Table 2

Average transaction times for coloured versus plain packs with evidence of a training effect and selection errors

Comparison	Participant numbers	Mean (s)	95% CIs	Mean difference (s)	t Score	p Value
Coloured packs first
Coloured packs 1st 50 transactions	26	3.61	±0.38	0.47	7.783^*	<.001
Plain packs 2nd 50 transactions	26	3.14	±0.28	0.47	7.783^*	<.001
Training effects
Transactions for both packs 1–25	52	3.80	±0.29	0.82	7.539^*	<.001
Transactions for both packs 26–50	52	2.98	±0.17	0.82	7.539^*	<.001
Transactions for both packs 1–50	52	3.39	±0.21	0.46	10.131^*	<.001
Transactions for both packs 51–100	52	2.93	±0.18	0.46	10.131^*	<.001
Controlling for training effects
Coloured packs 1st 50 transactions	26	3.61	±0.38	0.44	2.167^†	0.037
Plain packs 1st 50 transactions	26	3.16	±0.16	0.44	2.167^†	0.037
Coloured packs aggregated	52	3.17	±0.24	0.25	2.103^*	0.040
Plain packs aggregated	52	2.92	±0.14	0.25	2.103^*	0.040
Selection errors
Colour packs	52	0.73 (errors)	±0.31	0.519 (errors)	2.558^‡	0.011
Plain packs	52	0.21 (errors)	±0.14	0.519 (errors)	2.558^‡	0.011