Digital Mapping

Digital Mapping



Digital Mapping

Choropleth map of male unemployment at output area level

Choropleth maps are a type of thematic map in which areas are colored or shaded to reflect the value of the mapped phenomenon or to display classes of values. The word choropleth is derived from Greek: choros (place) and pleth (value). Most people have seen choropleth maps (think of election night and the evening news), but few people know them by this name. Choropleth maps can be especially useful for making comparisons between maps (time series for the same variable or two separate variables) and when viewing data in geospatial relationships (e.g., adjacency or spatial autocorrelation). Briefly, the three main characteristics of choropleth maps are as follows: they are used to display quantitative and qualitative areal variables; observations are classified into classes; and, each class is assigned an areal symbol/color.

Choropleth Map, Unemployment and United States

Screenshots taken from NYTimes Interactive graphic. I liked these maps because we can sere age and unemployment rate in the U.S. and the severity of the unemployment in many of those areas.

In 2008, the unemployment rate was 6.1 %. Between 1976 and 2008, the unemployment rate reached its highest levels in 1983 (12.0%) and 1993 (11.4%), following two major recessions in Canada. In 2007, Canada recorded its lowest unemployment rate (6.0%) since the mid-1970s.

From the mid-1970s to the late 1980s, the unemployment rate for men was usually lower than that for women. However since 1990, this trend has reversed and the unemployment rate for women has been consistently lower than that of their male counterparts. In 2008, the unemployment rate for women was 5.7%, while that for men was 6.6%.

Unemployment generally decreases with age. In 2008, the unemployment rate ranged from 11.6% for youth aged 15 to 24 to 2.8% for individuals 65 years of age and over who were in the Labour force.

Dot Density map of Total Unemployment at ward level

Dot density maps are used to represent precisely what the name implies: density. These maps show the raw population data for each county in Arizona and New Mexico. The dots on a dot density map do not represent the actual locations of these people. Rather, the number of dots within a county is indicative of the number of total people in the county. For instance, a county with 2 dots in it has somewhere on the order of 1400 people in it (since, in these maps, one dot is defined to be equivalent to 700 people). A county with 100 dots in it has somewhere on the order of 7000 people in it, and so on. These maps are useful because they make it very clear where the population is concentrated in these two states.

In February, the number of unemployed persons, at 14.9 million, was essentially unchanged, and the unemployment rate remained at 9.7 percent.

Among the major worker groups, the unemployment rates for adult men (10.0 percent), adult women (8.0 percent), whites (8.8 percent), blacks ...