# Comparison of IQ means of all years

Analysis of the data, and checking the hypotheses

Comparison of IQ means of all years

Hypothesis 1- IQ levels increase from year to year.

Mean IQ:        for year 7 is (104.1+102.4)/2=103.25

for year 9 is (101.4+109.5)/2=105.45

for year 11 is (99.8+101.8)/2=100.8

From the above, we can see that the mean IQ increases from year 7 to year 9, but then goes down in year 11. We can see the same pattern here as in the Pre-survey, where IQs of one or two pupils in year 11 are low, and that makes the mean for the whole group smaller. A bigger sample is required to check whether hypothesis 1 was correct.

Hypothesis 2- IQ levels of pupils doesn’t depend on whether they are left or right-handed.

In year 7 the mean IQ is higher for the left-handed (LH) then for the right-handed (RH). In year 9 it is the other way round. In year 11 the means are about the same for both the LH and RH groups. Hence, hypothesis 2 was correct.

Hypothesis 3- There will be a higher number of children with an IQ lower than the mean for their year group; in all years; however there will be some pupils with a high IQ which will ...