1. The # of CDs Shipped to Retailers Each Year Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 CDs (millions) 149.7 207.2 286.5 333.3 407.5 495.4 662.1 722.9 778.9 753.1 847.0 938.9 942.5

2. Time Plots Section 9.6

3. Time Plots When analyzing quantitative data, it is common to consider these data as a function of time. To do so, make a scatterplot of the data (y) against time (x), connecting the discrete points with line segments… The resulting line graph is called a time plot.

4. Display the given data in a time plot and analyze any trends in the data. The # of CDs Shipped to Retailers Each Year Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 CDs (millions) 149.7 207.2 286.5 333.3 407.5 495.4 662.1 722.9 778.9 753.1 847.0 938.9 942.5

5. 1988 CDs (millions) Year 2000 100 1000 Explanations for any of the trends???

6. To create this time plot with your calculator: Put the time data into L (let each value be the number of years after 1988) 1 Put the corresponding #s of CDs shipped into L 2 Settings for STAT PLOT1 – Type: Line Graph (it’s a picture!), Xlist: L, Ylist: L 12 Settings for WINDOW: Xmin = –3, Xmax = 15, Xscl = 1, Ymin = 0, Ymax = 1000, Yscl = 1 NOW GRAPH!!!

7. The table below gives the number of cassette units shipped to retailers each year. Compare the cassette trend with the CD trend by overlaying the time plots for the two products. The # of Cassettes Shipped to Retailers Each Year Year 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 Cassettes (millions) 450.1 446.2 442.2 360.1 366.4 339.5 345.4 272.6 225.3 172.6 158.5 123.6 76.0

8. 1988 Units (millions) Year 2000 100 1000 Explanations for any of the trends??? = CD = Cassette

9. The following table lists Proctor’s income for each of the given school years. Create a time plot of the data, and write a brief interpretation of any trends in the data. School Year 00-01 01-02 02-03 03-04 04-05 05-06 06-07 07-08 08-09 Proctor’s Income $26,000 $29,000 $30,000 $31,500 $33,000 $36,500 $300 $5,560 $33,405 Proctor’s Income from All of His Years PMTing

10. 00-01 Proctor’s Income ($ thousands) School Year 08-09 26 Explanations for any of the trends??? 37