# Statistical Analysis

**Statistics is no longer a unit in itself as it now finds itself embedded in several units and lab works but it is worth considering in details. Student must make sure that they achieve appropriate level of understanding and can apply these methods (T-test and Chi -squared) in order to fulfill the requirements of both the examination and the internal investigation.**

## Learning targets

#### Nature Of Science

In Biology the variability between replicate samples is often vastly superior to the uncertainties of measurements, and therefore, Biologists relies heavily on statistical analysis. Discuss how uncertainties and varations are handled in Biology, compared to Chemistry and Physics.

- State that error bars are a graphical representation of the variability of data.
- Calculate the mean and standard deviation of a set of values.
- State that the term standard deviation is used to summarize the spread of values around the mean, and that 68% of the values fall within one standard deviation of the mean.
- Explain how the standard deviation is useful for comparing the means and the spread of data between two or more samples.
- Deduce the significance of the difference between two sets of data using calculated values for t and the appropriate tables.
- Explain that the existence of a correlation does not establish that there is a causal relationship between two variables.

## Learning resources

- POWERPOINT - Statistical Analysis
- WORKSHEET - T-test practice sheet
- WORKSHEET - Chi Square