Unbalanced presentation of pictures in the Dot Probe

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Unbalanced presentation of pictures in the Dot Probe

Unbalanced presentation of pictures in the Dot Probe

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Dave	Dave posted 6 Years Ago ANSWER Post Details Share Post
Group: Administrators Posts: 13K, Visits: 104K	+x alexa - Tuesday, February 27, 2018 +x Dave - Monday, February 26, 2018 +x alexa - Monday, February 26, 2018 Hello there, I have a question concercing the DotProbe. I modified the DotProbe-script (see attachment). Now I conducted a pretest with the testmonkey (10 times/"participants"). Every participant had 10 pratice trials followed by 160 „real“ trials. The real trials were as followed: 20 high-caloric pictures paired with animals/plants and 20 low-caloric pictures, also paired with animals/plants (40 DP-trials * 4 (left/right and probe/noprobe) = 160 trials). Thus every picture has to be presented 4 times. Now I have analyzed the data and I saw that some pictures are presented more than 40 times (10 participants 4), especially high-caloric pictures, but low-caloric pictures were presented less than 40 times. The practice-block works perfectly... I am wondering why? There has to be an error in my syntax but I don't find it. It would be really nice if someone could help me out. Thanks a lot, Alexa Not seeing any obvious issue or syntax error in the script. I'm also not seeing any image selected more or less than 4 times (see attached data file from one test run, getting the exact same result in other test runs). Can you attach a raw data file that shows the imbalance? Thank you very much for you help! I have looked at your raw data and everything is a exptected... This is a little bit weird. I just have used the testmonkey again and everything works perfectly. I am very sorry, but a possible explanation might be that I have made changes in the syntax yesterday (I remember this, see below), but didn't save it before using the testmonkey. <blockImageDotProbeTask> /onblockbegin = [values.task = 2] /trials = [1-160 = noreplace(highcaloric, highcaloric, Filler)] </block> to: <block ImageDotProbeTask> /onblockbegin = [values.task = 2] /trials = [1-160 = noreplace(highcaloric, Filler)] </block> I am very sorry for the inconvenience (but reassured that everything works fine now)! Alexa Ah, yes, this makes sense. <blockImageDotProbeTask> /onblockbegin = [values.task = 2] /trials = [1-160 = noreplace(highcaloric, highcaloric, Filler*)] </block> would result in 106 to 107 "highcaloric" trials out of the 160, and the rest being "filler" trials. That would explain the imbalance you observed initially.
	Reply Like 55
alexa	alexa posted 6 Years Ago ANSWER Post Details Share Post
Group: Forum Members Posts: 27, Visits: 78	+x Dave - Monday, February 26, 2018 +x alexa - Monday, February 26, 2018 Hello there, I have a question concercing the DotProbe. I modified the DotProbe-script (see attachment). Now I conducted a pretest with the testmonkey (10 times/"participants"). Every participant had 10 pratice trials followed by 160 „real“ trials. The real trials were as followed: 20 high-caloric pictures paired with animals/plants and 20 low-caloric pictures, also paired with animals/plants (40 DP-trials * 4 (left/right and probe/noprobe) = 160 trials). Thus every picture has to be presented 4 times. Now I have analyzed the data and I saw that some pictures are presented more than 40 times (10 participants *4), especially high-caloric pictures, but low-caloric pictures were presented less than 40 times. The practice-block works perfectly... I am wondering why? There has to be an error in my syntax but I don't find it. It would be really nice if someone could help me out. Thanks a lot, Alexa Not seeing any obvious issue or syntax error in the script. I'm also not seeing any image selected more or less than 4 times (see attached data file from one test run, getting the exact same result in other test runs). Can you attach a raw data file that shows the imbalance? Thank you very much for you help! I have looked at your raw data and everything is a exptected... This is a little bit weird. I just have used the testmonkey again and everything works perfectly. I am very sorry, but a possible explanation might be that I have made changes in the syntax yesterday (I remember this, see below), but didn't save it before using the testmonkey. <blockImageDotProbeTask> /onblockbegin = [values.task = 2] /trials = [1-160 = noreplace(highcaloric, highcaloric, Filler)] </block> to: <block ImageDotProbeTask> /onblockbegin = [values.task = 2] /trials = [1-160 = noreplace(highcaloric, Filler)] </block> I am very sorry for the inconvenience (but reassured that everything works fine now)! Alexa
	Reply Like 58
Dave	Dave posted 6 Years Ago ANSWER Post Details Share Post
Group: Administrators Posts: 13K, Visits: 104K	+x alexa - Monday, February 26, 2018 Hello there, I have a question concercing the DotProbe. I modified the DotProbe-script (see attachment). Now I conducted a pretest with the testmonkey (10 times/"participants"). Every participant had 10 pratice trials followed by 160 „real“ trials. The real trials were as followed: 20 high-caloric pictures paired with animals/plants and 20 low-caloric pictures, also paired with animals/plants (40 DP-trials * 4 (left/right and probe/noprobe) = 160 trials). Thus every picture has to be presented 4 times. Now I have analyzed the data and I saw that some pictures are presented more than 40 times (10 participants *4), especially high-caloric pictures, but low-caloric pictures were presented less than 40 times. The practice-block works perfectly... I am wondering why? There has to be an error in my syntax but I don't find it. It would be really nice if someone could help me out. Thanks a lot, Alexa Not seeing any obvious issue or syntax error in the script. I'm also not seeing any image selected more or less than 4 times (see attached data file from one test run, getting the exact same result in other test runs). Can you attach a raw data file that shows the imbalance? Attachments highcaloricDotProbe_rawdata_1_2018-02-26-17-09-43-067.iqdat (291 views, 23.00 KB)
	Reply Like 56
alexa	alexa posted 6 Years Ago Topic Details Share Topic
Group: Forum Members Posts: 27, Visits: 78	Hello there, I have a question concercing the DotProbe. I modified the DotProbe-script (see attachment). Now I conducted a pretest with the testmonkey (10 times/"participants"). Every participant had 10 pratice trials followed by 160 „real“ trials. The real trials were as followed: 20 high-caloric pictures paired with animals/plants and 20 low-caloric pictures, also paired with animals/plants (40 DP-trials * 4 (left/right and probe/noprobe) = 160 trials). Thus every picture has to be presented 4 times. Now I have analyzed the data and I saw that some pictures are presented more than 40 times (10 participants *4), especially high-caloric pictures, but low-caloric pictures were presented less than 40 times. The practice-block works perfectly... I am wondering why? There has to be an error in my syntax but I don't find it. It would be really nice if someone could help me out. Thanks a lot, Alexa Attachments DotProbe_final_testmonkey.iqx (318 views, 43.00 KB)
	Reply Like 52