Question

Research Scenario: Does distraction and/or amount of details affect the ability of people to make good decisions? In this fictitious scenario, researchers used a mixed design. Thirty participants were split into two groups – No Distraction or Distraction (n=15 per group). All participants were given TWO scenarios based on amount of details (4 or 12), and were asked to make an objective decision at the end of each scenario. Objective decision was the dependent variable and was quantified numerically using an interval scale of measurement.

Assume the data is parametric. Select and conduct the most appropriate statistical test to determine whether distraction and/or amount of details affect people’s ability to make good decisions.

No Distraction			Distraction
4 details	12 details		4 details	12 details
5.5	0.8		2.5	4.7
5.2	1.2		2.1	5.8
5.3	1.5		2.3	5.3
4.7	1.2		2.4	4.9
4.9	1.3		2.7	4.8
4.8	1.1		2.9	5.7
5.1	0.5		3	5.5
5.2	0.3		2	5.1
5.4	1		2.1	5.3
5.7	0.7		2.4	5.1
5.3	1.4		1.7	5.6
5.1	1.1		2.5	5
5.9	0.9		2.7	4.3
6	1.3		2.3	4.8
5.7	1.2		2.1	4.9

Answer 1

Result:

Research Scenario: Does distraction and/or amount of details affect the ability of people to make good decisions? In this fictitious scenario, researchers used a mixed design. Thirty participants were split into two groups – No Distraction or Distraction (n=15 per group). All participants were given TWO scenarios based on amount of details (4 or 12), and were asked to make an objective decision at the end of each scenario. Objective decision was the dependent variable and was quantified numerically using an interval scale of measurement.

Assume the data is parametric. Select and conduct the most appropriate statistical test to determine whether distraction and/or amount of details affect people’s ability to make good decisions.

Let level of significance = 0.05.

Excel used for calculations:Excel Addon PHStat used

Two-Way ANOVA with replication
SUMMARY	4 details	12 details	Total
No Distraction
Count	15	15	30
Sum	79.8	15.5	95.3
Average	5.32	1.033333333	3.176666667
Variance	0.1489	0.1138	4.8791
Distraction
Count	15	15	30
Sum	35.7	76.8	112.5
Average	2.38	5.12	3.75
Variance	0.1246	0.1717	2.0847
Total
Count	30	30
Sum	115.5	92.3
Average	3.85	3.076666667
Variance	2.3674	4.4570
ANOVA
Source of Variation	SS	df	MS	F	P-value	F crit
Sample	4.9307	1	4.9307	35.2851	0.0000	4.0130
Columns	8.9707	1	8.9707	64.1963	0.0000	4.0130
Interaction	185.1527	1	185.1527	1324.9978	0.0000	4.0130
Within	7.8253	56	0.1397
Total	206.8793	59
			Level of significance			0.05

To test the distraction affect people’s ability to make good decisions, Calculated F= 35.2851, P=0.0000 which is < level of significance 0.05 level. Ho is rejected. We conclude that distraction affect people’s ability to make good decisions.

To test the amount of details affect people’s ability to make good decisions, Calculated F= 64.1963, P=0.0000 which is < level of significance 0.05 level. Ho is rejected. We conclude that amount of details affect people’s ability to make good decisions.

To test the interaction between distraction and amount of details , Calculated F= 1324.9978, P=0.0000 which is < level of significance 0.05 level. Ho is rejected. We conclude that interaction is significant.