Résumé en anglais

The paper presents some preliminaryresults concerning the comparison ofintervals using a continuous evaluationof positive and negative reasons. Moreprecisely we present a valued extensionof the recently introduced conceptof PQI interval order. The main ideais that, while comparing objects representedby intervals of values, thereis a zone of hesitation between strictdifference and strict similarity whichcould be modelled through valued relations.The paper presents suitable definitionsof such valued relations fulfillinga number of interesting properties.The use of such a tool in data analysisand rough sets theory is discussed in thepaper.