1. CHI-SQUARE
The chi-square test is used to determine whether
there is a significant difference between the
expected frequencies and the observed frequencies
in one or more categories. Do the number of
individuals or objects that fall in each category differ
significantly from the number you would expect? Is
this difference between the expected and observed
due to sampling error, or is it a real difference?
2.
3.
4.
5.
6.
7. No. of
Distance Expected
buses per (O-E) (O-E)2 (O-E)2/E
(km) frequency (E)
min (O)
0 10
1 5
2 3
3 2
Σ
The number of buses observed per minute in relation to
the distance from the city centre.
8. Average
Distance Expected
Diameter of
from source frequency (O-E) (O-E)2 (O-E)2/E
pebbles (mm)
(km) (E)
(O)
0 100
1 60
2 20
3 20
The relationship between the size of pebbles in a river in
relation to the distance from its source. Total
9. Distance Expected
Number of
from house frequency (O-E) (O-E)2 (O-E)2/E
cars seen (O)
(km) (E)
0 52
1 53
2 51
3 44
The number of cars observed in relation to the
distance from my house. Total
