Table : TABLE 12-5. Calculating the Total Sum of Squares The total sum of squares is calculated by subtracting the overall mean, called the grand mean, from every score to create deviations, then squaring the deviations and summing the squared deviations.

Sample	X	(X − GM)	(X − GM)²
Foraging	28	−11.385	129.618
	36	−3.385	11.458
	38	−1.385	1.918
M_for = 33.250	31	−8.385	70.308
Farming	32	−7.385	54.538
	33	−6.385	40.768
M_farm = 35.000	40	0.615	0.378
Natural resources	47	7.615	57.988
	43	3.615	13.068
M_nr = 47.333	52	12.615	159.138
Industrial	40	0.615	0.378
	47	7.615	57.988
M_ind = 44.000	45	5.615	31.528
	GM = 39.385		SS_total = 629.074