2.3 The FCD Dataset
To the purpose of the study, an appropriate FCD
dataset was queried in order to extract meaningful
information on mobility changes.
Such dataset, acquired from a third-party provider
and constituted by FCD collected by private and
commercial vehicles equipped with an onboard GPS
device, comprises of two tables. The most significant
table is a collection of GPS records, each
corresponding to a specific probe vehicle’s position.
Each record contains a trip identifier, and all the
records with the same trip identifier are part of the
same trip. A trip is defined as a collection of GPS
records between two points where the vehicle
remained stationary for at least 5 minutes. The other
table of the dataset is constituted by records each
containing the start and end GPS position of each
identified trip, with additional information on the
distance covered during the trip as provided by the
vehicle’s odometer.
Each record of the main table of the dataset also
includes additional data other than the GPS position
(latitude and longitude) and the trip identifier; among
these additional data is the vehicle identifier, the
corresponding timestamp, the vehicles’ direction (0-
360), the vehicle type (private/commercial), and other
data related to the vehicle’s position, including the
address and the municipality.
To focus on the Modena case study, the dataset
only comprises the trips which have at least one GPS
record within the Modena Municipality in November
2019 and November 2021.
2.4 Mobility Indicators
To perform the FCD analysis, different queries were
devised to allow for the extraction of meaningful
mobility indicators relevant to the context (e.g.,
number of distinct vehicles, average distance per
trip), both on the whole of the Modena Municipality,
as it constitutes the baseline against which schools’
areas were compared, and the schools’ areas
themselves, as such areas constitute the main subject
of the analysis. In particular, we focused on the
number of distinct probe vehicles identified in each
area, as this is an indicator which might reflect traffic
density.
For each of the areas considered, all the queries
were executed separately for each time frame of
interest—namely, 9-29 November 2019 and 8-28
November 2021—averaging the results per each day
of the week and per the five-day school week
(Monday through Saturday). Since the FCD dataset
allows for a separate analysis of private and
commercial vehicles, we specifically focused on
private vehicles, due to the fact that hardly any
commercial vehicle may be associated to students’
home-to-school trips.
After extracting the data for the selected time
frames in 2019 and 2021, relative deltas were
calculated to compare the difference between the
most meaningful indicators in each area. As a result,
the deltas relevant to the schools’ areas could also be
compared to the deltas relevant to the Modena
Municipality.
Finally, we estimated the FCD penetration rate
both in 2019 and 2021 to evaluate its impact on the
resulting key mobility indicators.
3 RESULTS
3.1 Modena Municipality
To the purpose of focalising on the changes directly
related to schools’ activities, mobility changes around
schools were compared to the changes in the whole of
the Modena Municipality, whose FCD were analysed
specifically to build a baseline for comparison. As
previously stated, the municipality’s FCD were
analysed focusing between 7 and 9 am, as such time
slot is the most relevant to schools-related mobility,
being 8:00 am the start time for lessons for all the 3
selected schools.
Table 2 reports the number of distinct private
probe vehicles detected within the municipality of
Modena between 7 and 9 am, averaged from Monday
to Saturday over the time frames 9-29 November
2019 and 8-28 November 2021, and the resulting
delta between 2019 and 2021.
Table 2: Average daily distinct private probe vehicles
(Monday to Saturday, 7-9 am) within Modena
Municipality.
Area
Daily
average
2019
Daily
average
2021
Delta
2021/2019
Modena
Municipality
685.8 632.9 -8%
Results show that, within the Modena
Municipality, the number of distinct private probe
vehicles detected in 2021 is 8% lower than in 2019.
In addition, we also calculated the variation of the
total distance covered by all the private probe
vehicles in the same time frame, and also the average