Question: Remembering that a running line smooth can be fooled by anomalous data points, use the Minitab macro RLINSMOL with 25% trimming to produce a robust running line smooth, again using k = 15, 25, and 35. Compare the results with the smooths obtained for Problem. Is there evidence of instability, as in the example in Section 10.3.1.1, or does the smooth appear to be well determined?
Problem: Use either the Minitab macro RLINESMO or other software to produce the running line smooth for k = 15, 25, and 35, and compare the results.