Question

The accompanying table shows results from a study in which some dental patients were treated with amalgam restorations and others were treated with composite restorations that do not contain mercury. Use a 0.01 significance level to test for independence between the type of restoration and the presence of any adverse health conditions. Do amalgam restorations appear to affect health conditions? Click the icon to view the data on dental restorations. Determine the null and alternative hypotheses. A. Ho: The presence of any adverse health conditions is Hy: The presence of any adverse health conditions is Dental Restorations OB. Ho: Amalgam restorations adversely affect health con Hy: Amalgam restorations do not affect health conditid O C. Ho: The presence of any adverse health conditions is Hy: The presence of any adverse health conditions is Amalgam 135 Composite 153 Adverse Health Condition Reported No Adverse Health Condition Reported 133 115 O D. Ho: Amalgam restorations do not affect health conditio H : Amalgam restorations adversely affect health cong Print Done Determine the test statistic. x2 = (Round to three decimal places as needed.)

Answer 1

Amalgam 135 144.00 -9.00 Composite 153 144.00 9.00 Advertise Health Condition Reported 0 56 Observed Expected |O-E (0-E/E Observed Expected O-E (0-E /E 0.56 133 124.00 9.00 0.65 124.00 -9.00 Reported 0.65 x= O-E;) = 0.5625+0.5625+0.6532 +0.6532 = 2.431 The value of the test statistic is x2 = 2.431. Critical value = 6.635. Conclusion:

Since x? (=2.431) <6.635, then do not reject the null hypothesis. The percentage of any adverse health condition is not independent of type of restoration.