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o Beyond simple counting/tallying, it isalso useful to know the relativefrequency

= The proportion of data valuesthat fall into a particular a class

= C lass frequency / Total y H istograms and Relative- Frequency H istograms

o The interval and ratio data are often presented as either ahistogram or relative-frequency histogram

o D isplays the data from a frequency tableo Each bar represents a classo The width of the bar is the class widtho H owever, the classes do not have to be the same sizeo Shapes of histograms:

y Pie and Bar G raphso Frequency Tables can be easily converted into either a pie

or bar grapho Bar graph:

C an be either vertical or horizontal

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C ustomary to arrange the bars in increasingmagnitude for a vertical bar graph for nominal data

o Pareto C hart A bar graph for which each bar height gives the

frequency of a event A rranged left to right according to decreasing

height It includes a line graph displaying cumulative

percentages

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Exce l

abl e pl ar eto C ar ts

o Pi e Grap s Re q ir es a ition al c al cu la tions in o r e r to

ete r ine a ng les of the p ie w edges

Fi is the fr e q uency of the c a tego r y i o Tim e- Se r ies Grap h

Fo r te m p o ral d a ta sa m pl ed a t r egu lar inte rval s O ften used in fin a nc ial m a tte r s A lwa ys a l ine g rap h