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> Alternatively I think instead of displaying a meaningless number we ought
> to go by a percentage (the double spend improbability) and go by
> 'confidence'.


That is a great idea, and not too hard to implement.  A bit of code can
determine over the last N blocks, how many blocks that were at the current
depth of the present transaction were orphaned and divide that by the total
number of blocks solved (orphaned or not) while those N blocks were
solved.  That's the historical number (H), and then the "51% attack" number
(A) can make an explicit assumptions like "Assuming a bad actor has 51% of
the hashing power for 24 hours starting right now, the block holding this
transaction has an X% chance of being orphaned."  Report "# confirmations"
as "99.44% confidence" using [100% - max(H,A)].

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<div dir=3D"ltr"><br><div class=3D"gmail_extra"><div class=3D"gmail_quote">=
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex">
Alternatively I think instead of displaying a meaningless number we ought<b=
r>
to go by a percentage (the double spend improbability) and go by<br>
&#39;confidence&#39;.</blockquote></div><br></div><div class=3D"gmail_extra=
">That is a great idea, and not too hard to implement.=C2=A0 A bit of code =
can determine over the last N blocks, how many blocks that were at the curr=
ent depth of the present transaction were orphaned and divide that by the t=
otal number of blocks solved (orphaned or not) while those N blocks were so=
lved.=C2=A0 That&#39;s the historical number (H), and then the &quot;51% at=
tack&quot; number (A) can make an explicit assumptions like &quot;Assuming =
a bad actor has 51% of the hashing power for 24 hours starting right now, t=
he block holding this transaction has an X% chance of being orphaned.&quot;=
=C2=A0 Report &quot;# confirmations&quot; as &quot;99.44% confidence&quot; =
using [100% - max(H,A)].<br></div></div>

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