| d.4pl | Four parameter logistic desirability function |
| d.central | Central values are desirable |
| d.ends | Extreme (both high and low) values are desirable |
| d.high | High values are desirable |
| d.low | Low values are desirable |
| d.overall | Combine individual desirabilities |
| d.rank | Converts values to ranks, then ranks to desirabilities |
| des.line | Plots a desirability function on an existing graph |
| farmer2005 | Breast cancer microarray dataset |