Graphical Displays of data
The total of all the frequencies in a frequency table is 437. If a section in a pie chart corresponds to an item with a frequency of 182, what is the size of the angle of the corresponding circular wedge? Round your answer to the nearest degree.
150 degrees. Divide F/n*360. 182/437*360 equals 150 degrees
In order to find the percentage of students that are business majors given that the central angle measure is 72 degrees, we need to find the percentage of the circle taken up by the wedge representing business majors. To do this, we need to divide the angle measure by the total number of degrees in a circle.
72/360*100= 20%
determine ratio
Ex: ratio of the number of men to the number of women. Ratio of man in percentage/ ratio of woman in percentage
Bar graphs
X axis display categories; Y axis the frequency / relative frequency
Side by side Charts
bar graph that compares the same categories for different groups
Pareto charts
descending order bars (largest to smallest);Use typically for NOMINAL DATA. If done for an ordinal data, the data will seem out of order
stacked bar graph
display how many subjects from each sample
central angle measures
f/n *360
Pie Charts
qualitative data; It shows how large is each category in relation to the whole. Nominal data; when data is part of a whole ex: budget.A pie chart has to represent all parts of a whole. Determine if the sum of the percents given represent all parts of the total budget.
to calculate the size of each wedge in the pie chart to the nearest whole degree
solve for the relative frequency and look for percentage
Bar graphs
Qualitative data; to see small differences in the amounts of data; is good to use this type of graph when the amounts of data in two or more categories are close to being equal.