Among rules of the same salience, newly activated rules are placed using the OPS5 strategy of the same name. First the time tag of the pattern entity associated with the first pattern is used to determine where to place the activation. An activation thats first patternís time tag is greater than another activations first patternís time tag is placed before the other activation on the agenda. If both activations have the same time tag associated with the first pattern, then the LEX strategy is used to determine placement of the activation. Again, as with the CLIPS LEX strategy, negated patterns have pseudo time tags.
As an example, the following six activations have been listed in their MEA ordering (where the comma at the end of the activation indicates the presence of a negated pattern).
rule-2: f-3,f-1 rule-3: f-2,f-1 rule-6: f-1,f-4 rule-5: f-1,f-2,f-3, rule-1: f-1,f-2,f-3 rule-4: f-1,f-2,
Each activation is assigned a random number which is used to determine
its placement among activations of equal salience. This random
number is preserved when the strategy is changed so that the same
ordering is reproduced when the random strategy is selected again
(among activations that were on the agenda when the strategy was
originally changed).