Sampling

Question 1

Quadrant?

Answer 1

Counting- simplest method and easy to carry out if the population is small, individuals are easy to identify
Can work out the density

Question 2

Frequency?

Answer 2

Likelihood of counting a particular species in a quadrat

Question 3

Percentage cover?

Answer 3

Appropriate for organisms which form continuous cover over a surface
E.g. lichens and grass
Can be subjective and result in data which isn’t repeatable or comparable to other studies

Question 4

What is the p value?

Answer 4

Probability that differences between results/the pattern occurs purely by chance

Question 5

T test?

Answer 5

Used when we have 2 sets of numerical data which measures the same variable but in 2 distinct populations e.g. population size in 2 areas or lengths of individuals in 2 species

Question 6

What can t tests be used for?

Answer 6

Can be used to determine if the means of 2 sets of data are significantly different from eachother
Must be enough data to calculate a reliable mean

Question 7

What is the null hypothesis?

Answer 7

The hypothesis is incorrect e.g. there is no significant difference between x and y

Question 8

Degrees of freedom?

Answer 8

5% significance level- 95% confident results- the difference is not down to chance
If t > critical value, we can reject the null hypothesis