Value Ordering for Finding All Solutions: Interactions with Adaptive Variable Ordering

Abstract

Abstract. We consider the impact of value ordering heuristics on the search effort required to find all solutions, or proving none exist, to a constraint satisfaction problem in k-way branching search. We show that when the variable ordering heuristic is adaptive, the order in which the values are assigned to variables can make a significant difference in all measures of search effort. We study in depth an open issue regarding the relative merit of traditional value heuristics, and their complements, when searching for all solutions. We also introduce a lazy version of k-way branching and study the effect of value orderings on finding all solutions when it is used. This paper motivates a new and fruitful line of research in the study of value ordering heuristics for proving unsatisfiability.

Role Of MPV And Platelet/MPV Ratio İn The Diagnosis Of Cardiac Dilemma; Cardiac Or Non-Cardiac Chest Pain, And Severity Of Acute Coronary Syndrome

“…Cardiac pathology was determined in 28 patients (5.91%) on readmission on one-month follow-ups of the patients who were recorded to have a non-cardiac pathology on the first admission. On the first admission, the mean MPV values were determined as 7.54 95% CI (7,76), and the mean platelet values were determined as 230060 95% CI (210000-285000). When the patient group that was determined to have cardiac pathology on re-admission was compared with the (MACE -) patient group, the MPV level was statistically significantly higher (p=0.039).…”

“…ACS is among the first leading fatal causes of chest pain and it should be promptly and accurately managed by the clinicians. Troponin is used as a cardiac marker when electrocardiogram (ECG) is not diagnostic however, easy and fast cost-effective additional laboratory tests are required as this laboratory test takes a long time, has a low diagnostic value within the first 12 hours, and yields negative results in 14-20% of the patients (7). Apart from the cardiac markers, the platelet count and MPV measurement are the most studied parameters for the clinical diagnosis.…”

Constraint Reasoning

“…On inconsistent subproblems, the order in which we select values in a domain has little effect because we must try them all. Recently, Mehta et al [2011] have shown that value ordering could have an effect when using an adaptive variable ordering heuristic. As adaptive variable ordering heuristics are affected by past operations of the search procedure, selecting a value instead of another can have an effect on the next choice of variable.…”