Below is a tool you can use to explore the ideal points of candidates for the State of Texas’s thirty six seats in the U.S. House in the 2014 elections, as depicted by the CFscores model. Click or touch a district to see the modeled ideal points of all the candidates in the 2014 election for the seat representing that district, along with marks that designate the 0-point, which candidate won the seat and which candidate was the most moderate. You can pan the map by dragging and zoom the map by double-clicking, pinching, or mouse-wheeling in order to distinguish the geographically smaller districts in urban regions around cities such as Houston, Dallas and Austin.
click_and_zoom = {//set up containerconst svgHeight =0.3* width;const top = htl.html` <div class="wrapper"> <div class="info"> <div class="info-label"> </div> <div class="info-diagram"> </div> </div> <svg viewBox="0 0 ${width}${svgHeight}" class="map"> </svg> </div> `;//initialize projection and path functionsconst projection = d3.geoAlbersUsa();const path = d3.geoPath().projection(projection);//set scale and center projection.scale(1).translate([0,0]);const b = path.bounds(districts);const s =0.95/Math.max((b[1][0] - b[0][0]) / width, (b[1][1] - b[0][1]) / svgHeight);const t = [ (width - s * (b[1][0] + b[0][0])) /2, (svgHeight - s * (b[1][1] + b[0][1])) /2 ]; projection.scale(s).translate(t);let svgMap = d3.select(top).select("svg.map").on("click",function () { d3.select(top).select("div.info-label").text("Click or touch a district for info"); svgMap.selectAll("path").attr("class","district"); d3.select(top).select("div.info-diagram").html(""); });let map = svgMap.append("g");//draw the districts map.selectAll("path").data(districts.features).enter().append("path").attr("d", path).attr("id", (d) => d.properties.district).attr("class","district").on("click",function (evt, d) { d3.selectAll("path").attr("class","district"); d3.select(this).attr("class","selected"); d3.select(top).select("div.info-label").text(d.properties.district); d3.select(top).select('div.info-diagram').html(''); d3.select(top).select("div.info-diagram").append(() =>spatialDetails(can_by_district.get(d.properties.district))); evt.stopPropagation(); });//initialize the info box d3.select(top).select("div.info-label").text("Click or touch a district for info");//zoom svgMap.call( d3.zoom().extent([ [0,0], [width, svgHeight] ]).scaleExtent([1,8]).on("zoom", zoomed) );functionzoomed({ transform }) { map.attr("transform", transform); }return top;}
Instructions
Identify two districts that show a substantial and obvious contrast in the scope of reduction in polarization made possible by the first filter. More specifically, in one of the two districts you identify, the most moderate candidate should be substantially more moderate than the winning candidate, while in the other district the most moderate candidate should be (relative to the first district) not much more moderate than the winning candidate.
Then, as in the lesson’s analysis of New York’s 4th and 18th districts:
By taking screenshots and then adding text and arrows to those screenshots, or by producing your own hand-drawn or computer-generated diagrams, create marked-up diagrams that show the ideal points of the candidates in the two districts you’ve selected and that point out how much closer the most-moderate candidate in each district is relative to the winning candidate, as a rough percentage of the winning candidate’s distance from the 0-point.
Write several sentences of double spaced text in which you specify which of the two districts had the greater scope for reduction in polarization, and state how much closer to the 0-point the most moderate candidate in each district appears to be relative to the winning candidate, as a rough percentage of the winning candidate’s distance from the 0-point.
Rubric
You can earn up to four points on this COU, 2 points for part (a) and two points for part (b).
For part (a)…
You get two points if…
You provide one diagram for each district, the two diagrams in fact show two districts that differ in the scope of reduction in polarization made possible by the first filter, and each diagram does ALL of the following:
Shows the ideal points of all the candidates for that district, positioned at the same relative distances and directions from the 0 point as displayed by the tool above;
Labels those ideal points with the names of the candidates;
Marks the 0-point;
Distinguishes the ideal points of the winning and most-moderate candidates with marks such as “W” and “M”;
Add distance markers showing the distances from the most-moderate candidate to the 0-point and the winning candidate to the 0-point;
Adds text that points out how much closer the most-moderate candidate is to the 0-point than the winning candidate, as an apparent rough percentage of the winning-candidate’s distance from the 0-point.
You get one point if…
Your diagrams roughly reproduce the positions of the candidates in the two districts you’ve selected, and those two districts in fact differ in the scope of reduction in polarization made possible by the first filter, but either the difference in the scope of reduction in polarization between the two districts is not substantial and obvious, relative to the range of differences one can find across districts using the tool OR you miss one or more of criteria 1 through 6 above (BUT NOT BOTH).
You get zero points if…
You don’t meet the criteria for one point or two points above.
For part (b)…
You get 2 points you got 2 points on part (a) and what you write correctly identifies which district had the greater scope for reduction in polarization and what you write gives rough estimates of the distance from the most moderate candidate to the zero point as a percentage of the distance from the winning candidate to the zero point in each district. No partial credit is available on part (b).