Concept explainers
A research specialist for a large seafood company plans to investigate bacterial growth on oysters and mussels subjected to three different storage temperatures. Nine cold-storage units are available. She plans to use three storage units for each of the three temperatures. One package of oysters and one package of mussels will be stored in each of the storage units for 2 weeks. At the end of the storage period, the packages will be removed and the bacterial count made for two samples from each package. The treatment factors of interest are temperature (levels: 0, 5, 10°C) and seafood (levels: oysters, mussels). She will also record the bacterial count for each package prior to placing seafood in the cooler. Identify each of the following components of the experimental design.
- a. Factors
- b. Factor levels
- c. Blocks
- d. Experimental unit
- e. Measurement unit
- f. Replications
- g. Treatments
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Chapter 2 Solutions
An Introduction to Statistical Methods and Data Analysis
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- Surfer Dude Swimsuit Company plans to produce a new line of quick-dry swimsuits. Five textile companies are competing for the company’s quick-dry fabric contract. To check the fabrics of the five companies, Surfer Dude selected 10 random swatches of fabric from each company, soaked them with water, and then measured the amount of time (in seconds) each swatch took to dry when exposed to sun and a temperature of 80 F. The following table contains the amount of time (in seconds) each of these swatches took to dry. CompanyA 756B 791C 773D 760E 763Time in seconds 801 750 696 761 794 773 723 699 699 753777 772 760 741 740 780 756 834 744 793768 812 810 770 801 794 791 742 799 803770 743 824 823 815 845 719 776 743 739 801 724 812 796 807 a) Write the null and alternative hypotheses. b) What are the degrees of freedom for the numerator and thedenominator? c) What are the values for the SSB, SSW, and SST. d) Show the rejection…arrow_forwardSurfer Dude Swimsuit Company plans to produce a new line of quick-dry swimsuits. Five textile companies are competing for the company’s quick-dry fabric contract. To check the fabrics of the five companies, Surfer Dude selected 10 random swatches of fabric from each company, soaked them with water, and then measured the amount of time (in seconds) each swatch took to dry when exposed to sun and a temperature of 80 F. The following table contains the amount of time (in seconds) each of these swatches took to dry.arrow_forwardPlease show the work clearly for the 2 sub parts! thank you!arrow_forward
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