  Recent experimental studies have shed light on the intriguing possibility
that ion channels exhibit cooperative behaviour. However, a comprehensive
understanding of such cooperativity remains elusive, primarily due to
limitations in measuring separately the response of each channel. Rather, only
the superimposed channel response can be observed, challenging existing data
analysis methods. To address this gap, we propose IDC (Idealisation,
Discretisation, and Cooperativity inference), a robust statistical data
analysis methodology that requires only voltage-clamp current recordings of an
ensemble of ion channels. The framework of IDC enables us to integrate recent
advancements in idealisation techniques and coupled Markov models. Further, in
the cooperativity inference phase of IDC, we introduce a minimum distance
estimator and establish its statistical guarantee in the form of asymptotic
consistency. We demonstrate the effectiveness and robustness of IDC through
extensive simulation studies. As an application, we investigate gramicidin D
channels. Our findings reveal that these channels act independently, even at
varying applied voltages during voltage-clamp experiments. An implementation of
IDC is available from GitLab.
