Piaget

• year?

  1952
• prediction?

  children in concrete operational stage would demonstrate conservation but children in pre-operational stage wouldn't
• IV?

  age of children used
• DV?

  whether they'd conserve number or not
• measures?

  independent measures - two separate groups of children representing different age groups
• sample?

  small group of Swiss school children including Piaget's own
• method?

  each child shown two identical parallel rows of counters

  asked if there's the same number in each row

  one row was spread out

  child then asked same question
• study found?

  3-4 year olds (pre-operational stage) said more in spread out row when asked the second time

  5-6 year olds (end of pre-operational stage) said both were the same but couldn't justify

  7+ year olds (concrete operational stage) said both were the same and could explain logic - showing they're able to conserve
• criticisms?

  • same question twice - small children could think they're first answer was wrong so changed answer second time
  • sample was culturally biased
  • sample was so small it's hard to generalise
  • experiment used an artificial task that had little bearing on real life
  • lacked construct validity as a narrow measure of conservation had been taken - there are many other ways conservation