## 3 Data Collection and Exploratory Data Analysis
### The Data Description for the Consideration Model
Specifically, inclusion required the respondents to have reported using the metro at least once in the preceding three months. Therefore, this measure not only represents potential demand, i.e., consideration or choice set inclusion, but also has a direct influence on the realized demand, i.e., footfall, as the individuals meeting this criterion have demonstrably used the train system. Overall, only one-third of the respondents reported considering the train during this period, indicating a stronger preference for other transport modes. Next, the differences in consideration rates across the segments based on the number, type, and exclusive availability of a motorized vehicle were examined (Figure 2). For this, the respondents were categorized into three categories. Those without vehicles or driving knowledge formed the captive group. Individuals owning only one two-wheeler, but who do not have exclusive access (i.e., vehicle is shared among multiple household members), are referred to as semi-captive travelers. The rest of the respondents had a motorized vehicle available for their exclusive use and were referred to as choice riders. Even within this group, individuals who owned only one two-wheeler and had exclusive access are termed as the two-wheeler choice riders and are considered a different sub-category compared to car-owning choice riders. Figure 2 shows that the share of individuals considering trains varies substantially across these segments. The semi-captive group has the highest consideration share (45%), suggesting that the potential demand is highest in this segment and is an important segment for promoting train usage. Interestingly, captive users had a consideration rate for the train (33%), which is less than the semi-captive respondents, probably because buses and shared autos are more accessible and less expensive than metro trains in Chennai (mean access distance to bus stop vs. train station is 0.5 km vs. 2.8 km, respectively). Thus, for this segment, the competition between public transit modes (bus and train) needs to be minimized through appropriate integration policies. Among choice riders, those with only a two-wheeler have a 32% train consideration rate, whereas car owners have a slightly lower rate of 30%. For this group, the service quality perception of transit relative to personal vehicles needs to be enhanced to encourage a modal shift. To examine the low consideration rates, perceptions of transit service quality were analyzed (Figure 3). More than half of the respondents were dissatisfied with the connectivity to multiple destinations (58%) and the ease of access to train stations (52%). Additionally, most users reported poor service quality in terms of comfort (75%) and convenience, including long-standing durations (67%) and crowding (63%). The perceptions of walkability were mixed. While 58% of the respondents felt that roads near railway stations were in good condition for walking, and 52% found crossing them safe and easy, 63% identified poor footpath usability as a major barrier to train access. Based on these findings, these factors were considered as potential explanatory variables in the consideration model. Figure 2: Consideration propensity based on captivity status, vehicle type, and number of vehicles.