{'fraction_non_alphanumeric': 0.02118003025718608, 'fraction_numerical': 0.0, 'mean_word_length': 5.186915887850467, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
On the robustness of the deflation-based FastICA estimator

This paper provides a rigorous statistical robustness analysis of the deflation-based FastICA estimator by deriving a compact closedform expression for its influence function (IF). The IF reveals the vulnerability of the FastICA estimator to outliers regardless of the used non-linearity. A cautionary finding is that even a moderate outlier towards certain directions can render the estimator deficient, i.e. having a separation performance worse than a plain guess. Based on the IF, a novel compact closed-form expression of the asymptotic covariance matrix of the FastICA estimator is also derived.