#### 1. Bottleneck to learning

Students do not know how exactly to calculate risk. **The risk, in ecology,** is the probability that an event will occur, e.g., that an individual will become ill, injure or die within a stated period or by a certain age. Students get wrong that risk calculation is one of several statistics that have become increasingly important in research (ecological study) and decision-making.

The calculation of the odds ratio is quite simple. It is calculated with the help of a formula. Then, they have to present the formula-produced data in a table format according to strict rules. The main thing that students do wrong is that they present data in a table incorrectly. After that, they get the wrong results in their calculations of risk.

The students are not able to calculate risk correctly because they do not now which parts of the collected data should go into which sections of the given 2 x 2 Table. As a result, their risk calculations are inaccurate.

**CASE STUDY PROVIDED BY ASTA DANILEVIČIŪTĖ, VYTAUTAS MAGNUS UNIVERSITY**