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Expected value and risk
Calculate expectation and variance of a discrete probability distribution.
Enter outcomes and their corresponding probabilities in matching order. The tool calculates the probability-weighted mean, then the weighted squared deviations and their square root.
How to use
- Enter your text, values, or image.
- Adjust the options and run the tool.
- Copy or download your result.
Worked example
Example input
Outcomes: 0,10 Probabilities (sum to 1): 0.5,0.5
Example result
{
"expectedValue": 5,
"variance": 25,
"standardDeviation": 5
}Limitations and details
Probabilities must lie in [0,1] and sum to one within 10⁻¹⁰; outputs describe the supplied distribution rather than guaranteed outcomes.
Inputs and options
- Outcomes
- Text
- Probabilities (sum to 1)
- Text
Frequently asked questions
Is this tool free and private?
Yes. All 300 tools are free in this phase. Processing happens in your browser; your input and files are not sent to our servers.