Unstandardized Choropleth Maps

http://eps.mq.edu.au/courses/GEOS219/choropleth.htm

Unstandardized choropleth maps can be determined by whether or not a map is areally averaged. They don't average or standardize the data.  This example of an unstandardized choropleth map exhibits deaths of babies every 1,000 live births in Australia.  The legend classes from bottom to top read: suppressed, less than 5, 5-6, 6-7, 7-10, 10 or more.

Standardized Choropleth Maps

http://www.statcan.gc.ca/pub/92f0138m/2008003/figures/5200001-eng.htm

Another type of choropleth map, the standardized map's data is conformed to a standard.  The data is areally averaged for more controllable figures.  This standardized choropleth map demonstrates the percentage of population aged 14 and under in Canada by 2006 Census Division.  The map alludes to the fact that the northern territories contain the largest percent of people 14 and under, while the southern areas of Canada that border the United States generally contain an older population.

Bivariate Choropleth Maps

https://www.e-education.psu.edu/geog486/node/1849

The main purpose of a Bivariate chrolopleth map is to display two variables on a single map by combining two different sets of graphic symbols or colors. The bivariate colored rectangle legend in the top right displays how many colors are possibly on the map.  This bivariate choropleth map exhibits the 2008 presidential election between Barack Obama and John McCain by county.  A perfect blend of blue and red is purple, which covers most of the map, telling you it was a close election.

Unclassed Choropleth Maps

http://go.owu.edu/~jbkrygie/krygier_html/geog_353/geog_353_lo/geog_353_lo07.html

Unclassed Choropleth Maps use a continuous grey scale.  There are as many intervals as there are areal units.  Although it doesn't seem there would be many advantages to unclassed choropleth maps, they are good for seeking patterns and minimizes the amount of generalization and simplification.  The unclassed choropleth map above shows population change in the United States from 1960-1970 by county.

Classed Choropleth Maps

http://my.ilstu.edu/~jrcarter/Geo204/Choro/

Classed choropleth maps is a type of choropleth map that is combined into a smaller number of groups and portrayed in intervals.  Typically, four to seven classes are used to display the data.  In the classed choropleth map pictured, there are four classes to represent the amount of males per 100 females in each state in the United States.

Lorenz Curve

http://www.unc.edu/~nielsen/special/s2/s2.htm

A lorenz curve is a graph in which the cumulative percentage of some variable is plotted against the cumulative percentage of the corresponding population.  The extent to which the curve sags below a straight diagonal line indicates the degree of inequality of distribution.  The 45 degree line represents perfect equality so the closer the Lorenz curve is to the 45 degree line, the less the inequality and the smaller the inequality, or Gini coefficient.

Bilateral Graph

http://www.gallup.com/poll/106858/chinas-leadership-better-regarded-outside-west.aspx

A bilateral graph is a visual representation of numerical or other information, often used for comparative purposes.  The graph above is detailing approval rates of the leadership of China.  This bilateral graph is comparing Europe, the Americas, Asia, Middle East/North Africa, and Sub-Saharan Africa.  Immediately, the approval rates in Sub-Saharan Africa jump off the chart.  Highest disapproval rates belong to Middle East/North Africa.  Bilateral graphs facilitate comparisons.