Database of Subjective Driver Ratings for Brazilian Freeway Scenarios

Dataset Description

This dataset contains 10,387 subjective ratings of freeway driving experiences collected by means of a web survey completed (or partially completed) by 1,614 Brazilian drivers. Each participant watched up to 12 one-minute video clips, each depicting a freeway driving scenario from the driver viewpoint. A total of 418 video clips depicted 128 scenarios that were systematically varied across five key factors: number of lanes in the trip direction, speed limit, road grade, truck percentage, and traffic density, according to a fractional factorial design.

Each rating, on a scale of 0 to 100, represents the perceived quality of the driving experience, with higher scores indicating a more positive perception (from "poor" to "excellent" on a continuous scale). Each line in the dataset represents a rating and includes the following variables:

Variable
Definition

IDuser
A unique identifier for each participant.

IDvideo
A identifier for each video clip watched by the participant.

Rating
The subjective rating of the driving experience, on a scale of 0 (poor) to 100 (excellent).

TimeToRateVideo
The time taken by the participant to rate the video clip, measured in seconds, from the moment the video clip is presented on the screen to the moment the participant proceeds to the next video clip.

Video_clip_scenario
A string encoding the specific conditions of the freeway scenario depicted in each video clip watched by the participant.

Scenario Encoding

The Video_clip_scenario variable uses a specific encoding scheme to represent the different driving conditions (scenarios). Each factor is represented by up to 3 letters and a numeric value. For example,  NL3_G4_SL120_PT10_k132_veh1 indicates the first replication of scenario with 3 lanes, 4% uphill grade, a 120 km/h speed limit, 10% trucks, and a traffic density of 13.2 veh/km/lane. The factors and their numeric values are explained in the following table:

Factor
Definition
Number of levels
Numeric values

NL:
Number of lanes in the driving direction
2
3 or 4

G:
Grade (%)
2
1 (nearly level grade) or 4 (steep uphill grade)

SL:
Posted speed limit (km/h)
4
90, 100, 110 or 120

PT:
Percentage of trucks in the traffic stream (%)
4
0, 10, 20 or 30

k:
Traffic density (in 0.1 veh/km/ln)
16
36, 48, 72, ..., 168, 180 or 192

veh:
Scenario replication identifier 
N.A.
integer > 0

These ratings were obtained using a web survey, approved by the Brazilian Human Research Ethics Committee (CEP-EACH-USP, protocol number: 2034830). The ratings.csv file contains the unfiltered ratings obtained on that web survey.

For additional information about the dataset, contact the project leader or the data curator.  If you find this dataset useful for your research, please let the authors know. We appreciate your feedback and would be interested to hear how you use the data.