Just to recap, Jeanie.
I'd say some humility is called for, but its hard with male pride. And I suspect stubborness. I believe he is basing things on believing you have been the deceiver.
That would just be another in a long line of misunderstandings or misrepresentations.
I predicted that he would not admit to being wrong, and so far I've been correct. His latest attempt involve some "slight-of-hand" falsehoods, ones that are clearly false because we are dealing with math.
In
this post he is trying to pretend that this formula (from his first link, and the one used in the on-line calculator he linked to):
CTD's wikipedia linkA = P(1 + (r/n)}^{nt}
Where,
* P = principal amount (initial investment)
* r = annual nominal interest rate (as a decimal)
* n = number of times the interest is compounded per year
* t = number of years
* A = amount after time t
Is the same as the decay formula:
Nt = No*e^(-?t)
Where Nt = The amount of material at a particular time
No = The initial amount of material.
t = The time expended
? = the decay rate, which is differs between materials
Now we can put the decay formula in terms of the symbols used in CTD's substituted formula:
A = P*e^(rt)
As anyone can see, these are different formulas. You've done math, Jeanie: would you say this is an honest substitution?
It is also easy to show that CTD's chosen formula produces false results by using his on-line calculator:
principal: $100,000.00
nominal interest rate: 10%
compounding period: annual
years: 1
total amount: $110,000.00
annual percentage rate (APR): 10%
So far so good eh?
Now change the compound period to monthly:
principal: $100,000.00
nominal interest rate: 10%
compounding period: monthly
years: 1
total amount: $110,471.31
annual percentage rate (APR): 10.471307%
Notice that the actual annual interest rate (the APR) has changed.
We can do this again with daily periods:
principal: $100,000.00
nominal interest rate: 10%
compounding period: monthly
years: 1
total amount: $110,515.58
annual percentage rate (APR): 10.515578%
And the actual annual interest rate has changed again!
Obviously this does not model something with one fixed rate (like the decay formula uses). This would be like changing ? every time you made a calculation: of course you would get different results because you use a different formula.
Instead of simply admitting that he made a mistake, that he was wrong to calculate his "quarter-life" the way he did, he tries to substitute a different formula.
When that doesn't work, he tries again to distract the thread from the FACT that he was wrong by trying another "
bait and switch" tactic:
Tell me, how did you manage to find the "B" without first reading the "A"? Or did the "A" soar over your head?
Curiously, the "A" doesn't help him either:
The 8% is a nominal rate. It implies an effective quarterly interest rate of 8%/4 = 2%. Start with $100. At the end of one year it will have accumulated to:
$100 (1+ .02) (1+ .02) (1+ .02) (1+ .02) = $108.24
We know that $100 invested at 8.24% will give you $108.24 at year end.
The actual annual rate is 8.24%, and this just shows that the result of using the actual annual rate gives you the same result if you compound quarterly or annually.
Of course, when that distraction doesn't work, then CTD tries another: going to a different topic (where he is also wrong).
Any guesses what the next avoidance move will be?
Enjoy.
