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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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 (317 views, 43.00 KB)
	Reply Like 52
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 (290 views, 23.00 KB)
	Reply Like 56
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 - 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