Principal Web Developer at Freedom of the Press Foundation
Beantown Stomp 2023 CO₂ LevelsAssorted CO₂ ReadingsNYC SARS-CoV-2 Wastewater DataAranet4 Data UtilitiesFreedom of the Press Foundation 2022 All Staff CO₂ LevelsCO₂ Measurements for ESCape at Pinewoods Camp 2022Boston-Area SARS-CoV-2 Wastewater LevelsCharting a Case Fatality Rate by WaveWhich states’ worst pandemic days were this week?Covid Cases vs. Deaths and HospitalizationsU.S. Air Travel in a PandemicMassachusetts COVID DataMassachusetts Coronavirus Cases by TownCOVID-19 Infection and Fatality by RaceWhere is COVID-19 rising and falling in the U.S.?How many SARS-CoV-2 tests are we running in the U.S.?
Charting a Moving Case Fatality Rate
statesSummary = d3.csv(`https://api.covidactnow.org/v2/states.csv?apiKey=${API_KEY}`)
data = d3.csv(`https://api.covidactnow.org/v2/states.timeseries.csv?apiKey=${API_KEY}`, d3.autoType)
selectedStateData = data.filter(d => d.state === state).filter(d => d.date > d3.timeParse('%Y-%m-%d')(startDate))
blur = arr => ArrayBlur.blur().radius(blurRadius)(arr)
blurredCases = blur(selectedStateData.map(d => d['actuals.newCases']))
blurredDeaths = blur(selectedStateData.map(d => d['actuals.newDeaths']))
annotatedStateData = selectedStateData
.map((d, i, arr) => ({
date: d.date,
newCases: d['actuals.newCases'],
newDeaths: d['actuals.newDeaths'],
newCasesSmooth: blurredCases[i],
newDeathsSmooth: blurredDeaths[i],
casePeak: blurredCases[i - 1] < blurredCases[i] && blurredCases[i + 1] < blurredCases[i],
deathPeak: blurredDeaths[i - 1] < blurredDeaths[i] && blurredDeaths[i + 1] < blurredDeaths[i],
caseValley: blurredCases[i - 1] > blurredCases[i] && blurredCases[i + 1] > blurredCases[i],
deathValley: blurredDeaths[i - 1] > blurredDeaths[i] && blurredDeaths[i + 1] > blurredDeaths[i],
vaccinesInitiatedRatio: d['metrics.vaccinationsInitiatedRatio'],
vaccinesCompletedRatio: d['metrics.vaccinationsCompletedRatio'],
}))
.map((d, i, arr) => ({
...d,
// Find the next death peak data point and record it's index in the dataset
nextDeathPeakIdx: (
arr.slice(i).findIndex(d => d.deathPeak) !== -1 ?
i + arr.slice(i).findIndex(d => d.deathPeak) :
null
),
nextDeathValleyIdx: (
arr.slice(i).findIndex(d => d.deathValley) !== -1 ?
i + arr.slice(i).findIndex(d => d.deathValley) :
null
)
}))
.map((d, i, arr) => ({
...d,
// Fetch the next death peak's date
nextDeathPeak: (
d.nextDeathPeakIdx ?
arr[d.nextDeathPeakIdx].date :
null
),
nextDeathValley: (
d.nextDeathValleyIdx ?
arr[d.nextDeathValleyIdx].date :
null
)
}))
.map((d, i, arr) => ({
...d,
// Calculate the time in days until the next death peak
daysTillNextDeathPeak: (
d.nextDeathPeak ?
d3.timeDay.range(d.date, d.nextDeathPeak).length :
null
),
// Calculate the time in days until the next death valley
daysTillNextDeathValley: (
d.nextDeathValley ?
d3.timeDay.range(d.date, d.nextDeathValley).length :
null
)
}))
validPeakPair = d => (
(
// Make sure this point is a case peak and there's a death peak after it
d.casePeak &&
d.nextDeathPeak &&
// Exclude peaks that seem either too soon or too late to be related
d.daysTillNextDeathPeak > minPeakDelay &&
d.daysTillNextDeathPeak < maxPeakDelay
) || (
// Make sure this point is a case valley and there's a death valley after it
d.caseValley &&
d.nextDeathValley &&
// Exclude valleys that seem either too soon or too late to be related
d.daysTillNextDeathValley > minPeakDelay &&
d.daysTillNextDeathValley < maxPeakDelay
)
)
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