Can you help me better understand the following issue?
US life expectancy - 78.2
UK life expectancy79.4
Source -United Nations World Population Prospects: 2006 revision
What is the statistical significance of a difference of 1.2 years?
would the difference of the size of the respective populations (roughly 300 million verses 60 million) be a relevant factor in how significant this difference is?
is there a better way to phrase this question? Is it the right question?
Thank you in advance for your help.
Best regards,
Randy
Answer randy -
there may be no statistical issues involved here. it all depends on how
the life expectancy numbers were obtained.
if they came from census figures - a complete enumeration of the population -
then no sampling (i.e. randomness) was involved - and the concept of statistical
significance does not apply.
if they were obtained by some sort of random sampling procedure, then one might
speak of the statistical significance of the difference (1.2) between the two
numbers. but it cannot be calculated without all of the original sample data.
the statistical significance would be the chance of getting an observed difference
between the two random sample averages that is at least as large as the observed 1.2
years - IF both populations actually had the SAME average life expectancy.
