Thread: need help with data calcs & export View Single Post
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Join Date: Dec 2008
bradw is on a distinguished road Posts: 9
need help with data calcs & export, Posted January 5th, 2009 #1
Hi folks,

I'm new to the forum and Superlab and need some help. I have 'inherited' data from an Emotional Stroop task that I wish to clean, transform and then merge in SPSS.

For each participant, an introduction screen is first presented, followed by a practice/instruction screen, then 10 practice trials (using a subset of stimuli presented in the actual trials), another instruction 9'are you ready?') screen, then the 48 actual trials (4 stimulus word types, each with 6 words, and 4 corresponding control-neutral word sets of 6 words each, presented in a randomized order for each participant, but with each word assigned and recorded as a unique Trial Number across all participants... e.g., the word "worried" = trial no. 14, "tense"= trial 32, etc).

The data files for each participant display as follows when I open them in Excel. (I've deleted several irrelevant columns and rows for sake of brevity here.) In the data output, there are several different variables that are recorded in the first column (participant ID -- in this case "101W", followed by the task name, date, and trial name), only one of which I care about (ID), while the other variables of interest each have their own column:

Wed Jan 1, 12:33:00 2008

Trial Name Trial No. Error Code ReactionTime
intro 1 C 561243
practice 2 C 2062
red-worried 14 C 1001 (*this is the first practice trial)
* (9 more practice trial rows -- deleted here)
instructions 3 C 5000
blue-tense 32 E 1205
red-cat 20 C 782
* (46 more actual trials -- deleted here)

I need help coming up with a way (maybe a macros program or two? never used macros before) to do the following:

1) Screen/clean data for each participant:

a) Discard Instructions and Practice Trials (i.e. all Trial rows between the Trial Name “Introduction” row and “Instructions” row).

b) Discard overly fast/slow Trials: (i.e. Trial rows with Reaction Time <100 msec or >3000 msec)

c) Discard Trials with incorrect responses (i.e. Trial rows with Error Code = E)

d) Code as invalid any participant's data containing too many errors (i.e. less than 39 valid actual trials remaining)

2) Compute means to summarize each participant's data & merge into SPSS:

Desired SPSS format:
ID No. MeanRTW1 MeanRTW1cn MeanRTW2 MeanRTW2cn... (8 total summary variables)

Where Mean RTW1=Mean Reaction Time for Type 1 Words: i.e. sum of Reaction Time values for rows with corresponding Trial No. values of 12, 13, 74, 53, 54, and 31, divided by the total number of RT values (6, or less if trials were discarded)

Mean RTW1cn= Mean Reaction Time for Type 1 Control Words (i.e., corresponding to trials 58, 38, 39, 40, 80, 81).

Etc. for Word types 3 & 4 and their control word sets (total of 8 variables).

I tried the Superlab Data Viewer but didn't know what I was doing and couldn't find an instruction manual. I'm not sure what version of Superlab this program was written in but I presume it was an earlier one since data collection began in 2005. I would greatly appreciate any assistance you can provide.

Brad W
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