Vote Cone — UninterpolatedReflecting on “Vote Cones”Vote Cones in Vega-LiteElection 2020: How reliable are different results at different stages?Election 2020 Vote–Time Correlation CartogramElection 2020 Vote Count Speed CartogramElection Cone — Iowa Senate 2016Election Cones — President 2016Election Cones — Senate 2016What’s the connection between these two election bar charts?Election 2020 DataElection 2020 Vote Margin CartogramElection 2020 Cone with Colored ContoursElection 2020 Cone with Labeled ContoursCalculate the percentage of remaining vote needed to overcome given absolute margin
Vote Cone Transitions
update = chart[shape]()
y = d3.scaleLinear([0, 1], [margin.top, height - margin.bottom])
x1 = d3.scaleLinear([0, 1], [margin.left, _width - margin.right])
x2 = d3.scaleLinear(
[-latest.votes, latest.votes],
[margin.left, _width - margin.right]
)
line1 = d3
.line()
.x(d => x1(d.share))
.y(d => y(d.counted))
line2 = d3
.line()
.x(d => x2((2 * d.share - 1) * d.votes))
.y(d => y(d.counted))
margin = ({ top: 10, right: 15, bottom: 30, left: 40 })
_width = Math.min(640, width)
height = _width - margin.left - margin.right + margin.top + margin.bottom
range = ([a, b], step) => [...d3.range(a, b, step), b]
rep = Object.assign(
raceData.candidates.find(d => d.party_id === "republican"),
{ color: "#dd2c35" }
)
dem = Object.assign(raceData.candidates.find(d => d.party_id === "democrat"), {
color: "#0080c9"
})
raceData = presidentByState.get(state_id)
timeseries = raceData.timeseries
.map(d => ({
share:
d.vote_shares[rep.candidate_key] /
(d.vote_shares[rep.candidate_key] + d.vote_shares[dem.candidate_key]) ||
0.5,
votes: d.votes,
counted: d.eevp / 100,
time: new Date(d.timestamp)
}))
.slice(1)
called = ({
...(raceData.leader_party_id === "democrat" ? dem : rep),
...timeseries.find(d => d.time >= raceData.winnerCalledTimestamp)
})
latest = timeseries[timeseries.length - 1]
// solve for z: z = (x * y - t) / (y - 1)
// solve for y: y = (t - z) / (x - z) and x!=z and t!=x
// solve for x: x = (t + (y - 1) * z) / y and y!=0 and y!=1
// solve for t: t = x y - y z + z and y!=1
contour = z => x => (0.5 - z) / (x - z)
gridlines = d3
.range(0.1, 1, 0.1)
.filter(z => z !== 0.5)
.map(z => ({
z,
data: range([0, 1], 0.02)
.map(d => {
const counted = contour(z)(d);
return { share: d, counted, votes: latest.votes * counted };
})
.filter(({ counted }) => counted >= 0 && counted <= 1)
}))
getEndzone = (domain, step, z) =>
range(domain, step)
.map(d => {
const counted = contour(z)(d);
return { share: d, counted, votes: latest.votes * counted };
})
.concat([{ share: +!z, votes: latest.votes, counted: 1 }])
endzones = [
{ d: getEndzone([0.5, 1], 0.01, 0), fill: rep.color },
{ d: getEndzone([0, 0.5], 0.01, 1), fill: dem.color }
]
field = [
{ share: 0, votes: 0, counted: 0 },
{ share: 1, votes: 0, counted: 0 },
{ share: 1, votes: latest.votes, counted: 1 },
{ share: 0, votes: latest.votes, counted: 1 }
]
yAxis = g =>
g
.attr("transform", `translate(${margin.left}, 0)`)
.call(d3.axisLeft(y).tickFormat(d3.format(".0%")))
.call(g => g.select(".domain").remove())
.call(g =>
g
.select(".tick:first-of-type text")
.clone()
.attr("x", 3)
.attr("text-anchor", "start")
.text("Percent of votes counted in " + raceData.state_name)
)
x1Axis = g =>
g
.attr("transform", `translate(0, ${height - margin.bottom})`)
.call(
d3
.axisBottom(x1)
.ticks(Math.min(width / 40, 10))
.tickFormat(d3.format(".0%"))
)
.call(g => g.select(".domain").remove())
.call(g =>
g
.append("text")
.attr("x", width)
.attr("y", margin.bottom - 4)
.attr("fill", "currentColor")
.attr("text-anchor", "end")
.text("Percent of votes won by " + rep.last_name)
)
x2Axis = g =>
g
.attr("transform", `translate(0, ${height - margin.bottom})`)
.call(
d3
.axisBottom(x2)
.ticks(4)
.tickFormat(d3.format("+.2s"))
)
.call(g => g.select(".domain").remove())
.call(g =>
g
.append("text")
.attr("x", width)
.attr("y", margin.bottom - 4)
.attr("fill", "currentColor")
.attr("text-anchor", "end")
.text("Margin of votes won by " + rep.last_name)
)
d3 = require("d3@6")
import { radio, select } from "@jashkenas/inputs"
import { presidentByState, president } from "1342cadc9354cc67"
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