /items = nonwords_pos&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, counter.position.selectedvalue)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt; &lt;br/&gt;&amp;lt;text nonwords_neg&amp;gt;&lt;br/&gt; /items = nonwords_neg&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, counter.position.selectedvalue)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt;&lt;br/&gt; &amp;lt;text positive_words&amp;gt;&lt;br/&gt; /items = positive_words&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, 30)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt; &lt;br/&gt; &amp;lt;text negative_words&amp;gt;&lt;br/&gt; /items = negative_words&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, 30)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt; &lt;br/&gt; &amp;lt;counter position&amp;gt;&lt;br/&gt;/ select = replace&lt;br/&gt;/ selectionrate = always&lt;br/&gt;/ items = (70,30)&lt;br/&gt;&amp;lt;/counter&amp;gt;&lt;br/&gt;&lt;br/&gt;ounter position_affect&amp;gt;&lt;br/&gt;/ select = replacenot(counter.position)&lt;br/&gt;/ selectionrate = always&lt;br/&gt;/ items = (70,30)&lt;br/&gt;&amp;lt;/counter&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item nonwords_pos&amp;gt;&lt;br/&gt;/1 = "KADIRGA"&lt;br/&gt;/2 = "LOKANTA"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item nonwords_neg&amp;gt;&lt;br/&gt;/1 = "NIJARON"&lt;br/&gt;/2 = "FEVKANI"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_pos&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.positive_words.vposition = 30;if(counter.position.selectedvalue == 30) text.positive_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_pos ; 200 = positive_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("j")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_posneg&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.negative_words.vposition = 30; if(counter.position.selectedvalue == 30) text.negative_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_pos ; 200 = negative_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("f")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_neg&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.negative_words.vposition = 30; if(counter.position.selectedvalue == 30) text.negative_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_neg ; 200 = negative_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("f")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_negpos&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.positive_words.vposition = 30; if(counter.position.selectedvalue == 30) text.positive_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_neg ; 200 = positive_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("f")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;block condi&amp;gt;&lt;br/&gt;/ preinstructions = (instrukcja_klasyfikacja)&lt;br/&gt;/ trials = [1-40 = noreplace(non_pos, non_pos, non_pos, non_pos, non_pos, non_pos, non_pos, non_pos, non_posneg, non_posneg,&lt;br/&gt;non_neg, non_neg, non_negpos, non_negpos,non_negpos,non_negpos,non_negpos,non_negpos,non_negpos)]&lt;br/&gt;&amp;lt;/block&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;text errortext&amp;gt;&lt;br/&gt;/ items = ("XXX")&lt;br/&gt;/ fontstyle = ("Arial Unicode MS", 2.00%, false, false, false, false, 5, 0)&lt;br/&gt;/ color = crimson&lt;br/&gt;&amp;lt;/text&amp;gt;&lt;br/&gt;&lt;br/&gt;&lt;a class="if-quote-goto quote-link" href="#" data-id="22669"&gt;&lt;span class="goto"&gt;&lt;/span&gt;&lt;/a&gt;&lt;/div&gt;&lt;/div&gt;&lt;span class="quote-markup"&gt;[/quote]&lt;/span&gt;&lt;/div&gt;&lt;br/&gt;You are oversampling your position &amp;lt;counter&amp;gt;. The selectedvalue property performs a selection from the counter; the counters are set to selectionrate=always. Thus, a selection occurs every time you use it. In other words, you are selecting as many as three times from a given &amp;lt;counter&amp;gt;, per your references to selectedvalue in your /ontrialbegin logic and _additionally_ per the references in the stimuli's /position attributes. It actually does not make sense to use /selectionrate=always in your case. As far as I can see, you want one sample from the counter per trial. Thus you can simply use /selectionrate=trial and your problem should go away.&lt;br/&gt;&lt;br/&gt;&amp;lt;counter position&amp;gt;&lt;br/&gt;/ select = replace&lt;br/&gt;/ selectionrate = trial&lt;br/&gt;/ items = (70,30)&lt;br/&gt;&amp;lt;/counter&amp;gt;&lt;br/&gt;&lt;a class="if-quote-goto quote-link" href="#" data-id="22673"&gt;&lt;span class="goto"&gt;&lt;/span&gt;&lt;/a&gt;&lt;/div&gt;&lt;/div&gt;&lt;span class="quote-markup"&gt;[/quote]&lt;/span&gt;&lt;/div&gt;&lt;br/&gt;Dave,&lt;br/&gt;&lt;br/&gt;Once again - you saved my... :)&lt;br/&gt;&lt;br/&gt;thanks!&lt;br/&gt;&lt;br/&gt;Robert</description><pubDate>Thu, 12 Oct 2017 12:54:06 GMT</pubDate><dc:creator>RBalas</dc:creator></item><item><title>RE: randomised location on screen does not work properly</title><link>https://forums.millisecond.com/Topic22673.aspx</link><description>&lt;div data-id="22669" class="if-quote-wrapper" unselectable="on" data-guid="1507741165404"&gt;&lt;a class="quote-para" unselectable="on" style="display: none;" href="#" data-id="22669" title="Move Cursor Below" contenteditable="false"&gt;&lt;span unselectable="on"&gt;+&lt;/span&gt;&lt;/a&gt;&lt;a class="quote-delete" unselectable="on" style="display: none;" href="#" data-id="22669" title="Delete Quote" contenteditable="false"&gt;&lt;span unselectable="on"&gt;x&lt;/span&gt;&lt;/a&gt;&lt;span unselectable="on" class="quote-markup"&gt;[quote]&lt;/span&gt;&lt;div unselectable="on" class="if-quote-header" contenteditable="false"&gt;&lt;div unselectable="on" class="if-quote-toggle-wrapper"&gt;&lt;a class="if-quote-toggle quote-link" href="#" data-id="22669" title=" "&gt;&lt;/a&gt;&lt;/div&gt;&lt;span unselectable="on" class="quote-markup"&gt;[b]&lt;/span&gt;RBalas - Wednesday, October 11, 2017&lt;span unselectable="on" class="quote-markup"&gt;[/b]&lt;/span&gt;&lt;/div&gt;&lt;div class="if-quote-message if-quote-message-22669"&gt;&lt;div class="if-quote-message-margin"&gt;Dear All,&lt;br/&gt;&lt;br/&gt;I have a task that presents two visual stimuli at the same time one above the other. The specific stimulus location should be randomly assigned - at one trial, X should appear above Y, and on the other trial - the other way round.&lt;br/&gt;Below I paste the part that should regulate this, but it doesn't. That means, that on most trials it works fine, but occasionally both X and Y appear in the same location.&amp;nbsp;&lt;br/&gt;&lt;br/&gt;I cannot detect what I did wrong, Please help!&lt;br/&gt;&lt;br/&gt;Robert&lt;br/&gt;&lt;br/&gt;Now I did smth like this:&lt;br/&gt;&lt;br/&gt;&lt;span style="font-size: 10pt;"&gt;&amp;lt;item nonwords&amp;gt;&lt;/span&gt;&lt;br/&gt;/1 = "KADIRGA"&lt;br/&gt;/2 = "LOKANTA"&lt;br/&gt;/3 = "NIJARON"&lt;br/&gt;/4 = "FEVKANI"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item positive_words&amp;gt;&lt;br/&gt;/1 = "miÅoÅÄ"&lt;br/&gt;/2 = "przyjaÅºÅ"&lt;br/&gt;/3 = "uÅcisk"&lt;br/&gt;/4 = "pokÃ³j"&lt;br/&gt;/5 = "radoÅÄ"&lt;br/&gt;/6 = "uÅmiech"&lt;br/&gt;/7 = "kwiaty"&lt;br/&gt;/8 = "muzyka"&lt;br/&gt;/9 = "zabawa"&lt;br/&gt;/10 = "sztuka"&lt;br/&gt;/11= "dobro"&lt;br/&gt;/12= "wakacje"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item negative_words&amp;gt;&lt;br/&gt;/1 = "zÅo"&lt;br/&gt;/2 = "ÅmierÄ"&lt;br/&gt;/3 = "choroba"&lt;br/&gt;/4 = "rak"&lt;br/&gt;/5 = "wrÃ³g"&lt;br/&gt;/6 = "pistolet"&lt;br/&gt;/7 = "wojna"&lt;br/&gt;/8 = "wrÃ³g"&lt;br/&gt;/9 = "przemoc"&lt;br/&gt;/10 = "agresja"&lt;br/&gt;/11 = "nieprzyjaciel"&lt;br/&gt;/12 = "pogarda"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;text fixation&amp;gt;&lt;br/&gt;/ items = ("X")&lt;br/&gt;/ fontstyle = ("Arial", 5.04%, true, false, false, false, 5, 0)&lt;br/&gt;/ txcolor = (220, 20, 60)&lt;br/&gt;&amp;lt;/text&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;text nonwords_pos&amp;gt;&lt;br/&gt; /items = nonwords_pos&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, counter.position.selectedvalue)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt; &lt;br/&gt;&amp;lt;text nonwords_neg&amp;gt;&lt;br/&gt; /items = nonwords_neg&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, counter.position.selectedvalue)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt;&lt;br/&gt; &amp;lt;text positive_words&amp;gt;&lt;br/&gt; /items = positive_words&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, 30)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt; &lt;br/&gt; &amp;lt;text negative_words&amp;gt;&lt;br/&gt; /items = negative_words&lt;br/&gt; /select = noreplace&lt;br/&gt; /position = (50, 30)&lt;br/&gt; /txcolor = (255, 0, 0)&lt;br/&gt; &amp;lt;/text&amp;gt;&lt;br/&gt; &lt;br/&gt; &amp;lt;counter position&amp;gt;&lt;br/&gt;/ select = replace&lt;br/&gt;/ selectionrate = always&lt;br/&gt;/ items = (70,30)&lt;br/&gt;&amp;lt;/counter&amp;gt;&lt;br/&gt;&lt;br/&gt;ounter position_affect&amp;gt;&lt;br/&gt;/ select = replacenot(counter.position)&lt;br/&gt;/ selectionrate = always&lt;br/&gt;/ items = (70,30)&lt;br/&gt;&amp;lt;/counter&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item nonwords_pos&amp;gt;&lt;br/&gt;/1 = "KADIRGA"&lt;br/&gt;/2 = "LOKANTA"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;item nonwords_neg&amp;gt;&lt;br/&gt;/1 = "NIJARON"&lt;br/&gt;/2 = "FEVKANI"&lt;br/&gt;&amp;lt;/item&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_pos&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.positive_words.vposition = 30;if(counter.position.selectedvalue == 30) text.positive_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_pos ; 200 = positive_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("j")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_posneg&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.negative_words.vposition = 30; if(counter.position.selectedvalue == 30) text.negative_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_pos ; 200 = negative_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("f")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_neg&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.negative_words.vposition = 30; if(counter.position.selectedvalue == 30) text.negative_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_neg ; 200 = negative_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("f")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;trial non_negpos&amp;gt;&lt;br/&gt;/ontrialbegin = [if(counter.position.selectedvalue == 70) text.positive_words.vposition = 30; if(counter.position.selectedvalue == 30) text.positive_words.vposition = 70 ]&lt;br/&gt;/ pretrialpause = 1000]&lt;br/&gt;/ pretrialpause = 1000&lt;br/&gt;/ stimulustimes = [1 = fixation; 50 = nonwords_neg ; 200 = positive_words]&lt;br/&gt;/ validresponse = ("j", "f")&lt;br/&gt;/ correctresponse = ("f")&lt;br/&gt;/ errormessage = (errortext,1500)&lt;br/&gt;&amp;lt;/trial&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;block condi&amp;gt;&lt;br/&gt;/ preinstructions = (instrukcja_klasyfikacja)&lt;br/&gt;/ trials = [1-40 = noreplace(non_pos, non_pos, non_pos, non_pos, non_pos, non_pos, non_pos, non_pos, non_posneg, non_posneg,&lt;br/&gt;non_neg, non_neg, non_negpos, non_negpos,non_negpos,non_negpos,non_negpos,non_negpos,non_negpos)]&lt;br/&gt;&amp;lt;/block&amp;gt;&lt;br/&gt;&lt;br/&gt;&amp;lt;text errortext&amp;gt;&lt;br/&gt;/ items = ("XXX")&lt;br/&gt;/ fontstyle = ("Arial Unicode MS", 2.00%, false, false, false, false, 5, 0)&lt;br/&gt;/ color = crimson&lt;br/&gt;&amp;lt;/text&amp;gt;&lt;br/&gt;&lt;br/&gt;&lt;a class="if-quote-goto quote-link" href="#" data-id="22669"&gt;&lt;span class="goto"&gt;&lt;/span&gt;&lt;/a&gt;&lt;/div&gt;&lt;/div&gt;&lt;span class="quote-markup"&gt;[/quote]&lt;/span&gt;&lt;/div&gt;&lt;br/&gt;You are oversampling your position &amp;lt;counter&amp;gt;. The selectedvalue property performs a selection from the counter; the counters are set to selectionrate=always. Thus, a selection occurs every time you use it. In other words, you are selecting as many as three times from a given &amp;lt;counter&amp;gt;, per your references to selectedvalue in your /ontrialbegin logic and _additionally_ per the references in the stimuli's /position attributes. It actually does not make sense to use /selectionrate=always in your case. As far as I can see, you want one sample from the counter per trial. Thus you can simply use /selectionrate=trial and your problem should go away.&lt;br/&gt;&lt;br/&gt;&amp;lt;counter position&amp;gt;&lt;br/&gt;/ select = replace&lt;br/&gt;/ selectionrate = trial&lt;br/&gt;/ items = (70,30)&lt;br/&gt;&amp;lt;/counter&amp;gt;&lt;br/&gt;</description><pubDate>Wed, 11 Oct 2017 10:08:24 GMT</pubDate><dc:creator>Dave</dc:creator></item></channel></rss>