national multiple family submetering and allocation billing program ...

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Difference in Annual Water Use
per Unit Compared to In-Rent (kgal)
30
20
10
0
-10
-20
-30
-10.05
-1.71
-40
Submetered
N=79
RUBS
N=136
Figure 5.15 Difference in adjusted average annual water use of impacted properties
compared to in-rent properties – Model #3
Table 5.19 Model #3 coefficients and significance of independent variables
Independent Variable B* Std. Error t P-value
(Constant) 27.37 5.15 5.315 .000
Property was built before 1995 11.40 2.55 4.470 .000
Property is a senior citizen/retirement
community
-8.37 3.30 -2.539 .011
Property has a play area 6.54 2.13 3.064 .002
Property has a cooling tower 9.85 4.11 2.397 .017
Property is billed through RUBS method -1.71 2.09 -0.817 .414
Property is submetered -10.05 2.79 -3.604 .000
Average commodity charge for
water/wastewater † -1.76 0.32 -5.489 .000
Average number of bedrooms per unit † 18.18 1.86 9.753 .000
Average rent per bedroom † -0.006 .004 -1.598 .111
Dependent Variable: Indoor water use per unit (average 2001, 2002)
* Represents the magnitude of each independent variable in kgal per year per dwelling unit
†
Continuous variables, change is seen for every dollar or bedroom added
Besides submetering, five other independent variables in the model were also statistically
significant. One that was not statistically significant was the average rent per bedroom at a
property. It was found to covary with location, which is accounted for in the model with average
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