Two catalysts are being analyzed to determine how they affect the mean yield of a chemical process. Specifically, catalyst 1 is currently used; but catalyst 2 is acceptable. Because catalyst 2 is cheaper, it should be adopted, if it does not change the process yield. A test is run in the pilot plant and results in the data shown in Table 10.1. Figure 10.2 presents a normal probability plot and a comparative box plot of the data from the two samples. Is there any difference in the mean yields? Use ( alpha=0.05 ), and assume equal variances. egin{tabular}{ccc} hline TABLE 10.1 & Catalyst Yield Data, Example 10.5 \ hline Observation Number & Catalyst 1 & Catalyst 2 \ hline 1 & 91.50 & 89.19 \ hline 2 & 94.18 & 90.95 \ hline 3 & 92.18 & 90.46 \ hline 4 & 95.39 & 93.21 \ hline 5 & 91.79 & 97.19 \ hline 6 & 89.07 & 97.04 \ hline 7 & 94.72 & 91.07 \ hline 8 & 89.21 & 92.75 \ hline & ( ar{x}_{1}=92.255 ) & ( ar{x}_{2}=92.733 ) \ hline & ( s_{1}=2.39 ) & ( s_{2}=2.98 ) \ hline end{tabular}
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The first step is to state the null hypothesis and an alternative hypothesis. Null hypothesis: There is no difference in the mean yields of the two catalysts. (µ1 = µ2) Alternative hypothesis: There is a difference in the mean yields of the two catalysts. (µ1 ≠Show more…
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