**Using the Linear Regression T Test:** **LinRegTTest**

**Step 1**. In the STAT list editor, enter the X data in list L1 and the Y data in list L2, paired so that the corresponding (x,y) values are next to each other in the lists. (If a
particular pair of values is repeated, enter it as many times as it appears in the data.)

**Step 2**. On the STAT TESTS menu, scroll down with the cursor to select the LinRegTTest. (Be careful to select LinRegTTest as some calculators may also have a different item
called LinRegTInt.)

**Step 3.** On the LinRegTTest input screen enter: Xlist: L1 ; Ylist: L2 ; Freq: 1

**Step 4.** On the next line, at the prompt *β* or *ρ*, highlight " 0" and press ENTER

**Step 5.** Leave the line for "RegEq:" blank Step 6. Highlight Calculate and press ENTER.

The output screen contains a lot of information. For now we will focus on a few items from the output, and will return later to the other items.

The second line says y = a + b*x*. Scroll down to find the values a = -173.513, and b = 4.8273 ; the equation of

the best fit line is

The two items at the bottom are *r ^{2}* = .43969 and

*r*=.663. For now, just note where to find these values; we will discuss them in the next two sections.

**Graphing the Scatterplot and Regression Line**

**Step 1.** We are assuming your X data is already entered in list L1 and your Y data is in list L2

**Step 2**. Press 2nd STATPLOT ENTER to use Plot 1

**Step 3**. On the input screen for PLOT 1, highlight **On** and press ENTER

**Step 4**. For TYPE: highlight the very first icon which is the scatterplot and press ENTER

**Step 5**. Indicate Xlist: L1 and Ylist: L2

**Step 6**. For Mark: it does not matter which symbol you highlight.

**Step 7.** Press the ZOOM key and then the number 9 (for menu item "ZoomStat") ; the calculator will ft the window to the data

**Step 8**. To graph the best ft line, press the "Y " key and type the equation -173.5+4.83X into equation Y1. (The X key is immediately left of the STAT key). Press ZOOM 9 again
to graph it.

**Step 9**. Optional: If you want to change the viewing window, press the WINDOW key. Enter your desired window using Xmin, Xmax, Ymin, Ymax

**With contributions from Roberta Bloom

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