July 8, 2020 Analysis of USA state data

Summary

usa

The histogram shows the daily cases for the 50 states and DC. The curve labelled “no change” shows the expected daily cases by adding the expectations from all of the individual state models fit to the state data, as shown below. Also shown are projections, if measures are taken to reduce transmission rates, back to April 15 or May 15 levels, with the public policy change being made on July 22 or August 1. Model fits use data March 1 - July 19.

Individual state fits

The plots below show the case / hospitalization / deaths data for all 50 states and DC. The infection trajectory is determined by fits to the cumulative case data. For most states, case data can be well described by a constant transmission rate since Memorial day weekend (day 84).

The red curves (contagious population) is the inferred contagious population. Its shape is determined from the case data. Its scale is not well known.

The data fits were done using data up until July 7.

Alaska

Alabama

Arkansas

Arizona

California

Colorado

Connecticut

District Of Columbia

Delaware

Florida

Georgia

Hawaii

Iowa

Idaho

Illinois

Indiana

Kansas

Kentucky

Louisiana

Massachusetts

Maryland

Maine

Michigan

Minnesota

Missouri

Mississippi

Montana

North Carolina

North Dakota

Nebraska

New Hampshire

New Jersey

New Mexico

Nevada

New York

Ohio

Oklahoma

Oregon

Pennsylvania

Rhode Island

South Carolina

South Dakota

Tennessee

Texas

Utah

Virginia

Vermont

Washington

Wisconsin

West Virginia

Wyoming

Tables

The tables below are results from the fits to reference model 2.3. These are shown for purposes of comparison.

Daily fractional growth rates (δ)

state	δ₀	day 1	δ₁	day 2	δ₂	day 3	δ₃	day 4	δ₄
AL	0.102 +/- 0.009	32	0.007 +/- 0.002	84	0.030 +/- 0.002
AR	0.090 +/- 0.010	34	-0.041 +/- 0.014	84	0.028 +/- 0.003
AZ	0.051 +/- 0.008	26	0.034 +/- 0.002	84	0.056 +/- 0.003
CA	0.172 +/- 0.011	27	0.010 +/- 0.001	84	0.035 +/- 0.001
CO	0.151 +/- 0.014	24	0.011 +/- 0.006	44	-0.020 +/- 0.004	74	-0.021 +/- 0.006	84	-0.004 +/- 0.004
CT	0.254 +/- 0.019	24	0.056 +/- 0.005	38	-0.021 +/- 0.001	84	-0.053 +/- 0.004
DC	0.185 +/- 0.019	27	0.016 +/- 0.006	50	-0.020 +/- 0.002	84	-0.035 +/- 0.002
DE	0.205 +/- 0.012	29	0.033 +/- 0.004	49	-0.001 +/- 0.003	71	-0.044 +/- 0.008	99	0.053 +/- 0.008
FL	0.217 +/- 0.015	25	-0.014 +/- 0.002	63	0.006 +/- 0.003	84	0.077 +/- 0.002
GA	0.228 +/- 0.015	27	-0.006 +/- 0.001	84	0.043 +/- 0.002
HI	0.159 +/- 0.021	26	-0.074 +/- 0.015	84	0.048 +/- 0.015
IA	0.232 +/- 0.009	22	0.069 +/- 0.004	55	-0.019 +/- 0.001	84	0.010 +/- 0.002
ID	0.259 +/- 0.018	24	-0.044 +/- 0.008	49	-0.008 +/- 0.007	84	0.080 +/- 0.004
IL	0.162 +/- 0.010	26	0.032 +/- 0.002	60	-0.016 +/- 0.001	84	-0.077 +/- 0.004	95	0.006 +/- 0.003
IN	0.230 +/- 0.022	25	0.011 +/- 0.002	55	-0.014 +/- 0.002	84	-0.003 +/- 0.003
KS	0.154 +/- 0.020	25	0.035 +/- 0.016	41	-0.000 +/- 0.008	84	0.035 +/- 0.008
KY	0.235 +/- 0.021	22	0.058 +/- 0.007	40	0.004 +/- 0.003	84	0.007 +/- 0.004
LA	0.267 +/- 0.013	26	-0.047 +/- 0.004	50	0.013 +/- 0.004	84	0.052 +/- 0.003
MA	0.159 +/- 0.014	28	0.033 +/- 0.004	46	-0.028 +/- 0.002	84	-0.045 +/- 0.002
MD	0.131 +/- 0.006	34	0.015 +/- 0.001	74	-0.027 +/- 0.002	110	0.003 +/- 0.016
ME	0.221 +/- 0.073	16	0.011 +/- 0.005	84	-0.012 +/- 0.005
MI	0.112 +/- 0.005	20	-0.012 +/- 0.001	71	-0.054 +/- 0.005	94	0.044 +/- 0.005
MN	0.101 +/- 0.016	19	0.053 +/- 0.006	47	0.014 +/- 0.002	76	-0.052 +/- 0.003	95	0.025 +/- 0.003
MO	0.207 +/- 0.032	25	-0.006 +/- 0.004	84	0.032 +/- 0.003
MS	0.118 +/- 0.008	34	0.004 +/- 0.004	84	0.027 +/- 0.002
MT	0.179 +/- 0.033	23	-0.054 +/- 0.020	37	-0.097 +/- 0.045	84	0.080 +/- 0.013
NC	0.122 +/- 0.017	24	0.027 +/- 0.001	84	0.021 +/- 0.001
ND	0.289 +/- 0.108	22	-0.040 +/- 0.004	84	0.001 +/- 0.004
NE	0.196 +/- 0.024	25	0.094 +/- 0.034	53	-0.015 +/- 0.005	84	-0.016 +/- 0.004
NH	0.168 +/- 0.029	28	0.007 +/- 0.010	84	-0.044 +/- 0.020
NJ	0.217 +/- 0.006	25	-0.001 +/- 0.001	49	-0.038 +/- 0.001	84	-0.025 +/- 0.002
NM	0.153 +/- 0.024	30	0.025 +/- 0.009	59	-0.010 +/- 0.005	84	0.011 +/- 0.005
NV	0.318 +/- 0.042	21	-0.004 +/- 0.004	84	0.060 +/- 0.003
NY	0.243 +/- 0.008	20	0.020 +/- 0.002	36	-0.039 +/- 0.000	84	-0.016 +/- 0.002
OH	0.267 +/- 0.031	23	-0.005 +/- 0.008	50	-0.011 +/- 0.002	84	0.019 +/- 0.002
OK	0.226 +/- 0.039	24	-0.002 +/- 0.003	84	0.053 +/- 0.003
OR	0.096 +/- 0.022	25	0.000 +/- 0.006	84	0.048 +/- 0.003
PA	0.343 +/- 0.017	22	0.088 +/- 0.012	32	-0.014 +/- 0.001	84	-0.042 +/- 0.005	98	0.030 +/- 0.004
RI	0.170 +/- 0.008	34	0.028 +/- 0.009	48	-0.024 +/- 0.005	84	-0.039 +/- 0.009
SC	0.266 +/- 0.031	22	0.012 +/- 0.002	84	0.060 +/- 0.002
SD	0.175 +/- 0.022	38	-0.063 +/- 0.025	49	0.001 +/- 0.012	84	-0.005 +/- 0.029
TN	0.199 +/- 0.038	22	0.008 +/- 0.001	84	0.036 +/- 0.002
TX	0.149 +/- 0.008	29	0.007 +/- 0.001	84	0.057 +/- 0.001
UT	0.135 +/- 0.019	25	0.010 +/- 0.005	73	0.031 +/- 0.002
VA	0.208 +/- 0.011	27	0.037 +/- 0.002	56	0.008 +/- 0.002	84	-0.023 +/- 0.002
VT	0.142 +/- 0.028	25	-0.067 +/- 0.015	84	0.078 +/- 0.036
WA	0.098 +/- 0.011	11	-0.005 +/- 0.001	84	0.024 +/- 0.004
WI	0.208 +/- 0.019	24	-0.027 +/- 0.003	84	0.008 +/- 0.002
WV	0.216 +/- 0.045	25	-0.021 +/- 0.010	84	0.049 +/- 0.014
WY	0.179 +/- 0.045	23	-0.031 +/- 0.057	51	-0.026 +/- 0.020	84	0.042 +/- 0.011

δ₀: initial daily fractional growth parameter
day 1: days after March 1, 2020 when transmission rate changed
transition day 84 (May 23) forced: used to estimate growth following Memorial day weekend

Infection status

The following plots summarize the infection history. The upper plot shows the daily growth/decline from the fit. Bands show approximate 95% CL intervals. The lower plot shows the size of the infection: the uncorrected circulating contagious population per million.