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<br />excluded. <br />6) All cities were checl<ed to see if any mandatory watering restrictions or drought <br />warnings were in place during any of the years included in the analysis. It was <br />concluded that no such mandatory restrictions or warnings were in place. <br />7) A phone survey was conducted to address other factors or changes that could <br />affect water use, such as change in landscape size or irrigation system. However, <br />only a fraction of participants were able to be reached and were willing to tal<e the <br />survey. Therefore, the results could not be incorporated into the analysis. <br /> <br />Analysis Steps: After much discussion with the statisticians performing the analysis, it <br />was decided that it was acceptable to not have a control group for this study. The goal of <br />the analysis was to evaluate whether or not the program helped participants reduce their <br />water usage; since variables such as ET rates and watering restrictions were tal<en into <br />account, it was not necessary to evaluate non-participants. Another contributing factor <br />leading to this decision was the unrealistic possibility of being able to access and process <br />non-participants' water records. <br /> <br />Methods of Comparison: Initially, a comparison based upon the total number of gallons <br />used per property during the pre-inspection vs. post-inspection years was performed. <br />However, this comparison proved to be ineffective for several reasons. The change in <br />actual ET rates from year to year can vary by several inches. Therefore, if one year was <br />extremely dry, households would be much more lil<ely to use more water in that year as <br />compared with a year that was wetter than normal. Without tal<ing ET rates into account, <br />changes in water usage could be incorrectly attributed to STF instead of the simple <br />change in ET requirements. Additionally, the statisticians pointed out that without <br />referencing water usage in relation to landscape size, the change in gallons would not be <br />meaningful; instead a ratio or percent would need to be used. The last factor leading to <br />the decision not to use raw gallons in the comparison was due to the large variance in the <br />number of gallons used by each household. Households that were using extremely large <br />amounts of water would overshadow any changes made by households using less <br />amounts of water. <br /> <br />It was determined that percent above or below (noted as +/- ) ET would be the most <br />accurate and effective means of comparison. Percent +/- ET tal<es into account the ET <br />rate for the year being analyzed as well as the amount of watering used in relation to the <br />household's landscape size. Moreover, since all of the data was expressed as a ratio, the <br />problem of large water users overshadowing the rest of the group was considerably <br />reduced. <br /> <br />Standard Deviation Calculations and Normality Tests: The study groups (referred to as <br />2004AG and 2005AG) were analyzed in several different configurations for the purposes <br />of performing statistical tests. Each inspection group was analyzed as a whole for the <br />pre-inspection year and for the post-inspection year. Each group was also broken up into <br />two sub-groups: <br />Households watering> ET in the pre-inspection year <br />Households watering < ET in the pre-inspection year <br /> <br />24 <br />