Settings parcel_sizes should not influence the profit

[hanase]

The feasibility model expects users to set parcel_sizes in the yaml file (default is 10000). A comment in the code claims that the value does not matter because it cancels out in the pro-forma computation. This is true for some of the pro-forma measures. However, this settings influences the construction time and hence the profit. Here is more detail.

Probably an easy fix would be to keep the construction time on the per-sqft scale and then multiply it by the real parcel size in _lookup_parking_cfg().

[jessicacamacho]

Hi @hanase ,

Thanks for pointing this out. We have changed _lookup_parking_cfg( ) in a branch called fixes_months_calculation, so that actual parcel sizes are taken into account when calculating construction months.

@hanase, @janowicz: please take a look at https://github.com/UDST/developer/compare/fixes_months_calculation, and let me know if you have any questions or suggestions before creating a PR.

Thanks!!

Jessica

[hanase]

Hi @jessicacamacho , thanks for looking into this!
It looks to me like the computation of month_values is not correct. The self.construction_months object is a matrix with columns corresponding to uses and rows corresponding to months (created here), so it's not form-specific.

[jessicacamacho]

Hi @hanase,

Thanks for your comment. I have made a modification that should solve it, weighting the construction_months values by use (from proforma.yaml) with the percentage of each use on each form:

developer/developer/sqftproforma.py

Lines 696 to 698 in 9f3d8eb

	month_keys = self.construction_sqft_for_months
	month_values = (self.forms[form] * self.construction_months).sum(axis=1)
	months_dict = dict(zip(month_keys, month_values))

Please let me know if you have any additional suggestions or questions.

Thanks!

Jessica

[hanase]

This works and gives the same results for different values of parcel_sizes. Thanks @jessicacamacho !
My suggestion would be to remove the need to have the parcel_sizes settings in the yaml file as it is quite confusing. Without reading the code one would not know that this setting has no impact on anything.