In February 2008, Speedo released its new LZR Racer swimsuit made of polyurethane and woven elastane nylon. With its patented technology, the compression of the LZR Racer holds the body in a more...

Extracted text: In February 2008, Speedo released its new LZR Racer swimsuit made of polyurethane and woven elastane nylon. With its patented technology, the compression of the LZR Racer holds the body in a more hydrodynamic position while reducing muscle oscillation and skin vibration for a more efficient performance when compared to the spandex LYCRA suits. The compression also reduces the entry of water between the suit and the body, which can be a source of drag. To further reduce drag, the fabric repels water, the zipper is on the inside, and the manufacturing process uses ultrasonic welding (rather than traditional sewing) to bond the fabrics and eliminate the seams. The LZR Racer was developed by Mactex in association with the Australian Institute of Sport and wind tunnel-tested at NASA. At the 2008 Beijing olympics, swimmers wearing the suit won 94% of the races, received 89% of the medals, and set 23 out of 25 world records. Suppose you are a student on your university's swim team and want to compare the new LZR Racer suit with the traditional spandex LYCRA suit. After recruiting nine other members of your team (and obtaining a grant to purchase ten LZR Racer suits and 10 LYCRA suits), you conduct an experiment. Each swimmer will swim 50 m freestyle while wearing the LYRCA suit and 50 m freestyle while wearing the LZR Racer suit. This is a repeated measures design. (a) What is the major advantage of this repeated measures design over an independent groups design that randomly assigns five swimmers to swim 50 m freestyle using the LYCRA suit with the other five swimmers swimming 50 m freestyle using the LZR Racer suit? O The swimmers are not accustomed to wearing the new suits. O There are 10 swimmers, and the pool only has eight lanes. O An independent groups design does not control for the different abilities of the swimmers in each group. O There are too many ways in which to randomly select five of the 10 swimmers to swim 50 m freestyle using the LYCRA suit. (b) Regarding the order in which each swimmer wears the LZR Racer suit and the LYCRA suit, which of the following statements is true? O For easy record keeping, all swimmers should wear the LZR Racer suit first. O The order in which the suits are worn should be randomly selected (counterbalancing) to reduce order effects in your experiment. O All swimmers may select which suit to wear first, so long as the data manager is told which suit is being worn. O For easy record keeping, all swimmers should wear the LYCRA suit first. (c) Which of the following are additional ways to control for other sources of variability in your experiment? O have all swimmers swim at approximately the same time of day O have all swimmers use the same warm-up routine O have all swimmers use the same stroke O all of the above (d) An experiment is called double blind if neither the subject nor the people collecting the data know which treatment the subject is receiving. Regarding blinding, which of the following is possible for your experiment? O It is possible for both the swimmers and the data collector to be blind in your experiment. O It is possible for the data collector to be blind, but not the swimmers. O It is not possible for either the swimmers or the data collector to be blind. O It is possible for the swimmers to be blind, but not the data collector.