bar + scatter

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/crossfilter/1.3.12/crossfilter.min.js">
</script>

<style>

body {
  font: 10px sans-serif;
}

div.tooltip {
  position: absolute;
  text-align: center;
  width: 90px;
  height: 30px;
  padding: 2px;
  font: 12px sans-serif;
  background: lightsteelblue;
  border: 0px;
  border-radius: 8px;
}
.hidden {
  display: none;
}
  
.axis path,
.axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}

.bar
  	
.x.axis path {
  display: none;
}

</style>
</head>

var yscale = d3.scaleLinear()
  			.range([height,0]);
    
    var svg1 = d3.select('#container').append("svg")
    .attr('id','bar')
    .attr("width", (width + margin.left + margin.right)/2)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", 
          "translate(" + margin.left + "," + margin.top + ")");
    
    var svg2 = d3.select('#container').append("svg")
    .attr('id','scatter')
    .attr("width", (width + margin.left + margin.right)/2)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", 
          "translate(" + margin.left + "," + margin.top + ")");	
    
    var tooltip = d3.select('#container').append('div')
    .attr('class', 'hidden tooltip')
    .style("opacity", 0);
    
function createbar(data){

var ndx = crossfilter(data);

var raceethnicity = ndx.dimension(function(d) { return [d["raceethnicity"]]; })
  
  var raceethnicityGroup = raceethnicity.group().reduceCount(function(d) {
    return d.raceethnicity;
  });

//horizontal line
			svg2
				.append("line")
				.attr("class", "guide")
				.attr("x1", 0)
				.attr("x2", xscale(d.key[1]))
				.attr("y1", yscale(d.value))
				.attr("y2", yscale(d.value))
				.style("stroke", color(d.key[0]))
				.style("opacity", 0)
				.transition().duration(200)
				.style("opacity", 0.8);
      
      //Value on the axis
			svg2
				.append("text")
				.attr("class", "guide")
				.attr("x", 13)
				.attr("y", yscale(d.value)+8)
				.attr("dy", "0.35em")
				.style("fill", color(d.key[0]))
				.style("opacity", 0)
				.style("text-anchor", "end")
				.text(d.value)
				.transition().duration(200)
				.style("opacity", 0.8);

tooltip.classed('hidden', false)
         .transition()
         .duration(200)
         .style("opacity", .9);
      
       tooltip.html(d.key[0])     
         .style("left", (d3.event.pageX) + "px")             
         .style("top", (d3.event.pageY - 28) + "px");
       })
    
    .on("mouseout", function() {
      		//remove guide
          d3.selectAll(".guide")
          	.classed('hidden', true);
					//Remove the tooltip
					tooltip.classed('hidden', true);					
			   })
    .filter(function(d) { return d.value == 0; })
    .style("opacity", 0);

//legend
  	var legend = svg2.selectAll(".legend")
      .data(color.domain())
    .enter().append("g")
      .attr("class", "legend")
      .attr("transform", function(d, i) { return "translate(2," + i * 14 + ")"; });
	
		legend.append("rect")
      .attr("x", width)
      .attr("width", 12)
      .attr("height", 12)
      .style("fill", color);

legend.append("text")
      .attr("x", width + 16)
      .attr("y", 6)
      .attr("dy", ".35em")
      .style("text-anchor", "start")
      .text(function(d) { return d; });

legend.on("mouseover", function(type) {
      d3.selectAll(".legend")
        .style("opacity", 0.1);
      d3.select(this)
        .style("opacity", 1);
      d3.selectAll("g.bubble")
        .style("opacity", 0.1)
        .filter(function(d) { return d.key[1] == type; })
        .style("opacity", 1);
    })
    .on("mouseout", function(type) {
      d3.selectAll(".legend")
        .style("opacity", 1);
      d3.selectAll("g.bubble")
        .style("opacity", 1);
    }); 
  
//brush  
  var brush = d3.brushX()
        .extent([[0, 0], [width, height]])
        .on('start brush', function () {
            var s = d3.event.selection,
             x0 = s[0][0],
             x1 = s[0][1];
            //convert into age
          	var min=xscale.invert(s[0])
            var max=xscale.invert(s[1])
						//console.log(min,max)
            var dataset = [
    					{name: 'Arab-American', value: 0},
    					{name: 'Asian/Pacific Islander', value: 0},
    					{name: 'Black', value: 0},
    					{name: 'Hispanic/Latino', value: 0},
    					{name: 'Native American', value: 0},
              {name: 'White', value: 0}
						];
            filteredData.forEach(function(d,i){
    							if (min <= d.key[1] && d.key[1] <= max){
                    for (i = 0; i < dataset.length; i++) { 
                    	if (dataset[i].name==d.key[0]){
                        dataset[i].value+=d.value
                      };
                    };
                  };
            });
          	console.log(dataset);
            /*var key =[];
          	var value=[]
  					filteredData.forEach(function(d,i){
    							if (min <= d.key[1] && d.key[1] <= max){
                    if (d.key[0] in key){
                      var tmp = key.indexOf(d.key[0]);
                      value[tmp]+= d.value
                    }
                    else{
     									key.push([d.key[0]]);
                      value.push(d.value); 
                    }
           
                    
    							}
      					});*/
			
          	
            
  var arc = d3.arc()
      .outerRadius(radius - 10)
      .innerRadius(70);

var pie = d3.pie()
      .sort(null)
      .value(function(d) {
          return d.value;
      });

var path = svg1.selectAll('path')
                .data(pie(value))
                .enter()
                .append('path')
                .attr('d', arc)
                .attr('fill', function(d, i) {
                    return color(d.key);
                })

});
  
  svg2.append('g')
     .attr('class', 'brush')
     .call(brush)
  /*dataf = filteredData.filter(function(d){10 < filteredData[0].key[1]
              &&  filteredData[0].key[1] < 50});*/
 
  //filter data
  /*function onBrush(x0, x1) {
     data.forEach(function (d) {
         d.filtered = clear ? false
             : d.age < x0 || d.age > x1
        })
        console.log(data);
    }*/
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
   };

d3.csv("data.csv", function(error, data) {
  if (error) throw error;
  
  createbar(data)

});
    
  </script>

https://d3js.org/d3.v4.min.js

https://cdnjs.cloudflare.com/ajax/libs/crossfilter/1.3.12/crossfilter.min.js