DATA PREPARATION Before you Begin 1. On the google drive, open the “Smoking Pilot Eyedata Processing” document and place your initials in the “processed” column of a participant’s data. 2. On the lab server, in the RAW Subject Data folder, copy your participant’s Eye tracking data and save it as “Subjectnumber_processed” in EyedataàProcessed Subject Data
Open ASL Results Plus and Add Your Subject’s Data 1. On the lab server, in àEye DataàSmoking Study Eyedata Analysis 1.23.15, open the “Smoking Study Analysis” file. 2. Click FileàOpen Participant File(s), and select your participant’s PROCESSED eye data file from Eye DataàProcessed Subject Data Your participant’s data will be added on the left side of the ASL project window, under “Participant Files.”
A. Parse Event into Fixation and Picture Presentation Periods 1. Right click on your subject’s data file name and select “Parse Events”. 2. You will see a pop-‐up box (see image to right). • In the Event Start Condition Section, Select “Specific value(s). • In The Event End Condition Section, Select “Any change in value” • Under Additional Options: Check “Zero Time Origin” and “Use as project default”. 3. In the Start/End values window, type the numbers 129-‐168 and then 250 into the boxes. If they are already there that’s okay; check that none are missing 4. Click “okay.”
Now, under your participant’s project file name, the segment will be divided into 80 events. Every two events constitute one trial in the task. The first event in the pair is the fixation cross period (odd numbered event) and the second event in the pair is the cue picture period (even numbered event). For example, Events 1 and 2 are both part of the first trial. Event 1 is when the participant saw the fixation cross and Event 2 is where the participant saw the cue pictures. Events 3 and 4 are part of the second trial…etc. There are 40 trials total.
B. Find Fixation Sequences and Match AOIs with Picture Pairs Now, you will find all of the fixations in each event. These were periods where participant’s eye movements were stable on the screen (fixating). You will also match Cue Picture Pairs with Areas of Interest. 1. Right click on your participant’s file name and select “Find Fixation Sequence”. 2. When the “Fixation Detection Criteria” box appears, click the “Advanced Configuration” button. a. Leave the default settings as-‐is. b. Make sure that under Eyetracker Units/Degree, Horizontal is 7.399 and Vertical is 9.684. c. Click “Okay” 3. As the program finds fixations, you may see some error boxes like this: This simply means that there are no fixations in that particular segment of data (could be due to poor pupil recognition or to the participant’s simply not having fixated during that period). Click “okay” and the program will continue processing the data. At the end of the “finding fixations” period, you may see a popup like this:
This is a list of all of the Events in which ASL Results couldn’t find any fixations. If you do not have one of these popups, that’s okay—the “AOI Sets and/or Background Correspondences” box will open immediately (see step 6).
4. If there is an Error Messages Box, click “Export” and save this information as “subject_number_Error Messages” on the lab server in “Processed Data Excel Sheets.” 5. If there is an Error Messages Box, write “Exclude Event #, NO Fixations” in the google drive processing tracking document for any Events that DO NOT have fixations. 6. If applicable, close the Error Messages Box. The “AOI Sets and/or Background Correspondences” box will appear (see below).
7. Select your participant’s Data File Name in Row 1. If another participant’s data file is in the first row, replace it with your participant’s data file. Leave the Data File Name in the rest of the rows blank.
8. In the XDAT column, type the Numbers 129-‐168 and 250. If the numbers are already there that’s okay, check to be sure they’re correct. 9. Match XDAT numbers with the numbers in the AOI Set and Background drop down menus. XDAT, AOI Set, and Background should be the same number in each row. e.g. XDAT: 129, AOI Set: 129, Background: 129 10. Click Okay.
C. Find Percentage of Data Tracked for Each Event This number might be less than 100% because the eye tracker failed to recognize the participant’s pupil, OR because the eye tracker could not find the participant’s corneal reflection. Both pupil recognition and corneal reflection are crucial to gaze tracking with D6 optics. 1. Right click on your participant’s data file name. 2. Select “Calculate/Display Percent of Data Tracked”. 3. Export this data and save it as “[subject number] percent tracked” in the “Processed Data Excel Sheets” folder on the lab server. 4. Click “Close”. 5. Open the saved “Percent Tracked” text file and keep it open on your desktop.
DATA PROCESSING Before you Begin 1. On the google drive, open the “Smoking Pilot Eye data Processing” document and place your initials in the “processed” column of a participant’s data. 2. On the lab server, open the “Eye Data Processing Template” from Smoking Pilot StudyàParticipant DataàEye data 3. Save the template as your subject number (e.g. “301”) in EyedataàProcessed Data Excel Sheets
Exporting and Processing AOI Summary Tables (DO THIS STEP FIRST) A. Export AOI Summaries Text File 1. In ASL, Go to Fileà Export to Text Fileà FixSeq AOI Summaries. 2. First, unselect all subjects. Then select your participant’s file in the pop-‐up box, and click “Okay.” 3. Save your file as “subject number_TextAOIs” in the “Exported and Processed AOI tables” folder on the lab server. E.g. “323_TextAOIs”
B. Open the Text File in Excel 1. Open a new instance of Excel. 2. In Excel, go to FileàOpen 3. Navigate to the “Exported and Processed AOI Tables” folder on the server. Search for “All Files.” 4. Select your subject’s “TextAOIs” file and click “Okay.” 5. Move through the text import wizard. a. On the first screen, choose “Fixed Width” as the Data Type and press “Next”.
b. On the second screen, scroll through the data preview and make sure all of the column breaks are in the correct place. Double-‐click to delete extra column breaks. c. On the third screen, leave the column data format as “General” and click “Finish.”
C. Delete Extra Columns 1. Delete Columns A-‐F. (File, Segmno, Segmname, Eventno, EventName, AOI#) 2. Delete Columns C, E, F, G, H, and J. (% FixCount, %TotalFixDur, AvgFixDur, AvgInterFixFDur, AvgInterFixDeg, FirstFixTime) At the end, you should have AOIName, FixCount, TotalFixDur, AvgPupilDiam, and XDAT. If you don’t, please undo and try again.
D. Reorganize the Data 1. Click and drag to select all of the data. 2. Go to Sort and FilteràCustom Sort 3. In the first row, Sort By: XDAT, on Value, Order: Smallest to Largest 4. Click Add Level 5. In the second level, Sort By: AOINAME, on Value, Order: A-‐Z
E. Check for Missing XDATS 1. Scroll down the xdat column and check that all of the xdat numbers (129-‐168) are present. If any are missing, it’s because there is no data (ASL couldn’t calculate any fixations for that trial). If XDATS are missing, scroll to the first blank row in the excel sheet and enter the XDAT number from your first missing trial in Row E. It is okay to leave all of the other cells in the row blank. Continue adding XDATS in subsequent rows until you have added one XDAT for each AOI. For quick reference: Enter 8 rows for XDATS: 131, 132, 137, 138 Enter 7 rows for all other XDATs When you have finished, repeat step D.
F. Delete Extra Data Rows from Fixation Cross Period 1. Delete all the rows with XDAT 250 (in the F column). These will all be at the bottom.
G. Copy and Paste Data into Excel Template 1. Scan the XDAT column. XDATS should be in order from smallest to largest (129-‐168). 2. Scan the AOIName column. Cue/Neutral picture AOI’s should be in order from 1-‐20. E.g. XDAT 129 should be with cue 1 and neutral 1; XDAT 131 should be with Cue 2 and Neutral 2; etc.. If cue pairs are not in order from 1-‐20, Stop Processing and let Laura know immediately. 3. Go to FileàSave As and save the reorganized data file as an Excel Document in the “Exported and Processed AOI Tables” folder. Name your file “subjectnumber_Excel AOIs” 4. Click and drag in cell B2 to copy the all of the data from columns B, C, and D. Paste this data into your subject’s Processed Data Excel template in the AOI Summary Tables tab. DO NOT enter any data into the “Percent of time fixated” boxes. 5. Check to be sure that you copied and pasted the data correctly. 6. Enter “-‐9999” in any blank cells (blank rows from when you manually entered missing XDATS). 7. Save your subject’s Processed Data Excel Sheet.
Renaming Trials, Finding End Times, & Calculating Direction of Initial Fixation REMEMBER: For Events that DO NOT have fixations, write: “Exclude [Segment #, Event #], NO Fixations” in the processing tracking document.
A. Rename and Enter Percent of Data Tracked 1. Click on Event 2 and scroll to the right until you see the XDAT number. 2. Right click on the event and choose “Edit Event Name”. The new name should be the XDAT number (e.g. "146"). 3. In Excel, find the Tab associated with that XDAT number. There are two XDAT numbers for each tab. odd xdats (e.g. 129) go in the blue “T1” box even xdats (e.g. 130) go in the orange “T2” box 4. Open the “Percent Data Tracked” file for this subject (EyeDataà Processed Data Excel Sheets). 5.
In Excel, enter the percent of data tracked from the Fixation Period (Event 1) and the Picture Period (Event 2). Do NOT enter the percent sign. Minimize the Percent Tracked file.
B. Find the Times that the Last Samples were taken
1. In ASL Results, click on Event 1. In the middle of the project window, you will see rows representing the data samples collected 2. Scroll down to the last row. The time in the “Time_secs” column is the time that the last sample was taken (the time at which the fixation period ended). This should be approximately 2 seconds.
3. Record this time on your subject’s Excel Sheet in “End time of fixation Period”. Note: For the very first segment for each subject, the end time of Event 1 may be less than 2 seconds. That is okay. 4. In ASL Results, click on Event 2. 5. Scroll down to the last row. The time in the “Time_secs” column is the time that the last sample was taken (the time at which the cue period ended). This should be approximately 2 seconds. 6. Record this time on your subject’s Excel Sheet in “End time of Cue Picture Period”.
C. Calculate Direction of Initial Fixation 1. Click on Event 1àFixationsàFixation Sequence.
If any of the AOINames are “Central Region”, place a “1” in “Fixation on Cross at ALL during cross Period” in the Excel box
Look at the last fixation in the list (in red box above). If the AOIName = “Central Region” and the “Stop Time” = “End time of Fixation Period”, place a “1” in “Fixation on Fixation Cross Directly Before Pic Onset”
2. Click on Event 2à FixationsàFixation Sequence. • Find the first Fixation with an AOIName that contains “Cue” or “Neutral.” (see below)
Record the “Direction of Initial Fixation” in Excel. Cue Region (1); Neutral Region (2). Enter the Start Time and Duration of this fixation into Excel.
IMPORTANT: Mark Missing Data with “-‐9999”. For example, if the participant did not look at either of the pictures during this period, then mark this as -‐9999.
D. Repeat for remaining 39 trials. • •
Remember that Odd events (e.g. Event 3) are fixation cross periods and Even Events (e.g. Event 4) are picture periods. Also remember that each trial consists of two sequential events. For example Events 3 and 4 are part of the same trial.
Published on Sep 19, 2015