Explain role of probability? How it is useful in research?
Answers
If The Weather Network informs you that the probability of precipitation is 80 per cent for the day, it might prompt you to carry an umbrella.
We often use probability assessments informally in our daily lives to plan or make decisions. Formal probability theory is a fundamental tool used by researchers, health-care providers, insurance companies, stockbrokers and many others to make decisions in contexts of uncertainty.
Probability provides information about the likelihood that something will happen. Meteorologists, for instance, use weather patterns to predict the probability of rain. In epidemiology, probability theory is used to understand the relationship between exposures and the risk of health effects.
Let’s start with a simple, classic example to illustrate probability: the toss of a coin. You know intuitively that there is a 50 per cent chance of getting heads, and 50 per cent chance of getting tails. If you want to actually do the math to calculate the probability of a head, here’s the basic formula:
Count the number of times that the event will happen – in this case, there’s just one chance of a head appearing, so it’s 1. Divide this by the total number of possible outcomes. With a coin, it’s either heads or tails – which is 2 outcomes. So the probability of getting heads is 1÷2, or 50 per cent.