Question

to study the effect of temperature on yield in a chemical process, five batches were produced at each of three temperature levels. The results follow. Temperature 50°C 60°C 70°C 33 30 25 23 31 30 35 34 30 38 23 32 31 27 33 a. Construct an analysis of variance table (to 2 decimals but p-value to 4 decimals, if necessary). Source of Variation Sum of Squares Degrees of Freedom Mean Square F p-value Treatments Error Total b. Use a level of significance to test whether the temperature level has an effect on the mean yield of the process. Calculate the value of the test statistic (to 2 decimals). The -value is What is your conclusion?

Answer 1

for the given data using Anova single factor in Excel we get output as ( Assuming alpha = 0.05)

Anova: Single Factor
SUMMARY
Groups	Count	Sum	Average	Variance
50	5	160	32	32
60	5	145	29	17.5
70	5	150	30	9.5
ANOVA
Source of Variation	SS	df	MS	F	P-value	F crit
Between Groups	23.3333333	2	11.66667	0.59322	0.567966	3.885294
Within Groups	236	12	19.66667
Total	259.333333	14