The following is a look at COVID-19 Cases & Deaths data from the New York Times since stay-at-home orders were imposed (or since April 1st if they weren’t). The dates and details of stay-at-home orders and their lifting are from the Washington Post article “Where states are reopening after America’s shutdown”.
Pettit’s Test (a statistical test for changes in trend) trend::pettit.test
is performed on each set of data to determine where there is a shift in trend (if any). The results of this test are in the captions at the base of each graph and the blue vertical line indicates the date on which the shift in trend occurred according to the test.
Graph Legend
One of the most notable graphs is that of Minnesota. We’ll use it as an example for the descriptions below:
The lower most graph depicts raw cases/deaths:
- The beginning and end of stay-at-home orders are depicted by labeled vertical lines where applicable, with the corresponding dates.
- Linear regression is performed on the before & after lifting restrictions (or all the data if restrictions were not lifted). The slope of the line is printed near the line as
B: ...
. These can be compared to the linear regression of all the data to illustrate deviation from the overall trajectory.
The middle graph shows daily new cases/deaths:
- A loess regression illustrates whether there was a flux in these numbers after lifting restrictions.
- A horizontal line is drawn at the mean before & after restrictions lift for states where restrictions are lifted, additionally a Tukey boxplot shows the median and quartiles.
- The p.value of the T.test comparing the before & after data is plotted near the top.
The top graph shows the proportion/percent change in daily new cases/deaths. IE the change in the rate of infection:
- A loess regression illustrates whether there was a flux in these numbers after lifting restrictions.
- A horizontal line is drawn at the mean before & after restrictions lift for states where restrictions are lifted, additionally a Tukey boxplot shows the median and quartiles.
- The p.value of the T.test comparing the before & after data is plotted near the top.
Table of Contents
Legend
- State = State-name
- Is Open? = Logical indicating whether the state has lifted or never imposed restrictions
- Date_lifted = The date restrictions were lifted (if they were imposed)
- *D_pv = The p-value of the t-test comparing daily new cases/deaths before and after restrictions were lifted,
- *D_dm = The difference in means (after - before) of daily new cases/deaths.
- *%_pv = The p-value of the t-test comparing the rate of change in daily new cases/deaths before and after restrictions were lifted,
- *%_dm= The difference in means (after - before) of the rate of change in daily new cases/deaths before and after restrictions were lifted,
- Open = If restrictions were imposed and lifted, what types of establishments and activities are re-opened,
- Closed = If restrictions were imposed and lifted, what types of establishments and activities are still restricted.
The table makes it possible to compare the types of restrictions being lifted in states and whether lifting restrictions on those types of establishments is leading to a statistically significant change (the p-value) in the number of cases/deaths, and in what direction the change is occurs (the difference in means).
Alabama
Open: Gyms, personal-care businesses such as salons, barbershops, restaurant, bar dine-in services, beaches, retail stores
Closed: Nightclubs, movie theaters, concert, sporting venues
Alaska
Open: Places of worship, bars, restaurant dine-in services, theaters, retail stores, gyms, personal-care businesses such as salons, barbershops
Closed:
Arizona
Open: Elective surgeries, casinos, gyms, major league sports without fans, restaurant dine-in services, retail stores, personal-care businesses such as salons, barbershops
Closed: Bars, nightclubs
Arkansas
Open: Outdoor recreation, bars, restaurant dine-in services, bars, gyms, personal-care businesses such as salons, barbershops, Movie theaters, concert, sporting venues
Closed:
California
Open: Lower-risk businesses including bookstores, florists, clothing stores, Personal-care businesses such as salons, barbershops in most of the state
Closed: Gyms, restaurant dine-in services, bars, nightclubs, movie theaters, concert, sporting venues
Colorado
Open: Campgrounds at some state parks, gyms, restaurant dine-in services, retail stores, personal-care businesses such as salons, barbershops
Closed: Bars, nightclubs, movie theaters, concert, sporting venues
Connecticut
Open: Restaurants for outdoor seating, personal-care businesses such as salons, barbershops, retail stores, offices, outdoor museums, zoos
Closed: Bars, nightclubs, movie theaters, concert, sporting venues
Delaware
Open: Gyms; retail businesses; personal-care businesses such as barbershops, salons are by appointment only, Restaurants for dine-in services by reservation only, Beaches, community pools
Closed: Bars, nightclubs, movie theaters, concert, sporting venues
Florida
Open: Retail stores, restaurant dine-in services, personal-care businesses such as salons, barbershops, Bars in most of the state, Gyms, outdoor recreation, Sporting venues may operate without spectators
Closed: Bars, nightclubs, movie theaters, concert venues
Georgia
Open: Outdoor recreation, gyms, personal-care businesses such as salons, barbershops, theaters, restaurant dine-in services, Bars, nightclubs
Closed: Live performance venues
Hawaii
Open: Retail businesses such as shopping malls, pet groomers, carwashes, Nonprofit organizations, Outdoor recreation
Closed: Restaurant dine-in services, Beaches can be used only for exercise
Idaho
Open: Restaurant dine-in services, gyms, personal-care businesses such as salons, barbershops, places of worship, some retail stores, Bars, nightclubs, large venues such as movie theaters, concert, sporting venues
Closed:
Illinois
Open: State parks, personal-care businesses such as salons, barbershops, golf courses, retail stores
Closed: Gyms, restaurant dine-in services, bars, nightclubs, large venues such as movie theaters, concert, sporting venues
Indiana
Open: Retail stores, bars, nightclubs, gyms, movie theaters, offices, places of worship, restaurant dine-in service, personal-care businesses such as salons, barbershops
Closed: Conventions, fairs, festivals, parades
Iowa
Open: Outdoor recreation, gyms, bars, restaurant dine-in service, retail stores, personal-care businesses such as salons, barbershops
Closed: Nightclubs, concert, sporting venues