balance_secondary_targets: Balances secondary targets to primary
In pbsag/ipfr: Develop Expansion Weights for a Survey

Description Usage Arguments Details Value

The average weight per record needed to satisfy targets is computed for both primary and secondary targets. Often, these can be very different, which leads to poor performance. The algorithm must use extremely large or small weights to match the competing goals. The secondary targets are scaled so that they are consistent with the primary targets on this measurement.

1 2	balance_secondary_targets(primary_targets, primary_seed, secondary_targets, secondary_seed, secondary_importance)

`primary_targets`	A `named list` of data frames. Each name in the list defines a marginal dimension and must match a column from the `primary_seed` table. The data frame associated with each named list element must contain a geography field (starts with "geo_"). Each row in the target table defines a new geography (these could be TAZs, tracts, clusters, etc.). The other column names define the marginal categories that targets are provided for. The vignette provides more detail.
`primary_seed`	In population synthesis or household survey expansion, this would be the household seed table (each record would represent a household). It could also be a trip table, where each row represents an origin-destination pair. Must contain a `pid` ("primary ID") field that is unique for each row. Must also contain a geography field that starts with "geo_".
`secondary_targets`	Same format as `primary_targets`, but they constrain the `secondary_seed` table.
`secondary_seed`	Most commonly, if the primary_seed describes households, the secondary seed table would describe a unique person with each row. Must also contain the `pid` column that links each person to their respective household in `primary_seed`. Must not contain any geography fields (starting with "geo_").
`secondary_importance`	A `real` between 0 and 1 signifying the importance of the secondary targets. At an importance of 1, the function will try to match the secondary tarets exactly. At 0, only the percentage distributions are used (see the vignette section "Target Agreement".)