Statistical Methods for Psychology

452 Chapter 13 Factorial Analysis of Variance

5

Class 1 Class 2

Variable B

Day Night

Dirt Class 1 Class 2

Variable B

Dirt

10

15

Mean Number Corrections

20

25

30

35

40

5

10

15

Mean Number Corrections

20

25

30

35

40

A 1

(Inexperienced)

A 1

(Inexperienced)

A 2

(Experienced)

A 2

(Experienced)

Figure 13.5 ABCinteraction for data in Table 13.14

Table 13.16 Simple interaction effects for data in Table 13.16

(a) Data and Computations forSSABatC

1

C 1 Means

B 1 B 2 B 3 Mean

A 1 10.00 18.00 20.00 16.000

A 2 7.50 7.00 15.00 9.833

8.75 12.50 17.50 12.917

(b) Data and Computations for SSABatC

2

C 2 Means

B 1 B 2 B 3 Mean

A 1 20.00 27.00 40.00 29.000

A 2 10.00 15.50 17.50 14.333

Mean 15.00 21.25 28.75 21.667

=612.83 2 228.17 2 308.33=76.33

SSAB at C 1 =SSCells AB at C 12 SSA at C 12 SSB at C 1

= 43 [(10.000 2 12.917)^2 1 Á 1 (15.000 2 17.500)^2 ]=612.83

SSCells AB at C 1 =na(Xij 12 X..1)^2

= 43 2[(8.750 2 12.917)^2 1 Á 1 (17.500 2 12.917)^2 ]=308.33

SSB at C 1 =naa(X.j 12 X..1)^2

= 43 3[(16.000 2 12.917)^21 (9.833 2 12.917)^2 ]=228.17

SSA at C 1 =nba(Xi.1 2 X..1)^2

(continues)