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Shyh-Kang JengShyh-Kang JengDepartment of Electrical Engineering/Department of Electrical Engineering/

Graduate Institute of Communication/Graduate Institute of Communication/

Graduate Institute of Networking and Graduate Institute of Networking and MultimediaMultimedia

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Paired ComparisonsPaired ComparisonsMeasurements are recorded under Measurements are recorded under different sets of conditions different sets of conditions See if the responses differ See if the responses differ significantly over these setssignificantly over these setsTwo or more treatments can be Two or more treatments can be administered to the same or similar administered to the same or similar experimental unitsexperimental unitsCompare responses to assess the Compare responses to assess the effects of the treatmentseffects of the treatments

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Test Test HH00: : 11--22=0 =0

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Example 6.10: Nursing Home DataExample 6.10: Nursing Home Data

Nursing homes can be classified by Nursing homes can be classified by the owners: private (271), non-profit the owners: private (271), non-profit (138), government (107)(138), government (107)Costs: nursing labor, dietary labor, Costs: nursing labor, dietary labor, plant operation and maintenance plant operation and maintenance labor, housekeeping and laundry labor, housekeeping and laundry laborlaborTo investigate the effects of To investigate the effects of ownership on costsownership on costs

42424242

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Example 6.10: Nursing Home DataExample 6.10: Nursing Home Data

Nursing homes can be classified by Nursing homes can be classified by the owners: private (271), non-profit the owners: private (271), non-profit (138), government (107)(138), government (107)Costs: nursing labor, dietary labor, Costs: nursing labor, dietary labor, plant operation and maintenance plant operation and maintenance labor, housekeeping and laundry labor, housekeeping and laundry laborlaborTo investigate the effects of To investigate the effects of ownership on costsownership on costs

62626262

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63636363

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Strategy for Multivariate Strategy for Multivariate Comparison of TreatmentsComparison of Treatments

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103103103103

Importance of Experimental DesignImportance of Experimental DesignDifferences could appear in only one Differences could appear in only one of the many characteristics or a few of the many characteristics or a few treatment combinationstreatment combinationsDifferences may become lost among Differences may become lost among all the inactive onesall the inactive onesBest preventative is a good Best preventative is a good experimental designexperimental design– Do not include too many other variables Do not include too many other variables

that are not expected to show that are not expected to show differencesdifferences