WordRel.com

• a calculation that results in an estimate that is too high

  synonym	overestimationoverratingoverreckoning
  hypernym	approximationestimateestimationidea

• an appraisal that is too high

  synonym	overappraisaloverestimationovervaluation
  hypernym	appraisalestimateestimation

• make too high an estimate of

  synonym	overrate
  also	estimate
  antonym	underestimate
  derivation	overestimationoverestimation
  other	overestimationoverestimation
  hypernym	misjudge
  hyponym	overcapitaliseovercapitalize

• assign too high a value to

  synonym	overvalue
  antonym	underestimate
  derivation	overestimation
  other	overestimation
  hypernym	value