Launch the Fatigue Model Platform
Launch the Fatigue Model platform by selecting Analyze > Reliability and Survival > Fatigue Model.
Figure 6.4 The Fatigue Model Launch Window
For more information about the options in the Select Columns red triangle menu, see “Column Filter Menu” in Using JMP.
The Fatigue Model launch window contains the following options:
N, Life or Cycles
Identifies the column that contains the lifetime variable (N). When your response values are interval-censored, you can enter two columns. See Specify Two Y Columns.
S, Strain or Stress
Identifies the column that contains the strain or stress variable (S).
Censor
Identifies a column that designates if a response measurement is censored.
Freq
Identifies a column that contains a frequency for each row.
By
Identifies a variable to produce an analysis for each level of the By variable.
Censor Code
Specifies the value in the Censor column that designates censored observations. After a Censor column is selected, JMP attempts to automatically detect the censor code and display it in the box. To change this, click the red triangle and select from a list of values. You can also enter a different value in the box. If the Censor column contains a Value Labels column property, the value labels appear in the list of values. Missing values are excluded from the analysis.
Specify Two Y Columns
In the Fatigue Model platform, you can specify two Y columns when some of the measurements are interval censored or left censored. For a given row, the values in the two Y columns determine the type of censoring.
• If the two Y values are equal and neither is missing, then the common measurement is treated as exact.
• If the two Y values are not equal and neither is missing, then the measurement is interval censored and assumed to be between the two values.
• If only the first value is missing, then the measurement is left censored and assumed to be smaller than the second value.
• If only the second value is missing, then the measurement is right censored and assumed to be larger than the first value.
Note: The only way to fit left-censored measurements in the Fatigue Model platform is with two Y columns.