Several experimental scenarios are outlined below; indicate the response variabl
ID: 3294532 • Letter: S
Question
Several experimental scenarios are outlined below; indicate the response variable, the treatment factors, blocking factors (if any), and type of design that should be used.
a. A semiconductor manufacturer has developed three methods for reducing particle count on wafers. All three methods are tested using fifteen different wafers and the after treatment particle count is obtained. The fifteen wafers are randomly divided into three groups of five and a given method is used for each group.
b. Three different washing solutions are being studied to assess their effectiveness in retarding bacteria growth in 5-gallon milk container using the concentration of bacteria in a post treatment wash. The analysis is done in a laboratory and only three trials can be run on any day. The experiment will be conducted over a four-day period. Note the experimenter conducting this study believes that days represent a source of variability that could impact the conclusions.
c. In a pulp industry experiment, the tensile strength of end product is supposed to be dependent upon percentage of hardwood concentration in raw pulp, the vat pressure and the cooking time of the pulp. The engineer performs an experiment with three different concentrations of hardwood, three levels of the pressure range and the cooking time for two time intervals, with three readings per treatment combination. There is no restriction on the order of the experiments.
d. A study was undertaken to evaluate the effect of five different ingredients on the reaction time of a chemical process. Each batch of new material is only large enough to permit five runs to be made. Furthermore, each run requires approximately 90 minutes, so only five runs can be made in one day. The engineer conducting the
Explanation / Answer
a. A semiconductor manufacturer has developed three methods for reducing particle count on wafers. All three methods are tested using fifteen different wafers and the after treatment particle count is obtained. The fifteen wafers are randomly divided into three groups of five and a given method is used for each group.
the response variable - particle count
the treatment factors - methods for reducing particle count on wafers
blocking factors - wafers
type of design that should be used. - between-group design - As the wafers in each block are random with no source of variability.
b. Three different washing solutions are being studied to assess their effectiveness in retarding bacteria growth in 5-gallon milk container using the concentration of bacteria in a post treatment wash. The analysis is done in a laboratory and only three trials can be run on any day. The experiment will be conducted over a four-day period. Note the experimenter conducting this study believes that days represent a source of variability that could impact the conclusions.
the response variable - concentration of bacteria
the treatment factors - post treatment wash
blocking factors - days
type of design that should be used. - Randomized block design (Anova) - As the days in each block may have source of variability.
c. In a pulp industry experiment, the tensile strength of end product is supposed to be dependent upon percentage of hardwood concentration in raw pulp, the vat pressure and the cooking time of the pulp. The engineer performs an experiment with three different concentrations of hardwood, three levels of the pressure range and the cooking time for two time intervals, with three readings per treatment combination. There is no restriction on the order of the experiments.
the response variable - tensile strength
the treatment factors - concentrations of hardwood, pressure range, cooking time
blocking factors - None
type of design that should be used. - 2^3 factorial design - As the response variable depends on 3 treatment factors
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.