Groups: Overlapping CIs [Design Issues]
Hello Helmut
Yes true. The variability of group 1 is quite high - if we had similar variability than in group 2, then the 90% CIs wouldnt overlap But then again, it makes sense and we all know that with larger sample size and lower variability we get narrower CIs and lesser chance of them overlapping so yes as can be seen it depends on case-by-case basis.
❝ Let’s try a less extreme case with \(\small{\mu_1=0.825,\,\mu_2=1/\mu_1}\):
❝ Simulated data
❝ n = 32
❝ group 1: n = 16, mue = 0.825
❝ group 2: n = 16, mue = 1.2121
❝ Model I (pooled data)
❝ p(G×T) = 0.040949
❝ Model II (pooled data)
❝ PE = 103.96%
❝ 90% CI = 92.58 – 116.73%
❝ CVw = 27.80%
❝ Model III (group 1)
❝ PE = 90.57%
❝ 90% CI = 75.27 – 108.96%
❝ CVw = 30.37%
❝ Model III (group 2)
❝ PE = 119.33%
❝ 90% CI = 104.67 – 136.03%
❝ CVw = 21.28%
❝ \(\small{p(\text{G}\times\text{T})}\) is significant and CIs of groups overlap.
Yes true. The variability of group 1 is quite high - if we had similar variability than in group 2, then the 90% CIs wouldnt overlap But then again, it makes sense and we all know that with larger sample size and lower variability we get narrower CIs and lesser chance of them overlapping so yes as can be seen it depends on case-by-case basis.
Complete thread:
- Possible reasons for group effect GM 2019-07-20 07:36 [Design Issues]
- Group “effect” Helmut 2019-07-20 14:02
- Possible reasons for group effect ElMaestro 2019-07-20 19:20
- Possible reasons for group effect GM 2019-07-23 06:23
- “Group-by-Treatment Interaction” Helmut 2019-07-23 10:32
- “Group-by-Treatment Interaction” BEQool 2024-10-22 12:39
- “Group-by-Treatment Interaction” Helmut 2024-10-22 12:47
- OT: A choice between mittyri 2024-10-22 16:03
- OT: A choice between BEQool 2024-10-23 11:02
- OT: A choice between Helmut 2024-10-23 11:58
- OT: A choice between BEQool 2024-10-23 13:17
- OT: A choice between Helmut 2024-10-23 13:22
- Groups: Overlapping CIs Helmut 2024-11-03 11:36
- Groups: Overlapping CIs BEQool 2024-11-05 09:14
- Groups: Overlapping CIs Helmut 2024-11-05 10:12
- Groups: Overlapping CIsBEQool 2024-11-06 07:44
- Groups: (Hardly‽) overlapping CIs Helmut 2024-11-21 13:20
- Groups: (Hardly‽) overlapping CIs BEQool 2024-11-22 12:32
- Groups: (Hardly‽) overlapping CIs Helmut 2024-11-22 12:58
- Multiplicity? Helmut 2024-11-23 13:05
- Groups BEQool 2024-11-26 08:15
- Groups: (Hardly‽) overlapping CIs BEQool 2024-11-22 12:32
- Groups: (Hardly‽) overlapping CIs Helmut 2024-11-21 13:20
- Groups: Overlapping CIsBEQool 2024-11-06 07:44
- Groups: Overlapping CIs Helmut 2024-11-05 10:12
- Groups: Overlapping CIs BEQool 2024-11-05 09:14
- OT: A choice between BEQool 2024-10-23 13:17
- OT: A choice between Helmut 2024-10-23 11:58
- OT: A choice between BEQool 2024-10-23 11:02
- OT: A choice between mittyri 2024-10-22 16:03
- “Group-by-Treatment Interaction” Helmut 2024-10-22 12:47
- “Group-by-Treatment Interaction” BEQool 2024-10-22 12:39
- “Group-by-Treatment Interaction” Helmut 2019-07-23 10:32
- Possible reasons for group effect GM 2019-07-23 06:23