=+Another analyst worried that different types of cardholders might behave differently. She examined the spending patterns of the cardholders and placed them into five market Segments. When she plotted the data using different colors and symbols for the five different segments, she found the following:

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January 0 1000 2000 3000 4000 5000 6000 7000 December Exercises M16_SHAR8696_03_SE_C16.indd 568 14/07/14 7:37 AM Exercises 569 Look at this plot carefully and discuss why she might be worried about the predictions from the model Jan = +612.07 + 0.403 Dec.