To understand the differences between Normal, Binomial, and Poisson distributions, let’s break down their main features:
1. Normal Distribution
- Shape: It looks like a bell and is the same on both sides of the middle point.
- Parameters: It is defined by two things: the average (mean, μ) and how spread out the data is (standard deviation, σ).
- Usage: This distribution is used for continuous data, like measurements. It often comes up when we have a lot of samples.
- Math Formula: The formula for calculating probabilities is a bit complex, but you don’t have to worry about memorizing it right now.
2. Binomial Distribution
- Shape: It can either be balanced or have one side longer, depending on how likely something is to happen (success).
- Parameters: This distribution relies on two things: the number of times we try (n) and the chance of success on each try (p).
- Usage: It's used for data that can be counted, especially when you have a specific number of tries where each try is separate from the others.
- Math Formula: Again, while the math might seem tricky, just know there is a particular way to calculate it.
3. Poisson Distribution
- Shape: This one usually leans to the right at first but can look more balanced when the average (mean rate, λ) is high.
- Parameters: It has just one important number: the average occurrence (λ).
- Usage: It’s great for counting how often things happen in a set time or space.
- Math Formula: Like the others, it has a specific formula to find probabilities.
By knowing these differences, you can choose the right model for different situations where statistics are used.