Future Work

The model explainability analysis indicated that there are some features with greater importance and whose interpretation is clearer than other features. Therefore, an ablation study could be performed to understand the contribution of the “weak” components to the overall model.

The developed models can predict whether a given passenger can make the connection successfully or not. That is, the task is framed as a classification problem. As future work, it would be interesting to directly predict the MCT. By improving the predictions of the time passengers need to transverse the airport, it would enable airlines to minimize the number of missed connections and to better serve their passengers. However, airlines and airports have little knowledge regarding passengers’ whereabouts in the airport and, within the collected data, there is no feature that can be used as target to learn the

predictions. Thus, the task can not be framed as a simple regression problem.

Given the airport’s structure graph and the routes that passengers have to make on the different connections, it is possible to formulate the problem as the task of estimating the distributions of the edge values. Figure 6.1 presents a simplified version of the SS connections.

Plat 10

Plat 14N

Plat 14S

Plat 20-22

...

Gate S 22-23

24-25

17-21 14-16 7-13

Plat 12

Bus Jet

Bridge

Terminal 1

Figure 6.1: Graph of the airport structure and diagram of the Schengen-Schengen connections proce-dures.

As can be seen in the Figure 6.1, the graph contains bidirectional edges, so it is an undirected graph.

Each edge represents a distance and the main objective of this problem is to obtain the time it takes to travel those distances. Although it seems like a problem with a trivial solution, it is very complex, since the time it takes for a passenger to travel a given distance is influenced by a large number of factors, such as the flow of passengers at the airport a a certain time, or if the passenger travels in a group, etc. A lot of these information is not available or it is unknown. Therefore, it can be assumed that each edge has a typical value (mean value) and a given standard deviation from that value of the time it takes to travel that edge. With this assumption, each edge can be modeled by a normal distribution and the objective of the problem is to find out which parameters best define these distributions taking into account all the samples in the dataset.

0 1

2

3 4 5

Figure 6.2: Simplified representation of the graph of the airport structure, schematized as an undirected graph in which each edge follows a given normal distribution.

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