Statistical Analysis

Students in IB biology are expected to have acquired competence in the areas of mathematics set out below in order to develop the knowledge, understanding and skills in the subject content.  All IB biology students should be able to:

• Perform the basic arithmetic functions: addition, subtraction, multiplication and division.
• Recognize basic geometric shapes.
• Carry out simple calculations within a biological context involving means, decimals, fractions, percentages, ratios, approximations, reciprocals and scaling.
• Use standard and scientific notation.
• Recognize direct and inverse proportion.
• Represent and interpret frequency data in the form of bar charts, column graphs, histograms and pie charts.
• Determine the mean, mode and median of a set of data.
• Plot and interpret graphs (with suitable scales and axes) involving two variables which show linear or non-linear relationships.
• Plot and interpret scatter graphs to identify a correlation between two variables, and appreciate that the existence of a correlation does not establish a causal relationship.
• Demonstrate sufficient knowledge of probability to understand how Mendelian ratios arise and to calculate such ratios using a Punnet grid.
• Recognize and use the relationships between length, surface area and volume.

The following statistical analysis methods will be used during the data processing of investigations:

• Mean
• Standard deviation
• Independent T-test
• ANOVA
• Correlation coefficient
• Chi-square Goodness of Fit
• Chi-Square Test for Independence

Not sure which statistics test you should be using for data analysis?  View some helpful flowcharts to help you decide.  Another good resource is the Handbook of Biological Statistics.