HCS/438 Statistical Applications
October 12, 2010
“Data are summarized in a visual way using charts and graphs (Rumsey, 2010).” Some of the basic graphs used include pie charts, bar charts, and histograms. Pie charts used more for percentages, bar charts used to compare groups and histograms to show numerical data.
Pie charts take data that is categorized and shows percentages or individuals that can be placed into each category. The sum of all pie slices should equal 100 or 100%. Pie charts are in a circular shape which allows slices of the “pie” to be compared easily. An example of a pie chart would be showing where your money goes when you purchase a lottery ticket. A designated amount for prizes, retailers, and the lottery commission itself, and education.
Bar graphs are used also in summarizing data which has been or can be categorized. The bar graph breaks data into groups showing how many pieces are in one group, or what percentage. Bar graphs are often used to compare groups and breaking the groups down and showing the information side by side. An example of a bar graph would be the number of women in the workforce. Breaking that up into number with children, with children under 10 and children 11-17. Units should be evenly spaced when using a bar graph, beware of the scale used and ensure accuracy when plotting graph points, and if bar graphs represent percent’s be sure to include the total number of individuals or items used to obtain the percent’s Histograms are the graph of choice for numerical data. “Histograms provide a quick look at all the data broken down into numerically ordered groups (Rumsey, 2010)”. A histogram is a bar graph that applies to numerical data. Categories in a histogram are ordered small to large. The bars on the histogram touch each other, they do not overlap. This is to ensure that each number only falls in one group. The...