Recent content by bloynoys

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    How Should Manage Be Represented in an ER Diagram for a Video Rental Company?

    I am doing a ER Diagram for a class and having a lot of trouble with a specific piece of the sentence. Anyway, here is the business requirements we are diagramming: The video rental company has several branches throughout the USA. The data held on each branch is the branch address made up of...
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    Data Analysis: Automating Distribution Comparisons from Daily Stats

    Hey guys, I have a question of how to go about answering a question. I am trying to decide what coding/database language to learn next (most likely SQL with some access thrown in), but have an overall question. I am looking for an application or way to crunch daily statistical updates, then...
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    7 coins - probability over a dollar

    Yeah pretty clear it isn't close enough to normal. From just checking how many coin amounts are over 100 a few times it is always between 8 and 9 percent pretty far off from the 11-12 that it would be with the normal distribution.
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    7 coins - probability over a dollar

    Alright, I wanted to check this fast so what I did is just write a simple program in Java to generate random numbers between 1 and 4 and then if statements to create the cent amount after 7 coins. I ran that 50000 times and got this histogram. Do you think this is approximately normal? It...
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    7 coins - probability over a dollar

    I am not. I am about to start my final semester of undergraduate stats education (have stats 2, stochastic processes and multivariate analysis this semester) but so far we haven't gotten to things like that. Any reading or hints you would suggest as I try to learn about these things? Not a big...
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    7 coins - probability over a dollar

    Is there an easy way to simulate this in R or similar? It would be interesting to see what kind of distribution it comes out as. I would hope the pennies are able to "normal" it out but hard to know.
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    7 coins - probability over a dollar

    Yeah I tried to apply the continuity correction to the z calculation, so it would basically move the mean to 100.5 which is what gave me the answer that I had in the first post. Does that look right to you?
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    7 coins - probability over a dollar

    Alright my brother posed this question to me tonight. You have 7 coins (for this sake we will go with the "normal" coins, penny, nickel, dime and quarter) and we are trying to find the probability that a person has over a dollar in coins. So basically I did it and just wanted to confirm my...
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    Intro to Analysis (Differentiation)

    May be a dumb question but we know there is a limit at b, but trying to say if it is differentiable. How can we make the leap that there is a limit at b to that it is differentiable at b? I am following all of your logic (hopefully!) but that is the part I am hung up about. Thanks!
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    Intro to Analysis (Differentiation)

    Alright I have been working on this proof all dayish trying to get everything work out right. I have for my plan: Suppose x<c<b We will prove f'(c) has a limit m at b by showing that for every ε>0 there exists an δ>0 so that for every x in (a,b) 0<abs(x-b)<δ where abs(f'(c)-m)<ε...
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    Intro to Analysis (Differentiation)

    So I can say that because f'(x) has a limit at b the function limit x->b (f(b)-f(x))/(b-x)=f'(b)? So a proof would go something like: We will prove f is diff at b by showing that f'(b)=f'(b)=limit x->b (f(b)-f(x))/(b-x). Since f'(x) has a limit at b, we know limit x->b...
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    Intro to Analysis (Differentiation)

    Hmm. How would I go about doing that? I know by the mean value theorem there is a c in (a,b) that is satisfied by f'(c)=f(b)-f(a)/b-a but how can I show that since f'(c) exists f'(b) exists since it is not for every c in the interval?
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    Intro to Analysis (Differentiation)

    Homework Statement Prove or disprove: Suppose f:[a,b]->R is continuous. If f is diff on interval (a,b) and f'(x) has a limit at b, then f is diff at b. Homework Equations We say that f is differentiable at x0 to mean that there exists a number A such that: f(x)=f(x0)+A(x-x0)+REM...
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    Intro to Analysis (Boundedness of Cauchy)

    Alright I am following what you are saying but get stuck at: abs(an-am) ≥ abs(an) - abs(am) Then I do not know how to make it bigger than one.
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    Intro to Analysis (Boundedness of Cauchy)

    Homework Statement Prove the Boundedness Theorem for Cauchy Sequences by a contrapositive argument. Homework Equations The Attempt at a Solution If {an} is not bounded then {an} is not a cauchy sequence. We will prove that {an} is not a cauchy sequence by showing that there...
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