Each individual in a sample of nursing home patients was cross-classified both with respect to cognitive state (normal or mild impairment, moderate impairment, severe impairment) and with respect to drug status (psychotropic drug change, psychotropic user without a change, no psychotropic medication). The following Minitab output resulted from a request to perform a chisquared analysis.

("Psychotropic Drug Initiation or Increased Dosage and the Acute Risk of Falls," BMC Geriatrics, 2013: 13:19).
a. Verify the expected frequency and contribution to x2 in the normal-drug change cell of the two-way table.
b. Does there appear to be an association between cognitive state and drug status? State and test the appropriate hypotheses using a significance level of .01.

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Drug change No change No med Total 189 Normal 83 90.06 0.554 237 218.25 1.611 86 97.69 1.398 406 46 64.1 34.83 0.263 3.584 70 155.35 84.40 0.122 2.456 41 69.54 37.78 1.030 0.275 157 60 Moderate 151 458 Severe 78 205 Total 289 852 Chi-sq11.294, DF4, P-Value0.023