Q2 Figures and Tables

Impact of visible flood factor scores on sale price

Separated Timing and Underlying Risk

This file now loads saved model objects, tables, and marginal effects from scripts rather than estimating the models while rendering the Quarto document. The heavy computations are created by the scripts in the scripts/ folder and saved under outputs/q2_marginaleffects/.

event == TRUE for all sales that occurred after First Street released its flood risk data. high_ff_score == TRUE for properties with a Flood Factor score of 5 or higher.

Basic TWFE Models

Using Effective Map Status

	County	Triad Interactions
eventTRUE	0.058***	0.011
	(0.006)	(0.007)
change_typeAlways SFHA × eventTRUE	0.041	-0.423***
	(0.042)	(0.045)
change_typeChanges SFHA × eventTRUE	0.181***	0.030
	(0.038)	(0.038)
high_ff_scoreTRUE × eventTRUE	-0.103***	-0.117***
	(0.012)	(0.014)
change_typeAlways SFHA × high_ff_scoreTRUE × eventTRUE	-0.065	0.185***
	(0.060)	(0.051)
change_typeChanges SFHA × high_ff_scoreTRUE × eventTRUE	-0.014	-0.109
	(0.095)	(0.095)
eventTRUE × TriadNorth		-0.020**
		(0.007)
eventTRUE × TriadSouth		0.190***
		(0.007)
change_typeAlways SFHA × eventTRUE × TriadNorth		0.537***
		(0.054)
change_typeAlways SFHA × eventTRUE × TriadSouth		0.424***
		(0.058)
high_ff_scoreTRUE × eventTRUE × TriadNorth		0.125***
		(0.020)
high_ff_scoreTRUE × eventTRUE × TriadSouth		0.110***
		(0.019)
change_typeAlways SFHA × high_ff_scoreTRUE × eventTRUE × TriadNorth		-0.232***
		(0.064)
change_typeAlways SFHA × high_ff_scoreTRUE × eventTRUE × TriadSouth		-0.158*
		(0.069)
Num.Obs.	666566	666566
R2	0.859	0.861
R2 Within	0.002	0.013
RMSE	0.32	0.32
Std.Errors	by: pin10	by: pin10
FE: pin	X	X
FE: sale_year	X	X

Using Preliminary Map Status

	County	Triad Interactions
eventTRUE	0.190	0.189
	(0.133)	(101.675)
prelim_sfha_categoryAlways SFHA × eventTRUE	-0.091	-0.601
	(0.139)	(101.674)
prelim_sfha_categoryNever SFHA × eventTRUE	-0.132	-0.178
	(0.133)	(101.676)
prelim_sfha_categoryRemoved from prelim SFHA × eventTRUE	-0.020	-0.206
	(0.144)	(101.675)
high_ff_scoreTRUE × eventTRUE	0.230+	-0.658*
	(0.133)	(0.286)
prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE × eventTRUE	-0.399**	0.726*
	(0.146)	(0.290)
prelim_sfha_categoryNever SFHA × high_ff_scoreTRUE × eventTRUE	-0.333*	0.541+
	(0.134)	(0.286)
prelim_sfha_categoryRemoved from prelim SFHA × high_ff_scoreTRUE × eventTRUE	-0.190	0.032
	(0.197)	(0.280)
eventTRUE × TriadNorth		-0.005
		(101.674)
eventTRUE × TriadSouth		0.191***
		(0.007)
prelim_sfha_categoryAlways SFHA × eventTRUE × TriadNorth		0.522
		(101.674)
prelim_sfha_categoryNever SFHA × eventTRUE × TriadNorth		-0.015
		(101.676)
prelim_sfha_categoryRemoved from prelim SFHA × eventTRUE × TriadNorth		0.020
		(101.675)
prelim_sfha_categoryAlways SFHA × eventTRUE × TriadSouth		0.424***
		(0.058)
high_ff_scoreTRUE × eventTRUE × TriadNorth		0.883***
		(0.253)
high_ff_scoreTRUE × eventTRUE × TriadSouth		0.109***
		(0.019)
prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE × eventTRUE × TriadNorth		-0.994***
		(0.260)
prelim_sfha_categoryNever SFHA × high_ff_scoreTRUE × eventTRUE × TriadNorth		-0.759**
		(0.253)
prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE × eventTRUE × TriadSouth		-0.157*
		(0.068)
Num.Obs.	666566	666566
R2	0.859	0.861
R2 Within	0.002	0.013
RMSE	0.32	0.32
Std.Errors	by: pin10	by: pin10
FE: pin	X	X
FE: sale_year	X	X

Combined Indicator & Preliminary SFHA Status

	County	Triad Interactions
highff_postTRUE	-0.099***	-0.153***
	(0.011)	(0.013)
highff_postTRUE × change_type_prelimAlways SFHA	-0.026	-0.239***
	(0.044)	(0.025)
highff_postTRUE × change_type_prelimChanges SFHA	0.270*	-0.539***
	(0.123)	(0.014)
highff_postTRUE × TriadNorth		0.105***
		(0.019)
highff_postTRUE × TriadSouth		0.301***
		(0.018)
highff_postTRUE × change_type_prelimAlways SFHA × TriadNorth		0.301***
		(0.035)
highff_postTRUE × change_type_prelimChanges SFHA × TriadNorth		0.807***
		(0.116)
highff_postTRUE × change_type_prelimAlways SFHA × TriadSouth		0.267***
		(0.036)
Num.Obs.	666687	666687
R2	0.859	0.860
R2 Within	0.002	0.005
RMSE	0.32	0.32
Std.Errors	by: pin10	by: pin10
FE: pin	X	X
FE: sale_year	X	X

ETWFE Comparisons

These models use the etwfe package. The saved outputs below are produced by scripts/q2_dissertation_02_etwfe_models.R.

Base Model

This version does not include SFHA status or Triad in the equation.

ETWFE: Base Model
Effect	Estimate	Std. Error
High Flood Factor × Post Release	-0.103***	(0.011)
+ p < 0.1, * p < 0.05, ** p < 0.01, *** p < 0.001

Regional Heterogeneity

ETWFE: Regional Heterogeneity
Effect	Estimate	Std. Error
High Flood Factor × Post Release: City	-0.101***	(0.015)
High Flood Factor × Post Release: North	-0.056***	(0.013)
High Flood Factor × Post Release: South	0.133***	(0.012)
+ p < 0.1, * p < 0.05, ** p < 0.01, *** p < 0.001

Question 2

Table 15: Question 2 Main Model

	Effective, no Triad	Effective × Triad	Preliminary × Triad
eventTRUE	0.058***	0.011	0.011
	(0.006)	(0.007)	(0.007)
change_typeAlways SFHA × eventTRUE	0.041	-0.423***
	(0.042)	(0.045)
change_typeChanges SFHA × eventTRUE	0.181***	0.030
	(0.038)	(0.038)
high_ff_scoreTRUE × eventTRUE	-0.103***	-0.117***	-0.117***
	(0.012)	(0.014)	(0.014)
change_typeAlways SFHA × high_ff_scoreTRUE × eventTRUE	-0.065	0.185***
	(0.060)	(0.051)
change_typeChanges SFHA × high_ff_scoreTRUE × eventTRUE	-0.014	-0.109
	(0.095)	(0.095)
eventTRUE × TriadNorth		-0.020**	-0.020**
		(0.007)	(0.007)
eventTRUE × TriadSouth		0.190***	0.191***
		(0.007)	(0.007)
change_typeAlways SFHA × eventTRUE × TriadNorth		0.537***
		(0.054)
change_typeAlways SFHA × eventTRUE × TriadSouth		0.424***
		(0.058)
high_ff_scoreTRUE × eventTRUE × TriadNorth		0.125***	0.125***
		(0.020)	(0.020)
high_ff_scoreTRUE × eventTRUE × TriadSouth		0.110***	0.109***
		(0.019)	(0.019)
change_typeAlways SFHA × high_ff_scoreTRUE × eventTRUE × TriadNorth		-0.232***
		(0.064)
change_typeAlways SFHA × high_ff_scoreTRUE × eventTRUE × TriadSouth		-0.158*
		(0.069)
change_type_prelimAlways SFHA × eventTRUE			-0.423***
			(0.045)
change_type_prelimChanges SFHA × eventTRUE			-0.029
			(0.054)
change_type_prelimAlways SFHA × high_ff_scoreTRUE × eventTRUE			0.185***
			(0.051)
change_type_prelimChanges SFHA × high_ff_scoreTRUE × eventTRUE			-0.509***
			(0.056)
change_type_prelimAlways SFHA × eventTRUE × TriadNorth			0.537***
			(0.054)
change_type_prelimChanges SFHA × eventTRUE × TriadNorth			0.162
			(0.131)
change_type_prelimAlways SFHA × eventTRUE × TriadSouth			0.424***
			(0.058)
change_type_prelimAlways SFHA × high_ff_scoreTRUE × eventTRUE × TriadNorth			-0.235***
			(0.064)
change_type_prelimChanges SFHA × high_ff_scoreTRUE × eventTRUE × TriadNorth			0.644***
			(0.174)
change_type_prelimAlways SFHA × high_ff_scoreTRUE × eventTRUE × TriadSouth			-0.157*
			(0.068)
Num.Obs.	666566	666566	666566
R2	0.859	0.861	0.861
R2 Within	0.002	0.013	0.013
RMSE	0.32	0.32	0.32
Std.Errors	by: pin10	by: pin10	by: pin10
FE: pin	X	X	X
FE: sale_year	X	X	X

Main Marginal Effects

Change Type: Sequential Comparisons

term	contrast	estimate	std.error	conf.low	conf.high	p.value
change_type	Always SFHA - Never SFHA	-0.06	0.01	-0.08	-0.05	0.00
change_type	Changes SFHA - Always SFHA	-0.63	6824.69	-13376.77	13375.51	1.00

Post Release by Effective SFHA Change Type

term	contrast	change_type	estimate	std.error	conf.low	conf.high	p.value
event	TRUE - FALSE	Never SFHA	0.04	0.00	0.03	0.05	0.00
event	TRUE - FALSE	Always SFHA	0.00	0.01	-0.02	0.03	0.72
event	TRUE - FALSE	Changes SFHA	0.22	0.04	0.15	0.29	0.00

Never SFHA: Post-Release Effect

This is the targeted contrast from the effective-map model for properties categorized as Never SFHA, allowing high and low Flood Factor properties to be represented in the comparison.

term	contrast	change_type	Triad	high_ff_score	event	estimate	std.error	conf.low	conf.high	p.value
event	TRUE - FALSE	Never SFHA	City	FALSE	FALSE	0.01	0.01	-0.00	0.03	0.12
event	TRUE - FALSE	Never SFHA	City	TRUE	FALSE	-0.11	0.01	-0.13	-0.08	0.00

Never Preliminary SFHA: Post-Release Effect by Triad

term	contrast	Triad	estimate	std.error	conf.low	conf.high	p.value
event	TRUE - FALSE	City	-0.05	0.01	-0.06	-0.03	0.00

All Effective Map Status Options

term	contrast	change_type	high_ff_score	event	estimate	std.error	conf.low	conf.high	p.value
change_type	Always SFHA - Never SFHA	Never SFHA	FALSE	FALSE	0.00	NA	NA	NA	NA
change_type	Always SFHA - Never SFHA	Always SFHA	FALSE	FALSE	0.00	NA	NA	NA	NA
change_type	Always SFHA - Never SFHA	Changes SFHA	FALSE	FALSE	0.00	NA	NA	NA	NA
change_type	Always SFHA - Never SFHA	Never SFHA	TRUE	FALSE	0.00	NA	NA	NA	NA
change_type	Always SFHA - Never SFHA	Always SFHA	TRUE	FALSE	0.00	NA	NA	NA	NA
change_type	Always SFHA - Never SFHA	Changes SFHA	TRUE	FALSE	0.00	NA	NA	NA	NA
change_type	Always SFHA - Never SFHA	Never SFHA	FALSE	TRUE	0.04	0.04	-0.04	0.12	0.33
change_type	Always SFHA - Never SFHA	Always SFHA	FALSE	TRUE	0.04	0.04	-0.04	0.12	0.33
change_type	Always SFHA - Never SFHA	Changes SFHA	FALSE	TRUE	0.04	0.04	-0.04	0.12	0.33
change_type	Always SFHA - Never SFHA	Never SFHA	TRUE	TRUE	-0.02	0.04	-0.11	0.06	0.58
change_type	Always SFHA - Never SFHA	Always SFHA	TRUE	TRUE	-0.02	0.04	-0.11	0.06	0.58
change_type	Always SFHA - Never SFHA	Changes SFHA	TRUE	TRUE	-0.02	0.04	-0.11	0.06	0.58
change_type	Changes SFHA - Never SFHA	Never SFHA	FALSE	FALSE	-0.52	8385.62	-16436.03	16434.98	1.00
change_type	Changes SFHA - Never SFHA	Always SFHA	FALSE	FALSE	-0.52	8385.62	-16436.03	16434.98	1.00
change_type	Changes SFHA - Never SFHA	Changes SFHA	FALSE	FALSE	-0.52	8385.62	-16436.03	16434.98	1.00
change_type	Changes SFHA - Never SFHA	Never SFHA	TRUE	FALSE	-0.52	8385.61	-16436.03	16434.98	1.00
change_type	Changes SFHA - Never SFHA	Always SFHA	TRUE	FALSE	-0.52	8385.61	-16436.03	16434.98	1.00
change_type	Changes SFHA - Never SFHA	Changes SFHA	TRUE	FALSE	-0.52	8385.61	-16436.03	16434.98	1.00
change_type	Changes SFHA - Never SFHA	Never SFHA	FALSE	TRUE	-0.34	8385.62	-16435.85	16435.17	1.00
change_type	Changes SFHA - Never SFHA	Always SFHA	FALSE	TRUE	-0.34	8385.62	-16435.85	16435.17	1.00
change_type	Changes SFHA - Never SFHA	Changes SFHA	FALSE	TRUE	-0.34	8385.62	-16435.85	16435.17	1.00
change_type	Changes SFHA - Never SFHA	Never SFHA	TRUE	TRUE	-0.36	8385.62	-16435.87	16435.16	1.00
change_type	Changes SFHA - Never SFHA	Always SFHA	TRUE	TRUE	-0.36	8385.62	-16435.87	16435.16	1.00
change_type	Changes SFHA - Never SFHA	Changes SFHA	TRUE	TRUE	-0.36	8385.62	-16435.87	16435.16	1.00
event	TRUE - FALSE	Never SFHA	FALSE	FALSE	0.06	0.01	0.05	0.07	0.00
event	TRUE - FALSE	Always SFHA	FALSE	FALSE	0.10	0.04	0.02	0.18	0.02
event	TRUE - FALSE	Changes SFHA	FALSE	FALSE	0.24	0.04	0.16	0.32	0.00
event	TRUE - FALSE	Never SFHA	TRUE	FALSE	-0.04	0.02	-0.08	-0.01	0.02
event	TRUE - FALSE	Always SFHA	TRUE	FALSE	-0.07	0.05	-0.16	0.02	0.14
event	TRUE - FALSE	Changes SFHA	TRUE	FALSE	0.12	0.09	-0.05	0.29	0.16
event	TRUE - FALSE	Never SFHA	FALSE	TRUE	0.06	0.01	0.05	0.07	0.00
event	TRUE - FALSE	Always SFHA	FALSE	TRUE	0.10	0.04	0.02	0.18	0.02
event	TRUE - FALSE	Changes SFHA	FALSE	TRUE	0.24	0.04	0.16	0.32	0.00
event	TRUE - FALSE	Never SFHA	TRUE	TRUE	-0.04	0.02	-0.08	-0.01	0.02
event	TRUE - FALSE	Always SFHA	TRUE	TRUE	-0.07	0.05	-0.16	0.02	0.14
event	TRUE - FALSE	Changes SFHA	TRUE	TRUE	0.12	0.09	-0.05	0.29	0.16
high_ff_score	TRUE - FALSE	Never SFHA	FALSE	FALSE	0.18	22938.20	-44957.86	44958.22	1.00
high_ff_score	TRUE - FALSE	Always SFHA	FALSE	FALSE	0.18	22938.20	-44957.86	44958.22	1.00
high_ff_score	TRUE - FALSE	Changes SFHA	FALSE	FALSE	0.18	22938.20	-44957.87	44958.22	1.00
high_ff_score	TRUE - FALSE	Never SFHA	TRUE	FALSE	0.18	22938.20	-44957.86	44958.22	1.00
high_ff_score	TRUE - FALSE	Always SFHA	TRUE	FALSE	0.18	22938.20	-44957.86	44958.22	1.00
high_ff_score	TRUE - FALSE	Changes SFHA	TRUE	FALSE	0.18	22938.20	-44957.87	44958.22	1.00
high_ff_score	TRUE - FALSE	Never SFHA	FALSE	TRUE	0.07	22938.21	-44958.00	44958.15	1.00
high_ff_score	TRUE - FALSE	Always SFHA	FALSE	TRUE	0.01	22938.22	-44958.07	44958.08	1.00
high_ff_score	TRUE - FALSE	Changes SFHA	FALSE	TRUE	0.06	22938.21	-44958.01	44958.13	1.00
high_ff_score	TRUE - FALSE	Never SFHA	TRUE	TRUE	0.07	22938.21	-44958.00	44958.15	1.00
high_ff_score	TRUE - FALSE	Always SFHA	TRUE	TRUE	0.01	22938.22	-44958.07	44958.08	1.00
high_ff_score	TRUE - FALSE	Changes SFHA	TRUE	TRUE	0.06	22938.21	-44958.01	44958.13	1.00

High Flood Factor Effects by SFHA Change Type and Triad

term	contrast	change_type	Triad	high_ff_score	event	estimate	std.error	conf.low	conf.high	p.value
event	TRUE - FALSE	Never SFHA	City	TRUE	FALSE	-0.11	0.01	-0.13	-0.08	0.00
event	TRUE - FALSE	Never SFHA	North	TRUE	FALSE	-0.00	0.02	-0.03	0.03	0.92
event	TRUE - FALSE	Never SFHA	South	TRUE	FALSE	0.19	0.01	0.16	0.22	0.00
event	TRUE - FALSE	Always SFHA	City	TRUE	FALSE	-0.34	0.03	-0.40	-0.29	0.00
event	TRUE - FALSE	Always SFHA	North	TRUE	FALSE	0.06	0.02	0.03	0.10	0.00
event	TRUE - FALSE	Always SFHA	South	TRUE	FALSE	0.22	0.02	0.18	0.27	0.00
event	TRUE - FALSE	Changes SFHA	City	TRUE	FALSE	-0.18	0.09	-0.36	-0.01	0.04
event	TRUE - FALSE	Changes SFHA	North	TRUE	FALSE	-0.08	0.09	-0.26	0.09	0.36
event	TRUE - FALSE	Changes SFHA	South	TRUE	FALSE	0.12	0.09	-0.06	0.28	0.18

Is the High Flood Factor Effect Moderated by SFHA Status?

These outputs estimate whether the estimated effect of high Flood Factor exposure differs across FEMA SFHA status categories.

HighFF Post Model Table

	Change Type × HighFF Post	Change Type × HighFF Post × Triad	Partially interacted
highff_postTRUE	-0.099***	-0.153***
	(0.011)	(0.013)
change_typeAlways SFHA × highff_postTRUE	-0.025	-0.239***
	(0.044)	(0.025)
change_typeAlways SFHA × highff_postTRUE × TriadNorth		0.304***
		(0.035)
change_typeAlways SFHA × highff_postTRUE × TriadSouth		0.267***
		(0.036)
change_typeAlways SFHA × highff_postFALSE			0.258***
			(0.029)
Num.Obs.	666687	666687	666687
R2	0.859	0.860	0.859
R2 Within	0.002	0.005	0.005
RMSE	0.32	0.32	0.32
Std.Errors	by: pin10	by: pin10	by: pin10
FE: pin	X	X	X
FE: sale_year	X	X	X

HighFF Post by Change Type

term	contrast	change_type	estimate	std.error	conf.low	conf.high	p.value
highff_post	TRUE - FALSE	Never SFHA	-0.10	0.01	-0.12	-0.08	0.00
highff_post	TRUE - FALSE	Always SFHA	-0.12	0.04	-0.21	-0.04	0.00
highff_post	TRUE - FALSE	Changes SFHA	0.07	0.09	-0.10	0.23	0.44

Hypothesis Test: HighFF Post by Change Type

estimate	std.error	conf.low	conf.high	p.value
0.03	0.04	-0.06	0.11	0.57

HighFF Post × Triad by Change Type

term	contrast	change_type	estimate	std.error	conf.low	conf.high	p.value
highff_post	TRUE - FALSE	Never SFHA	-0.06	0.01	-0.07	-0.04	0.00
highff_post	TRUE - FALSE	Always SFHA	-0.04	0.01	-0.07	-0.02	0.00
highff_post	TRUE - FALSE	Changes SFHA	0.07	0.09	-0.10	0.23	0.44

Hypothesis Test: HighFF Post × Triad by Change Type

estimate	std.error	conf.low	conf.high	p.value
-0.01	0.01	-0.04	0.02	0.39

Partially Interacted HighFF Post Model

term	contrast	change_type	estimate	std.error	conf.low	conf.high	p.value
highff_post	TRUE - FALSE	Never SFHA	-0.05	0.01	-0.07	-0.03	0.00
highff_post	TRUE - FALSE	Always SFHA	-0.09	0.03	-0.14	-0.04	0.00
highff_post	TRUE - FALSE	Changes SFHA	0.07	0.09	-0.10	0.23	0.44

HighFF Post Grid by Change Type and Triad

term	contrast	change_type	Triad	highff_post	estimate	std.error	conf.low	conf.high	p.value
highff_post	TRUE - FALSE	Never SFHA	City	FALSE	-0.15	0.01	-0.18	-0.13	0.00
highff_post	TRUE - FALSE	Never SFHA	North	FALSE	-0.05	0.01	-0.08	-0.02	0.00
highff_post	TRUE - FALSE	Never SFHA	South	FALSE	0.15	0.01	0.12	0.17	0.00
highff_post	TRUE - FALSE	Always SFHA	City	FALSE	-0.39	0.02	-0.44	-0.35	0.00
highff_post	TRUE - FALSE	Always SFHA	North	FALSE	0.02	0.02	-0.02	0.06	0.39
highff_post	TRUE - FALSE	Always SFHA	South	FALSE	0.17	0.02	0.13	0.22	0.00
highff_post	TRUE - FALSE	Changes SFHA	City	FALSE	-0.23	0.09	-0.41	-0.06	0.01
highff_post	TRUE - FALSE	Changes SFHA	North	FALSE	-0.13	0.09	-0.30	0.04	0.14
highff_post	TRUE - FALSE	Changes SFHA	South	FALSE	0.07	0.09	-0.10	0.23	0.44

Q2 Robustness Checks

Preliminary SFHA × High FF × Post by Triad

Q2 robustness: preliminary SFHA status, high Flood Factor, and post-release period by Triad

	South	North	City
prelim_sfha_categoryAlways SFHA	0.121
	(9661.662)
eventTRUE	-0.041	0.214+	-0.352***
	(7667.747)	(0.126)	(0.046)
prelim_sfha_categoryAlways SFHA × eventTRUE	0.115	-0.076
	(7667.748)	(0.130)
prelim_sfha_categoryNever SFHA × eventTRUE	0.112	-0.190	0.416***
	(7667.747)	(0.126)	(0.045)
prelim_sfha_categoryRemoved from prelim SFHA × eventTRUE	0.058	-0.214
	(7667.746)	(0.253)
high_ff_scoreTRUE × eventTRUE	-0.106	0.274*	0.064
	(12036.355)	(0.126)	(0.050)
prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE × eventTRUE	0.124	-0.317*
	(12036.356)	(0.131)
prelim_sfha_categoryNever SFHA × high_ff_scoreTRUE × eventTRUE	0.098	-0.268*	-0.181***
	(12036.355)	(0.127)	(0.052)
prelim_sfha_categoryRemoved from prelim SFHA × high_ff_scoreTRUE × eventTRUE	-0.401	0.015
	(12036.356)	(0.282)
prelim_sfha_categoryRemoved from prelim SFHA		-0.220
		(6614.763)
high_ff_scoreTRUE		-0.268
		(9536.533)
prelim_sfha_categoryNever SFHA × high_ff_scoreTRUE			-0.154
			(11216.345)
Num.Obs.	162244	150765	353557
R2	0.825	0.919	0.840
R2 Within	0.001	0.001	0.004
RMSE	0.33	0.21	0.35
Std.Errors	by: pin10	by: pin10	by: pin10
FE: pin	X	X	X
FE: sale_year	X	X	X

Preliminary SFHA × HighFF Post by Triad

Q2 robustness: preliminary SFHA status and HighFF × Post by Triad

	South	North	City
highff_postTRUE	-0.560***	0.462***	-0.347***
	(0.008)	(0.008)	(0.023)
prelim_sfha_categoryAlways SFHA × highff_postTRUE	0.588***	-0.392***
	(0.023)	(0.020)
prelim_sfha_categoryNever SFHA × highff_postTRUE	0.558***	-0.456***	0.237***
	(0.015)	(0.016)	(0.026)
prelim_sfha_categoryRemoved from prelim SFHA × highff_postTRUE		-0.197
		(0.126)
Num.Obs.	162249	150789	353649
R2	0.825	0.919	0.840
R2 Within	0.000	0.000	0.003
RMSE	0.33	0.21	0.35
Std.Errors	by: pin10	by: pin10	by: pin10
FE: pin	X	X	X
FE: sale_year	X	X	X

Diagnostics and Data Checks

Analysis Data

observations	parcels	pin10s	min_sale_year	max_sale_year	post_release_sales	high_ff_sales
668596.00	291321.00	189559.00	2010.00	2025.00	233933.00	96395.00

Preliminary Control Groups

group	observations
group_C_A	490915.00
group_C_B	162730.00
group_C_C	14188.00
group_C_D	595.00
group_T_A	13.00
group_T_B	155.00

Diagnostics: Dropped Terms

These tables show terms removed from the presentation tables because their standard errors were missing or larger than the threshold used in the scripts. In this fixed-effects setup, these terms are usually either not identified within PIN over time or are extremely sparse combinations.

Basic TWFE: Effective

term	estimate	std.error	p.value
change_typeChanges SFHA	-0.52	8385.62	1.00
high_ff_scoreTRUE	0.18	22938.21	1.00
change_typeChanges SFHA	-0.70	6824.69	1.00
high_ff_scoreTRUE	0.14	18241.24	1.00
high_ff_scoreTRUE:TriadSouth	-0.66	23358.89	1.00

Basic TWFE: Preliminary

term	estimate	std.error	p.value
prelim_sfha_categoryRemoved from prelim SFHA	0.63	4990.68	1.00
high_ff_scoreTRUE	-0.82	15138.30	1.00
prelim_sfha_categoryRemoved from prelim SFHA	0.64	5963.56	1.00
high_ff_scoreTRUE	-2.21	14596.62	1.00
high_ff_scoreTRUE:TriadSouth	0.47	26163.32	1.00

Basic TWFE: HighFF + Preliminary

term	estimate	std.error	p.value
change_type_prelimChanges SFHA	0.42	5458.37	1.00
change_type_prelimChanges SFHA	-1.13	16485.64	1.00
change_type_prelimChanges SFHA:TriadSouth	1.57	13553.70	1.00

Q2 Main Models

term	estimate	std.error	p.value
change_typeChanges SFHA	-0.52	8385.62	1.00
high_ff_scoreTRUE	0.18	22938.21	1.00
change_typeChanges SFHA	-0.70	6824.69	1.00
high_ff_scoreTRUE	0.14	18241.24	1.00
high_ff_scoreTRUE:TriadSouth	-0.66	23358.89	1.00

HighFF Post Models

term	estimate	std.error	p.value
change_typeChanges SFHA	-0.56	5003.58	1.00
change_typeChanges SFHA	-0.49	4986.58	1.00
change_typeNever SFHA:highff_postFALSE	0.48	5710.80	1.00
change_typeChanges SFHA:highff_postFALSE	-0.44	7243.08	1.00
change_typeNever SFHA:highff_postTRUE	0.32	5710.80	1.00
change_typeChanges SFHA:highff_postTRUE	-0.70	7243.08	1.00
highff_postFALSE:TriadNorth	-1.21	12558.94	1.00
highff_postTRUE:TriadNorth	-1.06	12558.95	1.00
highff_postFALSE:TriadSouth	-1.58	30815.59	1.00
highff_postTRUE:TriadSouth	-1.24	30815.60	1.00

Robustness: Preliminary + High FF

term	estimate	std.error	p.value
prelim_sfha_categoryAlways SFHA	0.12	9661.66	1.00
eventTRUE	-0.04	7667.75	1.00
prelim_sfha_categoryAlways SFHA:eventTRUE	0.12	7667.75	1.00
prelim_sfha_categoryNever SFHA:eventTRUE	0.11	7667.75	1.00
prelim_sfha_categoryRemoved from prelim SFHA:eventTRUE	0.06	7667.75	1.00
high_ff_scoreTRUE:eventTRUE	-0.11	12036.35	1.00
prelim_sfha_categoryAlways SFHA:high_ff_scoreTRUE:eventTRUE	0.12	12036.36	1.00
prelim_sfha_categoryNever SFHA:high_ff_scoreTRUE:eventTRUE	0.10	12036.35	1.00
prelim_sfha_categoryRemoved from prelim SFHA:high_ff_scoreTRUE:eventTRUE	-0.40	12036.36	1.00
prelim_sfha_categoryRemoved from prelim SFHA	-0.22	6614.76	1.00
high_ff_scoreTRUE	-0.27	9536.53	1.00
prelim_sfha_categoryNever SFHA:high_ff_scoreTRUE	-0.15	11216.34	1.00

Robustness: Preliminary + HighFF Post

term	estimate	std.error	p.value
prelim_sfha_categoryAlways SFHA	0.29	8010.39	1.00
prelim_sfha_categoryRemoved from prelim SFHA	-0.30	6658.25	1.00

Ordinal & Continuous FF Risk Variable

See q2_FF_variable_checks.qmd

Appendix B

Figures 13-14 in Q2_assumption_graphs.qmd

Figures 17-19, 22 in Q2 assumption graphs.qmd

Table 18: Q2 PreTrend Slope Test

Pre-event slope tests

	SFHA × time	HighFF × time	SFHA×HighFF × time
(Intercept)	-79.755***	-79.809***	-79.488***
	(1.379)	(1.480)	(1.481)
sale_year	0.046***	0.046***	0.045***
	(0.001)	(0.001)	(0.001)
in_eff_sfhaTRUE	8.126		-23.496
	(11.878)		(14.752)
sale_year × in_eff_sfhaTRUE	-0.004		0.011
	(0.006)		(0.007)
high_ff_scoreTRUE		0.057	-3.149
		(3.934)	(3.997)
sale_year × high_ff_scoreTRUE		0.000	0.002
		(0.002)	(0.002)
in_eff_sfhaTRUE × high_ff_scoreTRUE			54.719**
			(20.624)
sale_year × in_eff_sfhaTRUE × high_ff_scoreTRUE			-0.027**
			(0.010)
Num.Obs.	415163	415039	415039
R2	0.021	0.023	0.026
RMSE	0.88	0.88	0.87
Std.Errors	by: pin10	by: pin10	by: pin10
We want NOT statistically significant interaction slope terms for variables interacted with sale_year.

Has TWFE:

Pre-event slope tests

	SFHA × time	HighFF × time	SFHA×HighFF × time
prelim_sfha_categoryRemoved from prelim SFHA	-0.102		-0.399
	(14406.255)		(14379.640)
sale_year × prelim_sfha_categoryAdded to prelim SFHA	-0.008***		-0.009***
	(0.001)		(0.001)
sale_year × prelim_sfha_categoryAlways SFHA	-0.011***		-0.004
	(0.003)		(0.005)
sale_year × prelim_sfha_categoryRemoved from prelim SFHA	-0.037**		-0.043**
	(0.012)		(0.014)
sale_year × high_ff_scoreTRUE		-0.010***	-0.010***
		(0.001)	(0.001)
sale_year × prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE			-0.004
			(0.006)
sale_year × prelim_sfha_categoryRemoved from prelim SFHA × high_ff_scoreTRUE			0.068+
			(0.039)
Num.Obs.	324657	324536	324536
R2	0.855	0.855	0.855
R2 Within	0.000	0.001	0.001
RMSE	0.33	0.33	0.33
Std.Errors	by: pin10	by: pin10	by: pin10
FE: pin	X	X	X
FE: sale_year	X	X	X
We want NOT statistically significant interaction slope terms for variables interacted with sale_year.

Models (by Triad)

Pre-event slope tests by Triad

	North	City	South
(Intercept)	-78.917***	-84.827***	-81.719***
	(2.356)	(2.226)	(1.841)
sale_year	0.045***	0.048***	0.046***
	(0.001)	(0.001)	(0.001)
prelim_sfha_categoryAdded to prelim SFHA	59.347		-67.465***
	(275.889)		(1.841)
prelim_sfha_categoryAlways SFHA	-83.918***	146.034**	11.138
	(16.006)	(53.143)	(11.910)
prelim_sfha_categoryRemoved from prelim SFHA	-828.008***		39.442
	(2.356)		(35.527)
high_ff_scoreTRUE	-21.903*	5.049	-2.566
	(9.091)	(4.545)	(6.211)
sale_year × prelim_sfha_categoryAdded to prelim SFHA	-0.030		0.033***
	(0.137)		(0.001)
sale_year × prelim_sfha_categoryAlways SFHA	0.041***	-0.072**	-0.006
	(0.008)	(0.026)	(0.006)
sale_year × prelim_sfha_categoryRemoved from prelim SFHA	0.411***		-0.020
	(0.001)		(0.018)
sale_year × high_ff_scoreTRUE	0.011*	-0.002	0.001
	(0.004)	(0.002)	(0.003)
prelim_sfha_categoryAdded to prelim SFHA × high_ff_scoreTRUE	0.415
	(35.639)
prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE	111.004***	-149.973**	-27.589+
	(25.620)	(55.851)	(16.736)
prelim_sfha_categoryRemoved from prelim SFHA × high_ff_scoreTRUE	807.137***		-171.455*
	(46.397)		(70.946)
sale_year × prelim_sfha_categoryAdded to prelim SFHA × high_ff_scoreTRUE	-0.002
	(0.017)
sale_year × prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE	-0.055***	0.074**	0.014+
	(0.013)	(0.028)	(0.008)
sale_year × prelim_sfha_categoryRemoved from prelim SFHA × high_ff_scoreTRUE	-0.401***		0.085*
	(0.023)		(0.035)
Num.Obs.	99215	230396	104739
R2	0.045	0.032	0.034
RMSE	0.73	0.90	0.77
Std.Errors	by: pin10	by: pin10	by: pin10

Does not have TWFE:

Pre-event slope tests by Triad

	(1)
(Intercept)	-84.827***
	(2.226)
sale_year	0.048***
	(0.001)
prelim_sfha_categoryAdded to prelim SFHA	-67.465***
	(1.841)
prelim_sfha_categoryAlways SFHA	146.034**
	(53.145)
prelim_sfha_categoryRemoved from prelim SFHA	39.442
	(2697.185)
high_ff_scoreTRUE	5.049
	(4.545)
TriadNorth	5.911+
	(3.241)
TriadSouth	3.108
	(2.889)
sale_year × prelim_sfha_categoryAdded to prelim SFHA	0.033***
	(0.001)
sale_year × prelim_sfha_categoryAlways SFHA	-0.072**
	(0.026)
sale_year × prelim_sfha_categoryRemoved from prelim SFHA	0.068
	(5.412)
sale_year × high_ff_scoreTRUE	-0.002
	(0.002)
prelim_sfha_categoryAdded to prelim SFHA × high_ff_scoreTRUE	-0.692
	(0.520)
prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE	-149.973**
	(55.852)
prelim_sfha_categoryRemoved from prelim SFHA × high_ff_scoreTRUE	-171.455
	(8493.346)
sale_year × TriadNorth	-0.003+
	(0.002)
sale_year × TriadSouth	-0.002
	(0.001)
prelim_sfha_categoryAdded to prelim SFHA × TriadNorth	126.813
	(275.884)
prelim_sfha_categoryAlways SFHA × TriadNorth	-229.952***
	(55.502)
prelim_sfha_categoryRemoved from prelim SFHA × TriadNorth	-867.450
	(20231.662)
prelim_sfha_categoryAlways SFHA × TriadSouth	-134.896*
	(54.463)
high_ff_scoreTRUE × TriadNorth	-26.952**
	(10.164)
high_ff_scoreTRUE × TriadSouth	-7.615
	(7.696)
sale_year × prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE	0.074**
	(0.028)
sale_year × prelim_sfha_categoryRemoved from prelim SFHA × high_ff_scoreTRUE	0.085
	(4.219)
sale_year × prelim_sfha_categoryAdded to prelim SFHA × TriadNorth	-0.063
	(0.137)
sale_year × prelim_sfha_categoryAlways SFHA × TriadNorth	0.114***
	(0.027)
sale_year × prelim_sfha_categoryRemoved from prelim SFHA × TriadNorth	0.329
	(12.003)
sale_year × prelim_sfha_categoryAlways SFHA × TriadSouth	0.067*
	(0.027)
sale_year × prelim_sfha_categoryRemoved from prelim SFHA × TriadSouth	-0.109
	(6.394)
sale_year × high_ff_scoreTRUE × TriadNorth	0.013**
	(0.005)
sale_year × high_ff_scoreTRUE × TriadSouth	0.004
	(0.004)
prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE × TriadNorth	260.976***
	(61.447)
prelim_sfha_categoryRemoved from prelim SFHA × high_ff_scoreTRUE × TriadNorth	978.591
	(22663.419)
prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE × TriadSouth	122.383*
	(58.306)
sale_year × prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE × TriadNorth	-0.129***
	(0.030)
sale_year × prelim_sfha_categoryRemoved from prelim SFHA × high_ff_scoreTRUE × TriadNorth	-0.487
	(11.244)
sale_year × prelim_sfha_categoryAlways SFHA × high_ff_scoreTRUE × TriadSouth	-0.061*
	(0.029)
Num.Obs.	434350
R2	-0.449
RMSE	1.06
Std.Errors	by: pin10

Table 21: Q2 placebo test

Placebo test (cut at 2017)

	(1)	(2)	(3)	(4)
event_pbPostPB	0.174	0.195
	(5041.657)	(5021.943)
high_ff_scoreTRUE × event_pbPostPB	-0.065***	-0.060***
	(0.010)	(0.010)
change_typeAlways SFHA		-0.705		-2.495
		(9197.351)		(11848.211)
change_typeChanges SFHA		0.308
		(4813.836)
change_typeAlways SFHA × event_pbPostPB		-0.021
		(0.030)
change_typeChanges SFHA × event_pbPostPB		-0.011
		(0.131)
high_ff_scoreTRUE × change_typeAlways SFHA × event_pbPostPB		-0.034
		(0.044)
high_ff_scoreTRUE			-0.784	-0.231
			(8798.696)	(10589.770)
eventTRUE			0.023***	0.022***
			(0.006)	(0.006)
high_ff_scoreTRUE × eventTRUE			-0.106***	-0.103***
			(0.011)	(0.012)
change_typeAlways SFHA × eventTRUE				0.040
				(0.042)
change_typeChanges SFHA × eventTRUE				0.176***
				(0.037)
high_ff_scoreTRUE × change_typeAlways SFHA × eventTRUE				-0.063
				(0.060)
high_ff_scoreTRUE × change_typeChanges SFHA × eventTRUE				-0.023
				(0.096)
Num.Obs.	298674	298674	666566	666566
R2	0.856	0.856	0.860	0.860
R2 Within	0.000	0.001	0.002	0.002
RMSE	0.33	0.33	0.32	0.32
Std.Errors	by: pin10	by: pin10	by: pin10	by: pin10
FE: pin	X	X	X	X
FE: sale_year	X	X	X	X
FE: qtr	X	X	X	X