Unobtrusive Measures

1
Unobtrusive Measures

• The floor tiles around the hatching-chick exhibit
  at Chicagos Museum of Science and Industry must
  be replaced every six weeks. Tiles in other parts
  of the mueseum need not be replaced for years.
• The degree of fear induced by a
  ghost-story-telling session can be measured by
  noting the shrinking diameter of a circle of
  seated children.
• Library withdrawals were used to demonstrate the
  effect of the introduction of television into a
  community. Fiction titles dropped, nonfiction
  titles were unaffected.
• The childs interest in Christmas was
  demonstrated by distortions in the size of Santa
  Claus drawings.
• The introduction of a no alcohol ban in
  fraternities was evaluated by inspecting garbage
  pick-ups for empty bottles.

2

• there is still no person who would not accept
  dog tracks in the mud against the sworn testimony
  of a hundred eye witnesses that no dog had passed
  by.
• Whats obtrusive about obtrusive measures?
• Guinea pig effect
• Role selection
• Measurement as change agent
• Measurement produces lasting change so that
  other measures are effected
• Measurement can change the instrument
• Responses sets
• From Sechrest

3
WAYS TO USE UNOBTRUSIVE MEASURES

• NEEDS ASSESSMENT
• DECIDING TO UNDERTAKE AN EVALUATION
• EVALUATING PROCESS
• PRODUCT EVALUATION

4
Advantages and Disadvantages

• ADVANTAGES
• reduce reactivity
• are honest
• guarantee anonymity
• disguises purpose
• routinizes measurement process

• DISADVANTAGES
• Inability to identify sources of error
• Ability to create measures
• Reliability concerns
• Validity concerns