Data Dictionary for WFF Microsimulation Model

This document provides a data dictionary for the Working for Families (WFF) microsimulation model, specifically detailing the inputs and outputs of the famsim function in src/wff_microsim.py.

famsim Function Parameters

These are the scalar parameters passed directly to the famsim function, which define the policy settings and other model constants.

Parameter Name	Type	Description
ftc1	float	FTC entitlement for the eldest child.
ftc2	float	FTC entitlement for subsequent children.
iwtc1	float	IWTC entitlement for 1-3 children.
iwtc2	float	IWTC entitlement for 4+ children.
bstc	float	BSTC entitlement.
mftc	float	MFTC guaranteed income amount before tax (i.e., gross income).
abatethresh1	float	First abatement threshold.
abatethresh2	float	Second abatement threshold (if any).
abaterate1	float	Abatement rate for the first abatement threshold.
abaterate2	float	Abatement rate for the second abatement threshold.
bstcthresh	float	Abatement threshold for BSTC.
bstcabate	float	Abatement rate for BSTC.
wagegwt	float	Wage growth - growth in average ordinary weekly earnings on a March year basis.
daysinperiod	int	Number of days in the period.

famsim Input DataFrame Columns

These are the columns expected in the input pandas DataFrame (df) passed to the famsim function.

Column Name	Type	Description
familyinc	float	Total family income.
maxkiddays	int	The maximum number of days a child is part of the family.
maxkiddaysbstc	int	The maximum number of days a child is eligible for BSTC.
FTCwgt	float	Weight for FTC calculation.
IWTCwgt	float	Weight for IWTC calculation.
iwtc_elig	int	Flag indicating IWTC eligibility (1 if eligible, 0 otherwise).
BSTC0wgt	float	Weight for BSTC for children under 1.
BSTC01wgt	float	Weight for BSTC for children between 1 and 3.
BSTC1wgt	float	Weight for BSTC for children over 3.
pplcnt	int	Number of people in the family.
MFTC_total	float	Total MFTC amount.
MFTC_elig	int	Flag indicating MFTC eligibility (1 if eligible, 0 otherwise).
sharedcare	int	Flag indicating if care is shared (1 if shared, 0 otherwise).
sharecareFTCwgt	float	Weight for shared care FTC.
sharecareBSTC0wgt	float	Weight for shared care BSTC for children under 1.
sharecareBSTC01wgt	float	Weight for shared care BSTC for children between 1 and 3.
sharecareBSTC1wgt	float	Weight for shared care BSTC for children over 3.
MFTCwgt	float	Weight for MFTC.
iwtc	float	IWTC amount.
selfempind	int	Flag indicating self-employment (1 if self-employed, 0 otherwise).

famsim Output DataFrame Columns

These are the new columns added to the input DataFrame by the famsim function, containing the calculated WFF entitlements and intermediate values.

Column Name	Type	Description
familyinc_grossed_up	float	Family income adjusted for wage growth.
abate_amt	float	The amount of abatement based on family income.
BSTCabate_amt	float	The amount of abatement for Best Start Tax Credit.
maxFTCent	float	Maximum Family Tax Credit entitlement.
maxIWTCent	float	Maximum In-Work Tax Credit entitlement.
maxBSTC0ent	float	Maximum Best Start Tax Credit entitlement for children under 1.
maxBSTC01ent	float	Maximum Best Start Tax Credit entitlement for children between 1 and 3.
maxBSTC1ent	float	Maximum Best Start Tax Credit entitlement for children over 3.
maxMFTCent	float	Maximum Minimum Family Tax Credit entitlement.
FTCcalc	float	Calculated Family Tax Credit entitlement.
IWTCcalc	float	Calculated In-Work Tax Credit entitlement.
MFTCcalc	float	Calculated Minimum Family Tax Credit entitlement.
BSTCcalc	float	Calculated Best Start Tax Credit entitlement.
FTCcalcTEMP	float	Temporary calculation for FTC, used internally.
carryforward_abate	float	Amount of abatement carried forward from FTC to IWTC calculation.