{"id":62,"date":"2022-05-18T16:36:12","date_gmt":"2022-05-18T16:36:12","guid":{"rendered":"https:\/\/pressbooks.ccconline.org\/accintrostats\/chapter\/stem-and-leaf-graphs-stemplots-line-graphs-and-bar-graphs\/"},"modified":"2022-11-09T16:36:45","modified_gmt":"2022-11-09T16:36:45","slug":"stem-and-leaf-graphs-stemplots-line-graphs-and-bar-graphs","status":"publish","type":"chapter","link":"https:\/\/pressbooks.ccconline.org\/accintrostats\/chapter\/stem-and-leaf-graphs-stemplots-line-graphs-and-bar-graphs\/","title":{"raw":"Chapter 2.3: Bar Graphs, Histrograms, and Stem-and-Leaf Graphs (Stemplots)","rendered":"Chapter 2.3: Bar Graphs, Histrograms, and Stem-and-Leaf Graphs (Stemplots)"},"content":{"raw":"

Bar Graphs<\/h2>\r\n

Bar graphs<\/strong> consist of bars that are separated from each other. The bars can be rectangles or they can be rectangular boxes (used in three-dimensional plots), and they can be vertical or horizontal. The bar graph<\/strong> shown in (Figure)<\/a> has age groups represented on the x<\/em>-axis<\/strong> and proportions on the y<\/em>-axis<\/strong>.<\/p>\r\n\r\n

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By the end of 2011, Facebook had over 146 million users in the United States. (Figure)<\/a> shows three age groups, the number of users in each age group, and the proportion (%) of users in each age group. Construct a bar graph using this data.<\/p>\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n
Age groups<\/th>\r\nNumber of Facebook users<\/th>\r\nProportion (%) of Facebook users<\/th>\r\n<\/tr>\r\n<\/thead>\r\n
13\u201325<\/td>\r\n65,082,280<\/td>\r\n45%<\/td>\r\n<\/tr>\r\n
26\u201344<\/td>\r\n53,300,200<\/td>\r\n36%<\/td>\r\n<\/tr>\r\n
45\u201364<\/td>\r\n27,885,100<\/td>\r\n19%<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n
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\"This<\/span><\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n
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Try It<\/div>\r\n
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The population in Park City is made up of children, working-age adults, and retirees. (Figure)<\/a> shows the three age groups, the number of people in the town from each age group, and the proportion (%) of people in each age group. Construct a bar graph showing the proportions.<\/p>\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n
Age groups<\/th>\r\nNumber of people<\/th>\r\nProportion of population<\/th>\r\n<\/tr>\r\n<\/thead>\r\n
Children<\/td>\r\n67,059<\/td>\r\n19%<\/td>\r\n<\/tr>\r\n
Working-age adults<\/td>\r\n152,198<\/td>\r\n43%<\/td>\r\n<\/tr>\r\n
Retirees<\/td>\r\n131,662<\/td>\r\n38%<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n
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The columns in (Figure)<\/a> contain: the race or ethnicity of students in U.S. Public Schools for the class of 2011, percentages for the Advanced Placement examine population for that class, and percentages for the overall student population. Create a bar graph with the student race or ethnicity (qualitative data) on the x<\/em>-axis, and the Advanced Placement examinee population percentages on the y<\/em>-axis.<\/p>\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n
Race\/Ethnicity<\/th>\r\nAP Examinee Population<\/th>\r\nOverall Student Population<\/th>\r\n<\/tr>\r\n<\/thead>\r\n
1 = Asian, Asian American or Pacific Islander<\/td>\r\n10.3%<\/td>\r\n5.7%<\/td>\r\n<\/tr>\r\n
2 = Black or African American<\/td>\r\n9.0%<\/td>\r\n14.7%<\/td>\r\n<\/tr>\r\n
3 = Hispanic or Latino<\/td>\r\n17.0%<\/td>\r\n17.6%<\/td>\r\n<\/tr>\r\n
4 = American Indian or Alaska Native<\/td>\r\n0.6%<\/td>\r\n1.1%<\/td>\r\n<\/tr>\r\n
5 = White<\/td>\r\n57.1%<\/td>\r\n59.2%<\/td>\r\n<\/tr>\r\n
6 = Not reported\/other<\/td>\r\n6.0%<\/td>\r\n1.7%<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n
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\"This<\/span><\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n
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Try It<\/div>\r\n
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Park city is broken down into six voting districts. The table shows the percent of the total registered voter population that lives in each district as well as the percent total of the entire population that lives in each district. Construct a bar graph that shows the registered voter population by district.<\/p>\r\n\r\n<\/colgroup>\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n
District<\/th>\r\nRegistered voter population<\/th>\r\nOverall city population<\/th>\r\n<\/tr>\r\n<\/thead>\r\n
1<\/td>\r\n15.5%<\/td>\r\n19.4%<\/td>\r\n<\/tr>\r\n
2<\/td>\r\n12.2%<\/td>\r\n15.6%<\/td>\r\n<\/tr>\r\n
3<\/td>\r\n9.8%<\/td>\r\n9.0%<\/td>\r\n<\/tr>\r\n
4<\/td>\r\n17.4%<\/td>\r\n18.5%<\/td>\r\n<\/tr>\r\n
5<\/td>\r\n22.8%<\/td>\r\n20.7%<\/td>\r\n<\/tr>\r\n
6<\/td>\r\n22.3%<\/td>\r\n16.8%<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n
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Histograms<\/h2>\r\n

For most of the work you do in this book, you will use a histogram to display the data. One advantage of a histogram is that it can readily display large data sets. A rule of thumb is to use a histogram when the data set consists of 100 values or more.<\/p>\r\n

A histogram<\/span> consists of contiguous (adjoining) boxes. It has both a horizontal axis and a vertical axis. The horizontal axis is labeled with what the data represents (for instance, distance from your home to school). The vertical axis is labeled either frequency<\/span> or relative frequency<\/span> (or percent frequency or probability). The graph will have the same shape with either label. The histogram (like the stemplot) can give you the shape of the data, the center, and the spread of the data.<\/p>\r\n

The relative frequency is equal to the frequency for an observed value of the data divided by the total number of data values in the sample. (Remember, frequency is defined as the number of times an answer occurs.) If:<\/p>\r\n\r\n