Analytics Magazine Analytics Magazine, July/August 2014 | Page 79

Figure 8: NCSS’ output. I chose the “Logistic(4)” from NCSS’ list of “Growth and Other Models.” that you manually enter values for the three smoothing constants. Minitab also has, under the Time Series choice on the main menu, a Trend Analysis option. Choosing that gives the user four possible curves (linear, quadratic, exponential and Pearl-Reed logistic). Figure 9 gives the results of my choice for the “Non-Stop” data, the Pearl-Reed curve (Minitab calls it the S-Curve Trend Model). A NA L Y T I C S Figure 9: Minitab’s output for the Pearl-Reed logistic growth model for the Non-Stop data. J U LY / A U G U S T 2 014 | 79