effectiveness vs effect

[keannu]

What is the difference between effectiveness vs effect? I think "effectiveness" only refers to something's benefit, but effect can mean either benefit or influence or something. "Effect" is wider than "effectiveness", Isn't it?

ex)If the other person is in a rage or a panic, you need to be calm enough for both of you. Your calmness can be as infectious as their anger or fear. Take a deep breath or two until you calm down. The effectiveness of this simple technique of breathing consciously reflects a psychological reality.....

[SoothingDave]

The "effectiveness" is how well something does the job it is intended to do. The effectiveness of a pain medicine or of a gov't program to "stimulate" the economy is a measure of how well it actually works.

An "effect" is simply when one thing influences another.