# Statdisk Notes for Activity 2

## Creating the Worksheet

- Label two columns as
**x** and **y**.
- Enter the x and y values from the target to the center to the washer in each
column

## Calculating the Distances (Question 3)

You need to find the mean **x** and **y** values before completing this step.

- Go to Data / Sample Transformations
- Enter
**SQRT(COL1^2+COL2^2)** in the Advanced Transformation window
- Click on Adv Transform
- Copy the results

- Switch to the sample editor window
- Paste the results into column 3.
- Switch back to the Sample Transformations Window
- Enter
**SQRT((COL1-XBAR)^2+(COL2-YBAR)^2)** in the Advanced Transformation window. Replace the XBAR and YBAR by the values you found for the mean of x and mean of y.
- Click on Adv Transform
- Copy the results

- Switch to the sample editor window
- Past the results into column 4
- Label columns 3 and 4 as d1 and d2 respectively.

## Summarizing the Data (Question 4)

Do this as a check. I want you to find the values asked
for by hand as practice for the test.

Statdisk does not find the variation for you. Another name for Variation is
Sum of Squares, but the Sum of Squares under the Statistics box is the uncorrected
sum of squares, which is what you get if you just square the values and add
them up, not the value we want which is found by subtracting the mean before
squaring the values.

- Choose Data / Descriptive Statistics
- Select column 1
- Click Evaluate
- Repeat steps 1-3 with column 2-4.

You should get some output window similar to what is shown to the right.

Check the sample size, mean, median, variance, and standard deviation with
what you calculated by hand.