README.md

Participants

75 students of the University of Potsdam all of whom were native speakers of German with normal or corrected-to-normal vision participated in the experiment. Participants with soft lenses were excluded from participation as soft lenses often pose serious challenges for the calibration of the eye-tracker. They were either students of biology or of physics in either their first semester of the BSc program (undergraduate) or graduate students currently attending a MSc or PhD program (graduate). Participants were requested to not have consumed any alcohol the day of the experiment and to not be suffering from sleep deprivation. Participants received a minium compensation of 10 EUR and up to 20 EUR if they answered a specific number of comprehension questions correctly.

	Physics	Biology
undergraduate	12	16
Advanced	20	27

Demographic data

The field of studies (including area specialization if applicable), the current semester of studies, gender, age, handedness, whether the participant was wearing contact lenses or glasses, hours of sleep the night before the experiment, alcohol consumption within 24h hours before the experiment, whether or not the participant had grown up bilingually, and the state (Bundesland) where the German language was acquired were recorded. Some of that data is made available in the participant_data.tsv file. Please see the CODEBOOK.md for more information on the available information.

column	description	value	range/choices
reader_id	unique reader identifier	int	0-105
reader_discipline	reader's field of study	categorical	{pyhsics,biology}
reader_discipline_numeric	numeric value of reader domain	int	biology==0 physics==1
level_of_studies	reader's level of studies	categorical	{undergraduate, graduate}
level_of_studies_numeric	numerical value of level_of_studies	int	undergraduate==0 graduate==1
discipline_level_of_studies	reader's domain expertise	categorical	biology-undergraduate biology-graduate physics-undergraduate physics-graduate
discipline_level_of_studies_numeric	numerical value of level_of_studies	int	biology-undergraduate==0 biology-graduate==1 physics-undergraduate==2 physics-graduate==3
glasses	whether reader had glasses	categorical	{yes,no,nan}
age	reader's age	float	18-41, nan
handedness	reader's handedness	categorical	{right,left}
hours_sleep	reader's number of sleep night before	float	0-11
alcohol	whether reader consumed alcohol night before experiment	categorical	{yes, no, nan}
gender	reader's gender	categorical	male,female,nan
gender_numeric	numerical value of reader's gender	int	male==0 female==1

Validation of comprehension questions

In order to test the usefulness of the comprehension questions, we conducted some additional experiments. In an online survey, participants were presented with the text questions without having access to the text. They were asked to answer the questions to the best of their knowledge. Please find more details in the paper.

Files

file name	description
participants_data.tsv	Contains demographic data of the participants of the eye-tracking experiment.
participant_response_accuracy.tsv	Contains the accuracy of the participants' answers to the comprehension and background questions during the eye-tracking experiment.
answer_coding_online_survey.csv	Contains all answer options for all questions of the online survey including attention checks as well as whether the answer option is the correct answer
response_data_online_survey.csv	Contains the raw data of answers as well as demographic information of the participants of the online survey. Note that the file answer_coding_online_survey.csv is needed to understand the contents of this file.
response_accuracy_online_survey.csv	Contains the accuracy and the explicit demographic information of the participants of the online survey.
ParticipantBriefing.pdf	Contains the information that was provided to the participants before the eye-tracking experiment.