Confidence Intervals

Example: We consider a data set with one factor and several levels, as in the following table.

Factor	Fiber Strenght
15	7
15	7
15	15
15	11
15	9
20	12
20	17
20	12
20	18
20	18
25	14
25	18
25	18
25	19
25	19
30	19
30	25
30	22
30	19
30	23
35	7
35	10
35	11
35	15
35	11

^{click here to download the data}

To use the tool Confidence Intervals, the user must follow these steps:

2. The following screen will be shown:

3. With the cursor in the field Data Set, select the columns that contain the data, including the titles of the columns. If only the data are selected, disable the option Columns with Name. The names of the columns can not contain sumbols, space or tab.

4. Then, click the button Read.

5. Select the Response Variable, in the appropriate item.

6. Create the Formula: use double click in the variables of the process to add it in the box Formula.

7. In Show Results, choose one of the option. We suggest the option New Sheet, because Action does not have the undo command.

8. To finish, click Ok.