1 Supplemental Information

This document represents additional information about the data and results. The full code and detailed explanation of the figures can be found at the GitHub repository.

1.1 Exploratory analysis

The processed data were explored to characterize and summarize the relevant features, which can be found below.

Table ?? reflects the results of the exploratory data analysis. Between February 2012 and November 2021, there were 446 disaster declarations for states and territories. Funds requested by states or territories for FEMA ranged from -$855,200.3 to $4,388,540,486, with an average of $29,673,687, and FEMA funds obligated to the states and territories after reconciliation ranged from -$855,200.3 to $440,842,4297 with an average of $29,744,109.

Overall
(N=326)
Requested FEMA Funds
Mean (SD) 40600000 (255000000)
Median [Min, Max] 420000 [0.000000000000455, 4390000000]
Obligated FEMA Funds
Mean (SD) 40700000 (256000000)
Median [Min, Max] 434000 [0.000000000000455, 4410000000]
Average FEMA Cost Share
Mean (SD) 0.964 (0.0573)
Median [Min, Max] 1.00 [0.675, 1.00]
Federal Agencies Involved
Mean (SD) 6.23 (7.03)
Median [Min, Max] 3.00 [1.00, 55.0]
Percent of Counties Awarded IH
Mean (SD) 0.338 (1.59)
Median [Min, Max] 0.00197 [0, 27.7]
Percent of Counties Awarded PA
Mean (SD) 0.594 (1.56)
Median [Min, Max] 0.357 [0, 27.3]
Percent of Counties Awarded HM
Mean (SD) 0.476 (1.56)
Median [Min, Max] 0.207 [0, 27.3]
Response Duration (days)
Mean (SD) 1400 (898)
Median [Min, Max] 1180 [70.0, 3590]
Incident Duration (days)
Mean (SD) 136 (250)
Median [Min, Max] 14.0 [0, 660]
Declaration Month
January 71 (21.8%)
February 22 (6.7%)
March 22 (6.7%)
April 24 (7.4%)
May 22 (6.7%)
June 25 (7.7%)
July 13 (4.0%)
August 32 (9.8%)
September 31 (9.5%)
October 41 (12.6%)
November 9 (2.8%)
December 14 (4.3%)
Incident Year
Mean (SD) 2020 (2.89)
Median [Min, Max] 2020 [2010, 2020]
Incident Type
Biological 60 (18.4%)
Earthquake 4 (1.2%)
Fire 20 (6.1%)
Flood 61 (18.7%)
Hurricane 73 (22.4%)
Other 15 (4.6%)
Severe Ice Storm 4 (1.2%)
Severe Storm(s) 82 (25.2%)
Tornado 7 (2.1%)
Declaration Type
DR 261 (80.1%)
EM 65 (19.9%)
FEMA Region
Region I 27 (8.3%)
Region II 19 (5.8%)
Region III 25 (7.7%)
Region IV 62 (19.0%)
Region IX 31 (9.5%)
Region V 37 (11.3%)
Region VI 54 (16.6%)
Region VII 20 (6.1%)
Region VIII 24 (7.4%)
Region X 27 (8.3%)
Counties per State
Mean (SD) 75.3 (53.5)
Median [Min, Max] 67.0 [1.00, 254]
State Population
Mean (SD) 9310000 (10300000)
Median [Min, Max] 5710000 [577000, 39500000]
Figure 1.1 shows the FEMA Regions by state.
FEMA Regions

Figure 1.1: FEMA Regions

Figure 1.2 shows the number of disaster declarations per year, and Figure 1.3 shows the total FEMA funds (both requested and obligated) by states per year. The substantial peak in 2020 corresponds to the COVID-19 pandemic, and the one in 2017 represents the hurricane season with Hurricanes Irma, Harvey, and Maria. These characteristics can also be seen in Table 1.1, which represents FEMA Funding for the 3 Costliest Years (2012 - 2021).

Number of disaster declarations per year 2012 - 2021

Figure 1.2: Number of disaster declarations per year 2012 - 2021

State or territory requested FEMA funds and obligated FEMA funds by year 2012 - 2021

Figure 1.3: State or territory requested FEMA funds and obligated FEMA funds by year 2012 - 2021

Table 1.1: Table 2. FEMA Funding for the 3 Costliest Years (2012 - 2021)
Variable Year
2012, N = 331 2017, N = 361 2020, N = 851
Requested Funds 11,106,321 (55,959,108) 155,310,630 (735,733,161) 74,188,913 (115,267,136)
Obligated Funds 11,388,973 (56,050,414) 155,887,178 (739,000,529) 74,194,235 (115,269,357)

1 Mean (SD)

Figure 1.4 shows the number of disaster declarations per month, and Figure 1.5 shows the total FEMA funds (both requested and obligated) by states per month. The substantial peak in January likely corresponds to the COVID-19 pandemic, and the ones in August, September, and October represent the peak hurricane season. These characteristics can also be seen in Table 1.2, which represents FEMA Funding for the 3 Costliest Months.

Number of disaster declarations per month for years 2012 - 2021

Figure 1.4: Number of disaster declarations per month for years 2012 - 2021

State or territory requested FEMA funds and obligated FEMA funds by month for 2012 - 2021

Figure 1.5: State or territory requested FEMA funds and obligated FEMA funds by month for 2012 - 2021

Table 1.2: Table 3. FEMA Funding for the 3 Costliest Months (2012 - 2021)
Variable Month
Jan1 Sept1 Oct1
Requested Funds 63,229,783 (111,136,115) 100,831,890 (639,779,995) 22,992,573 (101,460,411)
Obligated Funds 63,239,449 (111,135,744) 101,252,822 (642,677,256) 23,165,582 (101,470,263)

1 Mean (SD)

All 50 states as well as Washington, DC were included in the final, combined dataset. Table 1.3 provides the five most disaster-prone states and summarizes their requested FEMA funding and received FEMA funding over the study period.

Table 1.3: Table 4. FEMA Funding for 5 Most Disaster-Prone States 2012 - 2021
Variable State SD, N = 101 TX, N = 161 WA, N = 111 WV, N = 101
CA, N = 191 FL, N = 131 LA, N = 161 MN, N = 101 OK, N = 101
Requested Funds 65,900,489 (173,898,625) 37,851,532 (78,320,708) 47,187,723 (104,127,805) 4,758,425 (13,184,247) 6,413,888 (14,086,311) 2,727,818 (7,026,623) 48,019,502 (135,429,624) 14,599,599 (47,096,442) 10,655,340 (32,155,687)
Obligated Funds 65,900,489 (173,898,625) 37,851,532 (78,320,708) 47,187,723 (104,127,805) 4,758,425 (13,184,247) 6,413,888 (14,086,311) 2,727,818 (7,026,623) 48,087,226 (135,451,571) 14,599,599 (47,096,442) 10,656,415 (32,155,346)

1 Mean (SD)

Incident duration ranged from zero days to 660 days (or almost two years), as seen by Figure 1.6. The incident duration of 660 days likely corresponds to the COVID-19 pandemic, which is an ongoing incident of almost two years. Further analysis of all variables can be found in the supplementary information.

Incident duration for requested FEMA funds and obligated FEMA funds under $1 billion for 2012 - 2021

Figure 1.6: Incident duration for requested FEMA funds and obligated FEMA funds under $1 billion for 2012 - 2021

1.2 Modeling Analysis

Prior to fitting the data to machine learning models, standard simple and multivariable regression models were fitted using the tidymodels framework in RStudio 4.1. Both outcomes of interest were fitted, using incident duration as the primary predictor of interest. Figure @ref(fig:req_MVR_bp) and @ref(fig:obl_MVR_bp) show the significant variables fitted in the multivariable regression models for requested and obligated FEMA funds, respectively. There are simply too many variables to be able to report all variables on one figure.

Significant predictors in multivariate regression model for requested FEMA funds

(#fig:req_MVR_bp)Significant predictors in multivariate regression model for requested FEMA funds

Significant predictors in multivariate regression model for obligated FEMA funds

(#fig:obl_MVR_bp)Significant predictors in multivariate regression model for obligated FEMA funds

Table 1.4 shows the comparisons of the models, using the root mean square error (RMSE) and r-squared statistics. The requested and obligated funding models performed almost identically. None of the models fit the data well, which suggests more sophisticated modeling practices are necessary to adequately characterize the data.

Table 1.4: Linear model comparisons
Obligated Requested
MVR: rmse 3.2825340 3.2821346
MVR: rsq 0.5767613 0.5765888
SLR: rmse 4.6045374 4.6012644
SLR: rsq 0.1672034 0.1678456

1.3 Machine Learning Models

The identified decision tree model for each outcome is illustrated by Figures 1.7 and 1.8.

Selected decision tree for predicting requested FEMA funds

Figure 1.7: Selected decision tree for predicting requested FEMA funds

Selected decision tree for predicting obligated FEMA funds

Figure 1.8: Selected decision tree for predicting obligated FEMA funds

The most important variables in the identified random forest model for each outcome is illustrated by Figures 1.9 and 1.10.

20 most important variables for the random forest model for requested FEMA funds

Figure 1.9: 20 most important variables for the random forest model for requested FEMA funds

20 most important variables for the random forest model for obligated FEMA funds

Figure 1.10: 20 most important variables for the random forest model for obligated FEMA funds

The most important variables in the identified elastic net model for each outcome is illustrated by Figures 1.11 and 1.12.

20 most important variables for the elastic net model for requested FEMA funds

Figure 1.11: 20 most important variables for the elastic net model for requested FEMA funds

20 most important variables for the elastic net model for obligated FEMA funds

Figure 1.12: 20 most important variables for the elastic net model for obligated FEMA funds

The most important variables in the identified LASSO model for each outcome is illustrated by Figures 1.13 and 1.14.

20 most important variables for the LASSO model for requested FEMA funds

Figure 1.13: 20 most important variables for the LASSO model for requested FEMA funds

20 most important variables for the LASSO model for obligated FEMA funds

Figure 1.14: 20 most important variables for the LASSO model for obligated FEMA funds

Table 1.5 shows the model comparisons for estimating requested FEMA funding, and Table 1.6 similarly shows the model comparisons for estimating obligated FEMA funding.

Table 1.5: ML model comparison for requested FEMA funding
rmse SE model
5.388000 2.3019 LASSO
5.394000 2.3023 EN
5.552000 2.2316 RF
5.679000 2.1802 Tree
5.276854 0.0000 Null - Train
Table 1.6: ML model comparison for obligated FEMA funding
rmse SE model
5.38900 2.3020 LASSO
5.39500 2.3023 EN
5.55200 2.2302 RF
5.70700 2.1712 Tree
5.27838 0.0000 Null - Train

Once the random forest was fit to the test data, the following diagnostic plots were created for each outcome.

For Requested FEMA Funding:
Actual vs predicted log(requested FEMA funds) for the random forest test model

Figure 1.15: Actual vs predicted log(requested FEMA funds) for the random forest test model

Requested FEMA funds residuals for the random forest test model

Figure 1.16: Requested FEMA funds residuals for the random forest test model

Residuals versus fitted values of the log(requested FEMA funds) for the random forest test model

Figure 1.17: Residuals versus fitted values of the log(requested FEMA funds) for the random forest test model

For Obligated FEMA Funding:

Actual vs predicted log(obligated FEMA funds) for the random forest test model

Figure 1.18: Actual vs predicted log(obligated FEMA funds) for the random forest test model

Obligated FEMA funds residuals for the random forest test model

Figure 1.19: Obligated FEMA funds residuals for the random forest test model

Residuals versus fitted values of the log(obligated FEMA funds) for the random forest test model

Figure 1.20: Residuals versus fitted values of the log(obligated FEMA funds) for the random forest test model