PipeLens: Identifying Interventions for Resolving Malfunctioning Data Science Pipelines

Data is a critical component of modern decision-making systems; system malfunctions (e.g., performance degradation and module failure) can often be traced back to a mismatch between the properties of the data and the assumptions of the system modules that process the data. For example, with the increasing use of open-source libraries to develop data science pipelines, common causes of system malfunctions include inappropriately configured data processing libraries for data cleaning tasks such as entity resolution or missing value imputation. Our objective is to resolve malfunctioning pipelines and improve their utility; we introduce PipeLens, a framework that leverages successful and unsuccessful runs of past pipelines for fixing pipeline malfunctions. PipeLens uses an acyclic graph representation of the pipeline and performs causal reasoning through interventions: when a system malfunctions with a given dataset, PipeLens modifies the pipeline (by changing its structure or the parameters of its modules) and observes the impact of this intervention on system behavior. To focus on useful interventions, we learn a proxy function that approximates the pipeline's utility over a dataset and guides the search for the best intervention. Unlike traditional observational analysis that reports correlations between system parameters and their behavior, we provide causally verified root causes and suggest pipeline modifications that rectify malfunctions. Empirical evaluation on four data science tasks over four real-world datasets demonstrates that PipeLens consistently outperforms baselines in terms of interventions performed to repair malfunctions while maintaining practical running times.