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ch9

L

lalala

Member
hi there,
I have 3 quesitons:

the first one is to do with solution 9.17 part 3 on page 43, the 3rd line of equations:
how do you get from exp{-e^(0.01)x(some integral)} to
(exp{-(some integral)}^(e^(0.01))??
is there some algebra rule here I'm missing?

which leads me to my second question:
does "exp()" just mean something to the power of, or is it like "e"?
and if it's to the power of, then how do you interpret
S(t)=exp{something}? is it 1 to the power of {something}?

my last question is form chapter 12, the example on page 35.
how do they calculate the expected values? my stats days are a few years gone by so I cant seem to work it out. I tried to use the question which deals with graduation B(Question 12.10), because there is one interval with only one value{-3,-2}, so I thought it would be easier to follow but I'm not able to get it.

Can you help?
Thanks a million.
 
Provided I've interpreted your questions correctly(with the brackets etc), here goes

1:x^(a*b) = (x^a)^b, eg 2^6 = 2^(3*2) = 8^2

2: exp(x) generally means e^x. (The only reason I can think of for the two forms to be shown in the same equation is formatting when trying to "write" maths in text, eg to save exponentials of exponentials from running on multiple lines)

3: I would need more information, ie the whole question.
 
hi thanks for that.

to expand on the third question:

it asks to analyse the distribution of the standardised deviations for graduation B.
so for the interval(-3,-2), the actual number is 1, and the expected is 0.4.
so I wonder how the expected is calculated?
the data given is as follows:
x = 34
E (to the base) x = 61779
d (to the base) x = 23 = Actual
q hat x = 0.000372
q circle x = 0.0006
E to the base (x) times q circle(x) = 37.07 = E
(A-E)/E = 5.34
E to the base (x) times q circle(x)(1 - q circle x) = 37.05
z = -2.31

sorry about the notation.

i cant seem to figure out how he gets E to be 0.4

thanks again for the help.
 
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