Data Viewer

Extracting Eyetracking Data with Data Viewer (Sample Report)

Resources: https://www.sr-research.com/data-viewer/

Data Viewer allows you to visualize, group, process and report EyeLink data easily. You need an Eyelink software license to be able to use Data Viewer.

Importing Experiment Builder data:

1. Create a new session: Open Data Viewer and save a new session. When you open and save a new data Viewer window, it will create a session (or project) where you will be able to save your data, your customized areas of interest, extraction templates and extracted results.

2. Import data: to import Eyelink files, called .edf, go to File >> Import Data >> Multiple Eyelink Data Files. You will have the option of importing only one participant file or more than one file. If you open the parent folder of your experiment, you will be able to select multiple .edf files from your results subfolder. Importing multiple .edf files can take a while. You will know that you have correctly exported and loaded them when they appear on the inspector window.

Extract data for specific Trial periods:

1. Full trial period: With this option, you can extract looking data for the full length of your trial. To do that, go to the top window, where it says “Full Trial Period” and select this option.

1. Specific trial periods: Alternatively you can select a specific time in your trial to be exported. To do that, on the top window, where it says “Full Trial Period”, select Edit… instead. This will open an Interest Period Manager window, click OK.

• On the Interest Period Editor, name your interest period. For example, you could name it "target-word-period" if you are extracting the time between word onset and 1800msec after.

• Use the EDF messages that you set on Experiment Builder to define your interest period. On IP Start Event Settings. Select EDF Message and type the "Message Text" that you used in Experiment Builder (note that the text should match exactly what you wrote on your experiment). For example, "DISPLAY_IMAGE_PAIR". This will be set as the start of your interest period. Repeat for the end of your interest period. On IP End Event Settings, select EDF message and type your "Message Text". For example "DISPLAY_FINAL_SCREEN". When you have defined your interest period, click OK. Your customized interest period will appear in the Interest Period Manager window. Note that in this window you can also customize the Sart/End Event Offset. For example, if you set the Start Event Offset to 2000 msec, this will set the start of your interest period window to 2000 msec after your "DISPLAY_IMAGE_PAIR" EDF message.

Select the Report type and Variables to be extracted:

Data Viewer allows you to extract looking data using multiple report types (for example, collapsing looks across fixations or interest areas).

• Sample Report: To process looking data using EyetrackingR you need the most detailed report, which exports the data based on Timestamps at the millisecond level. This is called Sample Report. To export this type of report, go to Analysis >> Reports >> Sample Report

• Variable Selection: Once you specify what report you want your data to be extracted with, you need to select the variables that will be in your output file. You can do that by moving the variable names from “Available Variables” to “Selected Variables” using the double arrows from the center of the display window. Some variables are standard Data Viewer variables, and others are part of your Data Source on Experiment Builder, for example: trial_type, target_word, experiment_order, block, etc. You can select both types of variables.

• Standard Data Viewer variables: These are the variables that you need in order to process the data with EyetrackingR and use the template script to clean your eyertacking data from KBH Lab.

RECORDING_SESSION_LABEL

TRIAL_INDEX

DATA_FILE

IP_START_TIME

TIMESTAMP

TRIAL_LABEL

LEFT_INTEREST_AREA_LABEL

RIGHT_INTEREST_AREA_LABEL

EYE_TRACKED

• Export the report: To extract the data, from the Sample Report with your selected variables, press “Next”, give a name to your output file and save it as a Text file .txt (note that these files can be huge and this process might take a while). For extremely large files (when you have a lot of participants or when you want to extract a large portion of your trial), you can consider lowering the sampling rate to 150Hz (currently it's set at 500Hz). This file will be inputed to the KBH data cleaning script template.