{"id":"W1973554185","doi":"10.1016/s0024-3795(02)00342-7","title":"Regression models with unknown singular covariance matrix","year":2002,"lang":"en","type":"article","venue":"Linear Algebra and its Applications","topic":"Advanced Statistical Methods and Models","field":"Mathematics","cited_by":27,"is_retracted":false,"has_abstract":false,"ca_institutions":"University of Toronto","funders":"","keywords":"Mathematics; Invertible matrix; Estimation of covariance matrices; Scatter matrix; Covariance matrix; Covariance; Applied mathematics; Law of total covariance; Rational quadratic covariance function; Matrix (chemical analysis); Statistics; Estimator; Covariance function; Covariance intersection; Pure mathematics","routes":{"ca_aff":true,"ca_fund":false,"ca_venue":false,"about_ca":false,"invisible_to_affiliation_only":false},"retraction":null,"screen":null,"direct_labels":[],"prediction":{"model_version":"metacan-v3-hybrid-931329e0061c","candidate_categories":[],"consensus_categories":[],"category_scores_codex":[0.004391444,0.001541491,0.002723234,0.001537411,0.0006869871,0.002268832,0.00286966,0.00269137,0.00260207],"category_scores_gemma":[0.02317754,0.001391501,0.00177796,0.002944754,0.002623071,0.003826524,0.002250454,0.003365472,0.001667684],"about_ca_system_candidate":false,"about_ca_system_consensus":false,"about_ca_system_score_codex":0.0009785299,"about_ca_system_score_gemma":0.001769575,"about_ca_topic_candidate":false,"about_ca_topic_consensus":false,"about_ca_topic_score_codex":0.003219147,"about_ca_topic_score_gemma":0.002979449,"domain_scores_codex":[0.9957697,0.002011337,0.000192809,0.0008655081,0.0009428134,0.0002178945],"domain_scores_gemma":[0.988306,0.007535949,0.001404356,0.001626394,0.0009431096,0.0001842075],"domain_codex":null,"domain_gemma":null,"domain_candidate":null,"domain_consensus":null,"study_design_codex":"theoretical_or_conceptual","study_design_gemma":"theoretical_or_conceptual","study_design_scores_codex":[0.00007194712,0.00008703667,0.0009977287,0.0002227739,0.0002239635,0.0001788749,0.0001633562,0.3492443,0.00133859,0.5938518,0.00385907,0.04976053],"study_design_scores_gemma":[0.000008498571,0.00001438231,0.0001986576,0.00001594326,0.00003149071,0.00006161701,0.00001247459,0.7015966,0.0003554199,0.2963652,0.00131943,0.00002023108],"study_design_candidate":"theoretical_or_conceptual","study_design_consensus":"theoretical_or_conceptual","genre_codex":"methods","genre_gemma":"methods","genre_scores_codex":[0.005264984,0.0005204264,0.9924966,0.0003299496,0.00006699485,0.00001126182,0.0001212371,0.0002949815,0.000893556],"genre_scores_gemma":[0.5737419,0.004671463,0.3891693,0.0006820708,0.001331189,0.000366031,0.002100359,0.0006221244,0.0273155],"genre_candidate":"methods","genre_consensus":"methods","teacher_disagreement_score":0.004391444,"threshold_uncertainty_score":0.02322447,"prediction_status":"machine_predicted_unvalidated"},"machine_scores":{"provisional":true,"baseline":true,"maturity_gate_passed":false,"score_opus":0.08713431289302584,"score_gpt":0.3792479639747177,"score_spread":0.2921136510816918,"validation_status":"score_only:v0-immature-baseline","note":"Baseline scores from an immature model (maturity gate not passed). Scores rank; they never assert a category."}}