Casio CFX-9970G User Manual page 285

Calculating and Graphing Paired-Variable Statistical Data
6(DRAW)
Gas bills, for example, tend to be higher during the winter when heater use is
more frequent. Periodic data, such as gas usage, is suitable for application of sine
regression.
Example To perform sine regression using the gas usage data shown
below
List 1 (Month Data)
{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39,
40, 41, 42, 43, 44, 45, 46, 47, 48}
List 2 (Gas Usage Meter Reading)
{130, 171, 159, 144, 66, 46, 40, 32, 32, 39, 44, 112, 116, 152, 157,
109, 130, 59, 40, 42, 33, 32, 40, 71, 138, 203, 162, 154, 136, 39,
32, 35, 32, 31, 35, 80, 134, 184, 219, 87, 38, 36, 33, 40, 30, 36, 55,
94}
Input the above data and plot a scatter diagram.
1(GRPH)1(GPH1)
Since this example involves monthly billing, we will assume a period of 12.
• You can also estimate the period by using Trace to manually count the number of
plots between high points or low points of the graph, or you can simply view the
data in the list to see if there is any apparent trend.
Press 6(g)5(Sin) to start sine regression analysis.
6(g)5(Sin)cbcw
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