HOW TO FIND REGRESSION EQUATIONS WITH TI83 CALCULATOR

Steps |
Key Sequence |
Screens |

1. Enter independent data into list, L_{1} |
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2. Enter dependent data into list, L_{2} |
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3. Set up Stats Plotter for scatter plot AND plot the data | ||

4. Set up the calculation for the regression equation | Press STAT | |

once | ||

4 [for LinReg(ax+b)] |
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NOTE: The other regression equations
(i.e., exponential - ExpReg and quadratic - QuadReg) are determined in the same manner. |
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press 2^{nd} then 1 (for L)_{1} |
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comma | ||

press 2^{nd} then 2 (for L)_{2} |
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5. Calculate the regression equation | ENTER | |

6. Store the equation so it can be graphed | press Y= and scroll to a location which is blank | |

Press VARS | ||

5 (for Statistics...) |
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twice (to EQ) |
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1 (to choose RegEQ) |
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7. Graph | press GRAPH | |

Steps |
Key Sequence |
Screens |

8. Find the details | TRACE and use left and right arrow keys | |

* P1:L1,L2 means this is Plot1 (scatterplot) with x–values (independent variable) in L_{1}
and y–values (dependent variable) in L_{2}* Y=15 gives value of y variable when x variable is 526. |
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TRACE and use up arrow keys to trace line | ||

* Y1 means the regression line is being traced * The point ( X, Y) is on the regression line where X = 541.33191 and Y=26.16118. |
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NOTE: To make predictions on the basis of your regression line, use the TRACE function
and manually type in the appropriate x–value – the y–value will appear on
the bottom right of your screen. If there is an error, then ZOOM Out and try again. |