text: require('proof')(5, prove)
  
  function prove (okay) {
      var Assessment = require('..')
      new Assessment().sample(0)
      var time = 1
      var assessment = new Assessment({
          empty: 0,
          intervals: [ 6000 ],
          Date: { now: function () { return time++ } }
      })
      okay(assessment.summarize(),  { '6000': { mean: 0, median: 0, min: 0, max: 0 } }, 'null')
      assessment.sample(1)
      assessment.sample(2)
      assessment.sample(3)
      okay(assessment.summarize(), { '6000': { mean: 2, median: 2, min: 1, max: 3 } }, 'summarize')
      time = 6002
      assessment.sample(4)
      okay(assessment.summarize(), { '6000': { mean: 3, median: 3, min: 2, max: 4 } }, 'shift')
      assessment.sample(1)
      okay(assessment.summarize(), {
          '6000': { mean: 2.6666666666666665, median: 3, min: 1, max: 4 }
      }, 'median add odd')
      time = 12003
      assessment.sample(4)
      assessment.sample(3)
      assessment.sample(2)
      assessment.sample(1)
      okay(assessment.summarize(), {
          '6000': { mean: 2.5, median: 2, min: 1, max: 4 }
      }, 'median remove even')
      time = 18004
      assessment.sample(0)
      assessment.sample(6)
      assessment.sample(5)
      assessment.sample(4)
      assessment.sample(3)
      assessment.sample(2)
      assessment.sample(1)
  }
  