A DJ Theory: Mathematically Proven! (now with calculator)

HuuBinh

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A DJ Theory: Mathematically Proven!

I will mathematically prove that when a girl reduces her time being with a guy, the guy's interest level increases.

Let say that the guy's interest level in the girl has a function:

IL = lnD

Where IL = interest level, a function of D, which is the number dating activities. This natural log function is concave which exibits diminishing marginal return of interest.

and he also derives happiness from other nondating activities:

O = lnN

Where O is other activities like sports, parties etc..., this function is also concave.

When we add these two types of utility (happinesss) together (dating & nondating) we have a utility function of:

U = lnD + lnN

This guy also faces a time constraint, which is also a function of dating & nondating activities (D&N), we have the function:

T = Dt + Nt

Where T = total amount of time devoted to dating and nondating.

For example: if he goes on 3 dates per week, each requires about 4 hours, then his dating time alone = 12hrs, excluding his nondating activities.

Individuals maximize their happiness subject to their constraints.

There, if we maximize U, and subject it to the time contraint T, to find the maximum number of dating activies and nondating activies, then we have:

MAX(D, N) s.t. (subject to) T

MAX(D,N) = lnD + lnN - (Dt + Nt - T)

then, i take the partial derivative with respect to D, and N.

dMAX/dD = 1/D - t = 0 ---> t = 1/D
dMAX/dN = 1/N - t = 0 ---> t = 1/N

divide: t/t = (1/D) / (1/N) ---> 1 = N/D

solve for D & N: we have a simple solution: D = N

The time constraint once again is: T = Dt + Nt,

I subsititute D in to this equation to solve for N, and the same for N to solve for D, to have:

N = T / (2t), this small t is the amount of time devoted to nondating activities and,

D = T / (2t), this small t is the amount of time devoted to dating activies;

Once again the utility function:

U = lnD + lnN,

Remember that, his romantic interest derives from dating alone which is the first part of the equation, lnD.

I then, substitute D & N into the ultiltiy function to have:

U = ln [ T / (2t) ] + ln [ T / (2t) ]

O.K. if the girl decides to reduce her time being with this guy, that means, the small t that indicates the amount of time he spends toward dating, must fall. If I isolate the interest level effect of this guy, i have:

IL = lnD

IL = ln [ T / (2t) ], if this (t) falls as a result of less time being with the girl, then according to the equation IL must RISE.

That means, he now has to shift some of his dating time toward his nondating activities. Lets use a numeric example.

In a given week, he has 20hrs to allocate between dating and nondating activities: T = 20

He goes on 2 dates per week each requires 5hrs, and 2 nondating activities each also requires 5hrs.

T = Dt + Nt ---> 2(5) + 2(5) = 20

Substitute these numbers into ultility equation, i have a total utility of:

U = lnD + lnN ---> ln [20 / (2*5) + ln [ 20 / (2*5) = 1.39 utils

*IL = lnD ---> 0.693
O = lnN ---> 0.693

Lets say now the girl still goes out with him 2 dates per week, but this time only 4 hours each instead of 5, thus dating time = 8 hrs.

Thus, he must now allocate that 2hrs extra toward his nondating activies.

Lets say that he still enjoys 2 nondating activities per week, but this time, 6hrs each.

We plug back into the equation to have.

T = Dt + Nt ---> 2(4) + 2(6) = 20hrs <--- still 20hrs per week

U = lnD + lnN ---> ln [20 / (2*4) + ln [ 20 / (2*6) = 1.43

If I isolate the the romantic interest effect alone, then:

IL = lnD ---> 0.916, this is higher than 0.693

This means, less time = more interest.

This result can also be generalized for guys, so SCARCE your time guys.

Comments are welcome!
 

Giovanni Casanova

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Oh f*ck me.
 

Eternal

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Hmm...Less time increases interest level? Wow, this is new!

To be honest...I don't know whether to laugh, cry, move it, close it, or just act like I never saw this...
 

Giovanni Casanova

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Originally posted by crazykid
To be honest...I don't know whether to laugh, cry, move it, close it, or just act like I never saw this...
Loud sobbing followed by repeatedly bashing my head against a door frame worked okay for me.

Just FYI.
 

RedKnight04

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Okay, You lost me once you started to type.
 

rgeere

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Her: It's like we never go out!
Him: (Pulls out calculator)
Her: What are you doing?
Him:Where's the darn function key I need?
Her:What?
Him:The function I need to do some math.
Her: Don't you have any time for someone special?
Him:I'm trying to figure that out!

Lol, I'll be sure to memorize this.

This is good actually, I can use it to see if I am spending to much time with one perticular girl.
 

Cheiradawg

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AHHHH com'on guys!!!

It is guys like this that make your standard of living go up!!!

Appreciate this for what it is. It is just a clevar modeling of a specific situtation. Of course it is not gonna make a damn diffrence in the real world it was just this guys musings. (Hopefully atleast)

Anyway I think it is clevar.

HuuBinh,

This was fun to read. You assumed and generalized a $hit load (but I won't go into that) of course but overall this was neat.

Sense I am the only one who apparently understands it as of yet, I say it was cool.
 

Eternal

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Originally posted by Giovanni Casanova
Loud sobbing followed by repeatedly bashing my head against a door frame worked okay for me.

Just FYI.
Tried it. Parents are sending me to a pysc hologist tommarow for the sobbing and now I am taking Tylenol for my headache...
 

rgeere

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Ok, I don't understand something in this formula.

U stands for concave, right?

also, I can't figure out how you got 1.39 utils from In[20/(2*5) + [20/(2*5)]

I tried using PEMDAS, but apparently that didn't work either. I'm not content with just (0.693+0.693) either to find an answer.

Please help!
 

Giovanni Casanova

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Originally posted by rgeere
Ok, I don't understand something in this formula.

U stands for concave, right?

also, I can't figure out you got 1.39 utils from In[20/(2*5) + [20/(2*5)]

I tried using PEMDAS, but apparently that didn't work either. I'm not content with just (0.693+0.693) either to find an answer.

Please help!
Give it up, please.

You're going to make my head explode.
 

Giovanni Casanova

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Originally posted by crazykid
Tried it. Parents are sending me to a pysc hologist tommarow for the sobbing and now I am taking Tylenol for my headache...
You know what makes me laugh? This thread on the same page as the thread that says... "The problem with making this a science"
 

Cheiradawg

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Originally posted by rgeere
Ok, I don't understand something in this formula.

U stands for concave, right?
Wrong

U is the symbol for untilty units.

also, I can't figure out how you got 1.39 utils from In[20/(2*5) + [20/(2*5)]
In[20/(2*5) + [20/(2*5)]=ln(4)=1.39
 

Lancer

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What?.. I'm friggin confused.
 

Giovanni Casanova

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Originally posted by Lancer
What?.. I'm friggin confused.
Join the club. We had T-shirts made.
 

Eternal

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Originally posted by Giovanni Casanova
Join the club. We had T-shirts made.
"I survived reading this post and all I got was this lousy t-shirt" shirts are now going for $10 at the Don Juan Gift Shop. All proceed's go to condoms.
 

rgeere

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T = 20 ; Free time per week in hours
t = 5 ; time per date
tt = ? ; time per non-date
D = 2 ; number of dates (concave)
N = 2 ; number of non-dates
U = Utils
O = equal to time spent doing non-date activities. (concave)
IL = interest level

tf = T - [D(t)] = Half of the equation
tt = tf/2 = Amount of non-time per week in hours

tf = 20 - [2(5)]
tt = tf/2
tt = 5
T = Dt + Nt ------> 2(5) + 2(5) = 20
U = Ind + InN ----> In[20/(2*5)+In[20/(2*5)=1.39
IL = InD ---------> 0.693
O = 0.693


tf = 20 - [2(4)]
tt = tf/2
tt = 6
T = Dt + Nt ------> 2(4) + 2(tt) = 20
T = Dt + Nt ------> 2(4) + 2(6) = 20
U = Ind + InN ----> In[20/(2*4)+In[20/(2*6)=1.43
IL = InD ---------> 0.916

Ok, had to rework the formula, still don't understand how to work the utils, but I atleast get the punchline now :)
 
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