The following is the number of trips and the number of households by the number of persons per household and the level of household income in a given traffic zone. Persons/household. 1 2 3 5 or more Low No. of households 93 72 59 120 13 No. of trips 222 341 417 1010 107 Income Medium No. of households 149 138 125 109 37 No. of trips 616 853 1025 1186 457 High No. of households 96 27 33 40 33 The forecasted number of households in the study area for a target year is shown below. No. of trips 360 205 381 471 423 The forecasted number of households in the study area for a target year is shown below. Persons/household 1 2 3 5 or more Low 120 100 90 150 30 Income Medium 280 220 190 180 60 High 130 40 50 70 60 (a) Calculate the forecasted number of trips for each combination of the number of persons per household and the level of household income. (b) Alternatively, trip rate can be estimated using the following linear regression equation: Trip rate=0.46 + 1.96 NPERSON + 1.66 * HINCOME where NPERSON no. of persons per household (- 5 for 5 or more persons in household); HINCOME level of household income (-0 for low income. - 1 for medium income, -2 for high income) (a) Calculate the forecasted number of trips for each combination of the number of persons per household and the level of household income. (b) Alternatively, trip rate can be estimated using the following linear regression equation: Trip rate=0.46 + 1.96 NPERSON + 1.66* HINCOME where NPERSON = no. of persons per household (-5 for 5 or more persons in household); HINCOME level of household income (=0 for low income, 1 for medium income, = 2 for high income) Calculate the forecasted number of trips for each household type using this estimated trip rate. (e) Compare underlying assumptions and limitations of the methods used in (a) and (b).