Manufacturing and Product Development
An experiment was conducted to compare the acoustic properties of a control plastic (styrene) with four alternative treatment plastics. Independent random samples were selected, and the attenuation value of each piece was measured (in dB/mm at 5 MHz).
a. Conduct a one-way analysis of variance to test for an overall difference among the five population means. Use a 5 0.05.
b. Construct 95% Bonferroni confidence intervals only for the differences between each treatment plastic population mean and the control, styrene, population mean. Distribute the confidence level among the four comparisons (1 versus 2, 1 versus 3, 1 versus 4, and 1 versus 5) so that the simultaneous confidence level is 95%. Which treatment plastic attenuation means are significantly different from the control?