At a much more basic level, you can introduce the notion of interval
estimates by asking the following questions with reference to any concrete
situation:
1a. What does 'true value' mean?
1b. What would you estimate its value is? (point estimate)
2a. What is the largest value you think it could be? Call this the "upper
limit".
2b. ditto, "lower limit"
3. What is the chance that the true value is actually above the upper limit
you have stated? (Respond either verbally - high/medium/low/very low, or by
saying "less than 5%", "10-20%" etc.)
4. Then introduce the standard probability levels (5%,1%) and the 'correct'
terminology.
However, it is important not to go too quickly to the (counter-intuitive)
mathematical - first develop articulacy in thinking and speaking about the
relationships between
true value - estimate of true value - upper and lower limits - probability
of falling within/outside these limits.
JOHN BIBBY
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