Parameter facts for kids

A parameter is like a special setting or value that helps define how something works or behaves. It's not a number that changes all the time (like a variable), but it's also not a number that always stays the same (like a constant). Think of it as a value you can set, and once it's set, it stays fixed while you observe other things. If you change this setting, the whole system or function might act differently.

In mathematics and statistics, parameters are important values that describe the main features of functions or systems. For example, if you have a formula, some parts might be variables that change often. Other parts are parameters that you set and then keep steady for a while. If you change a parameter, the whole behavior of the function or system changes.

Examples

Let's look at some examples to make it clearer.

Car Speed Example

Imagine you are driving a car.

• The speed of the car is a dependent variable. This means it changes based on something else.
• The position of the gas pedal is an independent variable. This means you control it directly.

Now, think about the car's engine. Engineers can change parts of the engine, like the size of certain levers. If they change these parts, the car's speed will still depend on how much you press the gas pedal. But the car might go much faster or slower for the same pedal position. When the engineers change those engine parts, they are changing a parameter of the car's system.

Bike Income Example

Suppose you want to buy a bike. You believe the money you will earn next month depends on two things:

• The wage you get per hour.
• The number of hours you work.

Let's say your income is y, your wage per hour is a, and the hours you work are x. The formula would be: y = ax (Income = wage x hours)

Now, imagine your boss is very flexible about your hours, so you can work as much or as little as you want. But your boss is very strict about your wage, and you can't change it.

• Your wage (a) is the parameter. It's set for now.
• The number of hours you work (x) is the variable. You can change this easily.

If you and a friend work for the same boss, make the same money, and work the same hours, the formula might change. Maybe your boss gives a bonus, so your income is doubled: y = 2ax (Income = 2 x wage x hours)

• The number 2 is a constant. It never changes.
• Your wage (a) is still the parameter. It's set for a period.
• The number of hours you work (x) is the variable. You can change this.

Graphs in Math

Think about the graph of a relationship like y = ax².

• You usually imagine different values for x (the variable), which makes the curve change along the graph.
• But you usually think of only one value for a (the parameter) at a time.
• If you change the value of a, the shape of the entire curve changes. For example, if a is bigger, the curve might be narrower. If a is smaller, it might be wider.

So, a is a parameter because it's less changeable than x (the variable), but it's not a fixed number like the '2' in x² (which is a constant).

Engineering

In engineering, the word "parameter" is sometimes used to mean an individual item that is measured. For example, a flight data recorder on an airplane might record many different items, and each one might be called a parameter.

The data that one computer program gives to another program is also sometimes called parameters. These are like instructions or specific values that tell the second program what to do.