What is it?
The Statistics and Regression Calculator gives the mean, standard deviation and variance of a list of numbers. If you add a second list (Y values), it also finds the straight line of best fit and shows how closely the two lists are related.
Who is it for?
Students of statistics, researchers, analysts and anyone finding trends in pairs of data.
How to use it
Enter X values, and Y values (optional, for regression) in the same order and the same count. The answer appears as you type; there is no Calculate button. Tap Copy result to copy it, or Share on WhatsApp to send it.
Sample or population?
Use sample variance and standard deviation for measurements from part of a group (most experiments and surveys). Use population when you have every member.
Reading the regression
- Line: y = slope × x + intercept. Use it to predict y for an x inside your data range.
- r from −1 to 1: near 1 is a strong upward line, near −1 strong downward, near 0 no straight-line link.
- r² (r squared) is the share of the variation in y explained by the line.
Cautions
- Correlation isn’t causation: ice-cream sales and drowning both rise in summer.
- Predicting far outside your data is unreliable.
- One extreme point can change the line a lot: check your data for mistakes.
Errors and how to fix them
- “Enter at least two X values”
- “X and Y need the same number of values”: count both lists.
Open the tool: Statistics and Regression Calculator
Still stuck?
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Questions, or an error not listed here?
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