Sharp EL-5230, EL-5250 Statistical Calculation Formulas, σx =, Σx 2 - nx, sx =, Σy 2 - ny, sy =

Chapter 4: Statistical Calculations

Statistical Calculation Formulas

Type	Regression formula
Linear	y = a + bx
Exponential	y = a • ebx
Logarithmic	y = a + b • ln x
Power	y = a • xb
Inverse	1
	y = a + b —
	x
Quadratic	y = a + bx + cx2

In the statistical calculation formulas, an error will occur if:

•The absolute value of an intermediate result or calculation result is equal to or greater than 1 ⋅ 10100.

•The denominator is zero.

•An attempt is made to take the square root of a negative number.

•No solution exists for a quadratic regression calculation.

	Σ x	σx =		Σx2 – nx2	sx =	Σx2 – nx2
x =	n			n		n – 1
Σx = x1 + x2 + ··· + xn			Σx2 = x12 + x22 + ··· + xn2
	Σy	σ y =		Σy2 – ny2	sy =	Σy2 – ny2
y =
				n		n – 1
	n
Σ xy = x1y1 + x2y2 + ··· + xnyn			Σ y = y1 + y2 + ··· + yn		Σ y2 = y12 + y22 + ··· + yn2

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