Instructions
User has to input the end time of interval where g-renewal process parameters will be calculated, then input the number N of components observed. Each component should have a set of event times ending with integer number 0 or -1. Number 0 indicates that the component suspended at the time corresponding to the previous number. Number -1 corresponds to the case when observation finished at the last event which is the previous number. All N sets of event times should be stored in a text file (with .txt extension). If it is convenient, the user can prepare input data in Excel format and then copy and paste the data in a .txt file and then use it in the calculation.

The following example of input data is the result of observation of 5 components. The observation of first two components finished at their last failure. Corresponding set of numbers (times) is finished with -1. Last 3 components were suspended at time 60.

13.67 21.08 25.26 32.34 -1
1.001 45.96 -1
37.27 60.0 0
5.69 10.69 15.33 25.06 27.79 55.11 60.0 0
2.70 7.95 10.35 25.00 54.91 56.91021 60.0 0

Each number in the file should be separated by white space or new line ("Enter"). Note that two integer numbers without separator will be read as one number, for example "23" and "67" will be read as "2367". Two float numbers without separator could be corrupted, for example "0.34" and "3.5" typed as "0.343.5" can be read as "0.343" and "0.5". We check the format of input numbers and in the most cases one will get an error message if the format is not valid, but it is the responsibility of the user to prepare the input data properly. We also check for consistency of the input set of numbers. One can use "Browse" to select the required file and click "Upload" to submit.

On the next page the user has the Mean repair time, and then Kijima model 1 or 2 and restriction for restoration factor should be selected. Then user should select type of equation for scale parameter. Calculation takes several seconds. If calculation takes more than 1 minute, it is likely that input is not correct, or mission time is too large. Please check your input file and value of mean time to repair entered.

To find maximum likelihood we use modifications of the Newton-Raphson iterative method. Iterations can lead to several local maximum values; therefore, we provide users the option to enter the initial value of restoration factor which is 0.1 by default. By entering several initial values of restoration factor q, user can find global maximum or minimum. In addition, different types of Kijima models and types of equations for scale factor can be selected.

After clicking "Calculate"" you will get the result on the same page. You can change calculation options on this page without uploading the same input file if the session has not timed out.