Here are two versions.

The first is one interpreted from the Traders Tips Amibroker version of
the indicator.

The second is the sidebar version which may be available for online download from the magazine's site. The magazine is somewhat notorious for being slow to make it available.

You should note that if you compare the 14 [censored]I to a 7 RSI you will see little difference.

Preston

{[censored]I}
{Asymetrical RSI formula}
{TASC OCT 2008 Vervoort}
{Amibroker Version 1.coded for Metastock}
{constant period version (looks into the future)}
Period:= Input("[censored]I Period",1,100,14);
Chg:=C-Ref(C,-1);
UpCount:=Sum(Chg >= 0,Period);
DnCount:=Period - UpCount;
UpMove:=Mov(Max(Chg,0),LastValue(UpCount)*2-1,E);
DnMove:=Mov(Max(-Chg,0),LastValue(DnCount)*2-1,E);
RS:=UpMove/DnMove;
[censored]I:=100-(100/(1+RS));
[censored]I;

{RSI Asymetrical}
{TASC OCT 2008 Vervoort}
{[censored]I Metastock formula}
{requires Equis Forum DLL available at }
{Eguis Metastock Yahoo Group or the Equis Forum}
Period:= Input("[censored]I Time Period ",1,100,14);
UpCount:=Sum(If(ROC(C,1,$) >= 0,1,0),Period);
DnCount:=Period - UpCount;
UpMove:=ExtFml("Forum.MOV",If(ROC(C,1,$)>=0,ROC(C,1,$),0),UpCount*2-1,e);
DnMove:=ExtFml("Forum.MOV",If(ROC(C,1,$)<0,Abs(ROC(C,1,$)),0),DnCount*2-1,e);
RS:=UpMove/(DnMove + 0.0001);
100-(100/(1+RS));