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

65

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Sharp EL-5230, EL-5250 operation manual Statistical Calculation Formulas, Σy 2 ny Sy =

EL-5230, EL-5250 specifications

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