A researcher conducted an observational study at a busy urban train station monitoring passengers' choices between two types of ticket barrier: one equipped with a modern biometric scan-to-enter system and another with a standard smartcard reader.

Using event sampling, recordings were made each time an individual passenger successfully passed through either of the two selected barriers during a continuous three-hour peak morning commute period from 7:30 am to 10:30 am. The data showing the frequency of barrier usage is presented in the table below.

Table 1: Frequency of ticket barrier use by passenger outfit type