Formula computation (please help!)

[Joker8811]

Hello guys! I need some quick help right now please!
I have to give back a paper for monday, where one of the exercises ask me to compute a series in wich there is the greek symbol "Delta", with a subscript of 12. I don't know how to insert the symbol Delta (as a mathematic function of course) and its subscript.

The complete series is:
g with subscript t = 100*(delta with subscript 12) ln(y with subscript t)

Please could you give me a quick response about it? Maybe also explaining me the meaning of the Delta? Thanks a lot to all of you!!

 

[texasalynn]

welcome to MrExcel board....

try Wingdings 3 font, & type 'r'

 

[Joker8811]

Thanks sincererly for the answer, but i don't think this will help.
I don't need the greek letter "Delta", but the mathematical function that is RAPPRESENTED by Delta (with the subscript included also).
I have to compute that formula i wrote in the first post. Suppose in that formula y=10, could you actually find the relative value of g (using the delta in the formula also of course)? Somebody can help please??!!!

 

[shg]

A little more information from you would help.

There is a Dirac delta function used in integration, the Kronecker delta, and probably some more delta functions. Delta is also commonly used to represent discrete differences in difference equations. Which is yours?

There is no DELTA function in Excel.

In fairness, texaslynn answered the question you asked, which was how to insert the symbol delta.

 

[texasalynn]

<TABLE style="WIDTH: 175pt; BORDER-COLLAPSE: collapse" cellSpacing=0 cellPadding=0 width=233 border=0 x:str><COLGROUP><COL style="WIDTH: 175pt; mso-width-source: userset; mso-width-alt: 8521" width=233><TBODY><TR style="HEIGHT: 21pt" height=28><TD class=xl24 id=td_post_2651992 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 175pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 21pt; BACKGROUND-COLOR: transparent" width=233 height=28>g<SUB>t</SUB>=100*(r<SUB>12</SUB>)In(y<SUB>t</SUB>)</TD></TR></TBODY></TABLE>

 

[Joker8811]

<table style="width: 175pt; border-collapse: collapse;" x:str="" width="233" border="0" cellpadding="0" cellspacing="0"><colgroup><col style="width: 175pt;" width="233"></colgroup><tbody><tr style="height: 21pt;" height="28"><td class="xl24" id="td_post_2651992" style="border: 0.5pt solid windowtext; width: 175pt; height: 21pt; background-color: transparent;" width="233" height="28">g_t=100*(r₁₂)In(y_t)</td></tr></tbody></table>

Seems nice i would try.

Anyway this is the exact text of the paper (hope my teacher will not see this XD) just to make you understand what we are talking about:

"The monthly series on US Retail Sales (Diebold, Chapter 4, 1954:1-1995:1, 493 observations) is contained in the text file rsales.txt. The original series is labelled "rsales" in the file and will be referred to as yt henceforth.

(a) Compute the series gt = 100 * Δ12 ln(yt) and display it graphically."

The text file "rsales.txt" contain just a column of various numbers. That's it. The "12" is the subscript of the Delta, even if it didn't visualize like that. Hope you could understand it better now. Some help for solving it guys? Thanks a lot!!

 

[shg]

We still don't know what Delta is. Maybe your teacher could provide some guidance.

Maybe it means an 12-month offset from the yt data.