## Neighborhood Aggregation Calculations

The neighborhood aggregator is a tool that allows users to summarize detailed scenario-level land use information to a higher level of geography, such as a TAZ or Census geography. Summarizing scenario results to these higher level geographies is helpful for a number of reasons, including using the data with other models such as travel demand models, watershed models, or school district facilities planning models. In addition, the ET City/Regional Travel model requires that detailed land use information be summarized to the neighborhood level. The calculation steps and formulas are detailed below.

### Using the Neighborhood Aggregator Tool

To use the neighorhood aggregation tool, the user needs to have a scenario loaded and have a neighborhood boundary, such as a TAZ layer, in their ArcGIS table of contents. The neighborhood boundary feature must be in a geodatabase to avoid truncated field names which will cause incomplete operation.

After opening the neighborhood aggregation window, the user will need to select the neighborhood layer they wish to aggregate. In addition, the user needs to select which of the fields they would like to aggregate. The fields present in the window are the same fields that the user has defined for tracking using the Attribute Manager window. If there are no fields visible in the neighborhood Aggregator window, the user needs to enable them for tracking in the Attribute Manager window. See more information about the attribute manager here.

### Acre Summary Calculation Format

#### 6 Buckets are Summarized for Each Neighborhood

##### PRE_VAC_ACRE:

= SUM ( VAC_ACRE )

##### PRE_DEVD_ACRE:

= SUM ( DEVD_ACRE )

##### ABANDON_DEVD_ACRE:

= SUM ( DEVD_ACRE * ABANDON_RATE )

##### DEVD_VAC_ACRE:

= SUM ( VAC_ACRE ) WHERE (DEV_TYPE <>”” AND ABANDON_RATE = 0)

##### UNREDEVD_DEVD_ACRE:

= SUM ( ( DEVD_ACRE * ( 1 – REDEV_RATE ) ) – ( DEVD_ACRE * ABANDON_RATE ) )

##### REDEVD_DEVD_ACRE:

= SUM ( DEVD_ACRE * REDEV_RATE )

#### Final 2 Buckets Calculated After Others are Summarized

##### TOT_VAC_ACRE:

= SUM ( ( PRE_VAC_ACRE – DEVD_VAC_ACRE ) + ABANDON_DEVD_ACRE )

##### TOT_DEVD_ACRE:

= SUM ( PRE_DEVD_ACRE – ABANDON_DEVD_ACRE )

### Attribute Sum Calculation Format

##### EX_PRE_

= SUM( EX_... )

##### EX_POST_

= SUM ( EX_... * ( 1 - ( REDEV_RATE+ABANDON_RATE )))

##### NEW_

= SUM ( VAR )

##### TOT_

= SUM ( EX_POST + NEW )

### Weighted Average Calculation Format

##### EX_PRE_

Numerator

=IF(EX_AVG_HH_SIZE>0,(DEVD_ACRE*EX_AVG_HH_SIZE),0)

Denominator

=IF(EX_AVG_HH_SIZE>0,(DEVD_ACRE),0)

##### EX_POST_

Numerator

=IF(AND(DEV_TYPE="",EX_AVG_HH_SIZE>0),(DEVD_ACRE*EX_AVG_HH_SIZE),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE>0),DEVD_ACRE*EX_AVG_HH_SIZE*(1-(REDEV_RATE+ABANDON_RATE)),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE=0),DEVD_ACRE*EX_AVG_HH_SIZE*(1-(REDEV_RATE+ABANDON_RATE)),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)=0,AVG_HH_SIZE>0),DEVD_ACRE*EX_AVG_HH_SIZE,0)

Denominator

=IF(AND(DEV_TYPE="",EX_AVG_HH_SIZE>0),(DEVD_ACRE),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE>0),IF(EX_AVG_HH_SIZE>0,DEVD_ACRE*(1-(REDEV_RATE+ABANDON_RATE)),0),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE=0),IF(EX_AVG_HH_SIZE>0,DEVD_ACRE*(1-(REDEV_RATE+ABANDON_RATE)),0),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)=0,AVG_HH_SIZE>0),IF(EX_AVG_HH_SIZE>0,DEVD_ACRE,0),0)

##### NEW_

Numerator

=IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE>0),((DEVD_ACRE*AVG_HH_SIZE*(REDEV_RATE+ABANDON_RATE))+(VAC_ACRE*AVG_HH_SIZE)),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)=0,AVG_HH_SIZE>0),VAC_ACRE*AVG_HH_SIZE,0)

Denominator

=IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE>0),(DEVD_ACRE*(REDEV_RATE+ABANDON_RATE))+(VAC_ACRE),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)=0,AVG_HH_SIZE>0),VAC_ACRE,0)

##### TOT_

Numerator

=IF(AND(DEV_TYPE="",EX_AVG_HH_SIZE>0),(DEVD_ACRE*EX_AVG_HH_SIZE),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE>0,EX_AVG_HH_SIZE>0),((DEVD_ACRE*AVG_HH_SIZE*REDEV_RATE)+(DEVD_ACRE*EX_AVG_HH_SIZE*(1-(REDEV_RATE+ABANDON_RATE)))+(VAC_ACRE*AVG_HH_SIZE)),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE>0,EX_AVG_HH_SIZE=0),((DEVD_ACRE*AVG_HH_SIZE*REDEV_RATE)+(VAC_ACRE*AVG_HH_SIZE)),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE=0),DEVD_ACRE*EX_AVG_HH_SIZE*(1-(REDEV_RATE+ABANDON_RATE)),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)=0,AVG_HH_SIZE>0),((DEVD_ACRE*EX_AVG_HH_SIZE)+(VAC_ACRE*AVG_HH_SIZE)),0)

Denominator

=IF(AND(DEV_TYPE="",EX_AVG_HH_SIZE>0),(DEVD_ACRE),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE>0,EX_AVG_HH_SIZE>0),(DEVD_ACRE*REDEV_RATE)+(DEVD_ACRE*(1-(REDEV_RATE+ABANDON_RATE)))+(VAC_ACRE),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE>0,EX_AVG_HH_SIZE=0),(DEVD_ACRE*REDEV_RATE)+(VAC_ACRE),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)<>0,AVG_HH_SIZE=0),DEVD_ACRE*(1-(REDEV_RATE+ABANDON_RATE)),0)

+IF(AND(DEV_TYPE>"",(REDEV_RATE+ABANDON_RATE)=0,AVG_HH_SIZE>0),(DEVD_ACRE+VAC_ACRE),0)

### Final step, for all except PRE:

= Sum( numerator bucket ) / Sum( denominator bucket )