{ "__type": "IngestedDoc", "__tag": 4010, "_content": { "Notes": { "__type": "Section", "__tag": 4015, "children": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "InlineRole", "__tag": 4003, "value": "pointbiserialr", "domain": null, "role": null, "inventory": null }, { "__type": "Text", "__tag": 4046, "value": " uses a t-test with " }, { "__type": "InlineCode", "__tag": 4051, "value": "n-1" }, { "__type": "Text", "__tag": 4046, "value": " degrees of freedom. 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Thus, an independent groups t Test with " }, { "__type": "InlineMath", "__tag": 4057, "value": "N-2" }, { "__type": "Text", "__tag": 4046, "value": " degrees of freedom may be used to test whether " }, { "__type": "InlineMath", "__tag": 4057, "value": "r_{pb}" }, { "__type": "Text", "__tag": 4046, "value": " is nonzero. 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[1] J. Lev, \"The Point Biserial Coefficient of Correlation\", Ann. Math.", " Statist., Vol. 20, no.1, pp. 125-126, 1949.", "", ".. [2] R.F. Tate, \"Correlation Between a Discrete and a Continuous", " Variable. Point-Biserial Correlation.\", Ann. Math. Statist., Vol. 25,", " np. 3, pp. 603-607, 1954.", "", ".. [3] D. Kornbrot \"Point Biserial Correlation\", In Wiley StatsRef:", " Statistics Reference Online (eds N. Balakrishnan, et al.), 2014.", " :doi:`10.1002/9781118445112.stat06227`" ], "qa": "scipy.stats._stats_py:pointbiserialr", "arbitrary": [], "local_refs": [ "axis", "keepdims", "nan_policy", "x", "y" ] }