How to "fuska" with statistics

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How to "fuska" with statistics
For p3 science coffee 2005-12-7 Yama
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Deliminator / null case

• Latitude ???

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Limit of traversal
Don't forget the orbital characteristic
(2) Longitude ???
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Clear cases
Weak/absent
Must take over total including null
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Can we "test" ?

• Fact Magnetic storm Dst Ring current
• Hypothesis Magnetic storm is the cause
• Examine take correlation with Dst

number

Yes !
Dst0 0 -30 -30 -60 lt-60
(4) Check also AE

No !
AE 0 50 100 150 200 300 400 600
Confirm the hypothesis ! gt wrong !!
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We need classification

• up to 1980's Guillain-Barre Syndrome (GBS)
• (yes) medicine-1 (Steroid)
• (yes) medicine-2 (PE)
• (?) medicine-3 (IVIG)

1990 establish CIDP, re-define GBS ? CIDP GBS
(never!) medicine-1 (yes) medicine-2 or
medicine-3 CIDP (yes) all

• 2000 establish AMAN?AIDP
• re-define GBS AMANAIDP
• AMAN
• (never!) medicine-1
• (yes) medicine-2 or medicine-3
• (best) combination of medicine-3 -1
• AIDP (yes) medicine-2 or medicine-3

1. Steroid anti-inflammatory corticosteroids 2.
PE plasma exchange 3. IVIG intravenous immune
globulins
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However,,,,
If we classify in MLT
AE
Dst
Different result !
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Yet,,,
If we limit to 12 MLT, Dst is.
Dst
AE
Correlation with Dst only gt Hypothesis is right
???
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However (2) Total number
8/39 50/154 14/26
Dst gt 0 0 -30 lt -30

• Majority (58/72) is during Dstgt-30
• Hypothesis is wrong !
• correlation is "necessary condition"
• but not "sufficient condition"
• Making ypothesis is misleading !

What causes "majority cases" ?
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First check axis change
Dst
AE
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Second check past history
Dst
AE
hours
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With number
Again, need numbers!
25 6 31 35 12 9 9 9 9 7 8 8 7
7 6 7 5 3 3 151
Dst
57 17 74 92 45 35 30 27 23 13 11 15 15 13 8 13 13
13 5 51
AE
hours
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Without number
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Right statement Out of 202 clear-case
traversals, 179 traversals (89) are within 12
hours after hourly AE gt 300 nT activities,
whereas only 55 traversals (27) are within 12
hours after Dst lt -30 nT activities
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Some note on Distribution
MLT 6 9 12 15 18
double peak
hours
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possibility
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Distirubition

• Most probable duration is 12 hours
• Most probable interval 78 hours
• gt Majority is (c) with 78 hour interval ???

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Distirubition

• Most probable duration is 12 hours
• Most probable interval 78 hours
• gt Majority is (c) with 78 hour interval ???

No ! Only 10 of intervals (3 in hours) are 78
hours