SVG xy scattergraph template

Volume versus density. Marbles.

SVG xy scatter graph of image depth versus object depth major grid lines axes data points as squares linear regression line text layers Mass versus volume for four marbles Slope is marble density marble volume (cm³) Marble mass (g) y-axis labels 2 7 12 17 22 28 33 38 43 49 54 x-axis labels 1 3 5 7 9 11 13 15 17 19 21

Data table

marble volume (cm³)Marble mass (g)
0.621.65
1.704.35
7.4218.60
21.3153.75
21.3153.75

Carved soap experiment.

SVG xy scatter graph of image depth versus object depth major grid lines axes data points as squares linear regression line text layers Volume versus mass for a bar of soap slope is density Soap volume (cm³) Soap mass (g) y-axis labels 8 9 11 12 13 14 15 17 18 19 20 x-axis labels 8 9 10 11 12 14 15 16 17 18 19

Data table. The variable volumes are due to ± 0.1 mm in actual measures on different slab faces.

Soap volume (cm³)Soap mass (g)
6.98.1
8.08.1
9.08.1
11.312.2
11.712.2
17.420.3
19.020.3

A test of the soap used found that the soap sank in water, as predicted by the density being greater than one.

The initial slab from a half of a bar of GIV soap.

initial soap slab

The initial slab was split roughly 2:1, with all cutting being done by hand. That the result was a strong correlation was both a pleasant surprise and an assurance that the system is relatively robust. The slabs were not perfectly squared off, yet the relation held.

two smaller soap slabs

Typically used functions in conjunction with regressions

Linear Regression Functions
Statistic or ParameterMath symbolStat symbolOpenOffice
Slopemb=SLOPE(y-data;x-data)
Interceptba=INTERCEPT(y-data;x-data)
Correlation r=CORREL(y-data;x-data)
Coefficient of Determination r2 =(CORREL(y-data;x-data))^2
Slope for intercept forced equal to zero=LINEST(y-data;x-data;0)