Year 1
Introduction to
Statistics
Name:
Teacher:
1
, Biology’s Problem
Results from biology experiments, unlike physics and chemistry, often don’t give clear cut patterns.
There are several reasons for this:
1.
2.
3.
We can call all these problems ‘chance’ factors.
Our problem is to decide whether any pattern we think we have could just be due to chance factors or whether
it is clear enough for us to see that something significant is going on.
Statistical tests let us do this.
Example
In this case the stats test generates a number ‘r’ which measures how good the correlation is. We are more confident
that this is a significant result if r is high.
If r = 1 then we have a perfect positive correlation, if r = -1 we have a perfect negative correlation, if r = 0 then no
correlation at all.
2
Introduction to
Statistics
Name:
Teacher:
1
, Biology’s Problem
Results from biology experiments, unlike physics and chemistry, often don’t give clear cut patterns.
There are several reasons for this:
1.
2.
3.
We can call all these problems ‘chance’ factors.
Our problem is to decide whether any pattern we think we have could just be due to chance factors or whether
it is clear enough for us to see that something significant is going on.
Statistical tests let us do this.
Example
In this case the stats test generates a number ‘r’ which measures how good the correlation is. We are more confident
that this is a significant result if r is high.
If r = 1 then we have a perfect positive correlation, if r = -1 we have a perfect negative correlation, if r = 0 then no
correlation at all.
2
