Scientific Investigations 4 Example To show accuracy and precision
Imagine a hurling player practising putting frees over the bar. If the player shoots with accuracy, his aim will always put the sliotar between the posts. If the player shoots with precision, his aim will always take the sliotar to the same location which may or may not be between the posts. A good player will be both accurate and precise by shooting the sliotar the same way each time and each time putting it between the posts. If you hit the upright every time, you are precise but not accurate!
Fig. 3 Sports players aim to be both accurate and precise.
Ethics Ethics deals with moral principles. To work in an ethical way scientists have to consider if their actions are morally right or wrong. For example it is possible to design an experiment to see if drinking 20 cans of an energy drink within three hours would affect a person’s health. However, if the scientist is already aware that energy drinks could have serious effects on a person’s health, then the experiment may be considered to be unethical. The question of ethics is complex. For example, some scientists argue that testing on animals is important because it allows us to see the effects of various medicines and cosmetics on a living animal before testing them on humans. Other scientists argue that it is not ethical to intentionally cause harm to an animal for the sake of research. Many countries and scientific organisations have ethics committees to advise on whether a particular investigation is ethical.
4.2 Evaluating investigations
Scientists need to reflect on their results and evaluate them. The following are examples of questions that scientists can use to evaluate an investigation: Are the results accurate? Are the results precise? Is the investigation reliable? Do the results indicate a pattern? Can the scientist repeat the experiment and get the same results? Are one or two of the results different from a general pattern? What could be the reason for that?
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Scientists often set up an investigation expecting to find one outcome but unexpected results must also be analysed. It is important for scientists to reflect on their method – What went right? What went wrong? What could be improved? Investigations are usually repeated to see if the same results are obtained and further investigations may be designed to gather more information.
