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The null hypothesis is that the means of\nthe distributions underlying the samples and control are equal.\n\nFirst, we test that the means of the distributions underlying the samples\nand control are unequal (``alternative='two-sided'``, the default).\n\n" }, { "__type": "Code", "__tag": 4050, "value": "import numpy as np\nfrom scipy.stats import dunnett\nsamples = [[3.8, 2.7, 4.0, 2.4], [2.8, 3.4, 3.7, 2.2, 2.0]]\ncontrol = [2.9, 3.0, 2.5, 2.6, 3.2]\nres = dunnett(*samples, control=control)\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "res.statistic\nres.pvalue\n", "execution_status": "failure" }, { "__type": "Text", "__tag": 4046, "value": "\nNow, we test that the means of the distributions underlying the samples are\ngreater than the mean of the distribution underlying the control.\n\n" }, { "__type": "Code", "__tag": 4050, "value": "res = dunnett(*samples, control=control, alternative='greater')\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "res.statistic\nres.pvalue\n", "execution_status": "failure" }, { "__type": "Text", "__tag": 4046, "value": "\nFor a more detailed example, see :ref:`hypothesis_dunnett`." } ], "title": [], "level": 0, "target": null }, "see_also": [ { "__type": "SeeAlsoItem", "__tag": 4028, "name": { "__type": "CrossRef", "__tag": 4002, "value": "hypothesis_dunnett", "reference": { "__type": "RefInfo", "__tag": 4000, "module": "current-module", "version": "current-version", "kind": "to-resolve", "path": "hypothesis_dunnett" }, "kind": "module" }, "descriptions": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "Extended example" } ] } ], "type": "ref" }, { "__type": "SeeAlsoItem", "__tag": 4028, "name": { "__type": "CrossRef", "__tag": 4002, "value": "tukey_hsd", "reference": { "__type": "LocalRef", "__tag": 4022, "kind": "module", "path": "scipy.stats._hypotests:tukey_hsd" }, "kind": "module" }, "descriptions": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "performs pairwise comparison of means." } ] } ], "type": "func" } ], "signature": { "__type": "SignatureNode", "__tag": 4029, "kind": "function", "parameters": [ { "__type": "SigParam", "__tag": 4030, "name": "samples", "annotation": "npt.ArrayLike", "kind": "VAR_POSITIONAL", "default": { "__type": "Empty", "__tag": 4031 } }, { "__type": "SigParam", "__tag": 4030, "name": "control", "annotation": "npt.ArrayLike", "kind": "KEYWORD_ONLY", "default": { "__type": "Empty", "__tag": 4031 } }, { "__type": "SigParam", "__tag": 4030, "name": "alternative", "annotation": "Literal['two-sided', 'less', 'greater']", "kind": "KEYWORD_ONLY", "default": "two-sided" }, { "__type": "SigParam", "__tag": 4030, "name": "rng", "annotation": "int | numpy.integer | numpy.random._generator.Generator | numpy.random.mtrand.RandomState | None", "kind": "KEYWORD_ONLY", "default": "None" }, { "__type": "SigParam", "__tag": 4030, "name": "random_state", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "KEYWORD_ONLY", "default": "None" } ], "return_annotation": "", "target_name": "dunnett" }, "references": [ ".. [1] Dunnett, Charles W. (1955) \"A Multiple Comparison Procedure for", " Comparing Several Treatments with a Control.\" Journal of the American", " Statistical Association, 50:272, 1096-1121,", " :doi:`10.1080/01621459.1955.10501294`", ".. [2] Thomson, M. L., & Short, M. D. (1969). Mucociliary function in", " health, chronic obstructive airway disease, and asbestosis. Journal", " of applied physiology, 26(5), 535-539.", " :doi:`10.1152/jappl.1969.26.5.535`" ], "qa": "scipy.stats._multicomp:dunnett", "arbitrary": [], "local_refs": [ "...", "alternative", "control", "res", "rng", "sample1", "sample2" ] }