M .sessions/nvim_config.vim M .task/backlog.data M .task/completed.data M .task/pending.data M .task/undo.data A Class_Work/nuce2101/exam2/2101_Exam_2_2025.pdf A "Class_Work/nuce2101/exam2/Fundamental Kinetics Ideas_Rev_17.pdf" A "Class_Work/nuce2101/exam2/Simplified Parallel Coupled Reactors Rev 8.pdf"
86 lines
3.9 KiB
TeX
86 lines
3.9 KiB
TeX
\documentclass{letter}
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\signature{Dane}
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\address{769 Shady Drive East \\ Apartment 303 \\ Pittsburgh, PA 15228}
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\begin{document}
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\begin{letter}{Brian Sabo \\ 6 Windsor Way\\ Coraopolis, PA 15108}
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\opening{Hey Brian,}
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I was so pleased to receive your letter. To be honest with you, I don't think I
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have ever received a hand-typed letter before in the mail. It was a nice break
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from the usual impersonal text messages the modern day is used to.
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I actually have a great story for you about a challenging class I took, and
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how it frankly changed my career path.
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I was in my junior year of my mechanical engineering degree when a graduate
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class called 'Linear Algebra for Machine Learning' was announced it would be
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offered. It was taught by a new assistant professor in the department named Ben
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Erichson. He was more of a statistics background, so I was very curious how the
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class would be taught. Plus, who isn't interested in machine learning?
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Let me tell you about an early hiccup in that class. Did you know that the least
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squares estimate, a.k.a. a linear fit, can be written like this?
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\begin{equation}
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\min_{\mathbf{x}} (\mathbf{A}\mathbf{x} - \mathbf{b})^T(\mathbf{A}\mathbf{x}
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- \mathbf{b})
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\end{equation}
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where $\mathbf{x}$ is the set of parameters, $\mathbf{A}$ is the input data, and
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$\mathbf{b}$ is the measured output. Basically, you choose $\mathbf{x}$ such that you
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minimize the error when you multiply it by the input and subtract the expected
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output. You can get the best linear estimator by doing:
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\begin{equation}
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\hat{\mathbf{x}} = \left( \mathbf{A}^T \mathbf{A}\right)^{-1} \mathbf{A}^T
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\mathbf{b}
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\end{equation}
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If you do it for a two dimensional case, you'll find you get exactly the result
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a linear fit in Excel will give you.
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Anyways, the derivation of this and the proofs were all in the first 60 minutes
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of class. My cocky ass didn't even know you could write vectors as bold small
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letters at that point. This class became the most difficult class I had taken to
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that point. But, in the struggle that class presented, the learning of difficult
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concepts provided me a sense of accomplishment and satisfaction that no other
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class previously had. I knew at that point that I needed to find somewhere I
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could keep learning and tackle hard problems. For me, that was a PhD. I don't
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use the material from that class on a day to day basis, but I still think about
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it a lot.
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So let me answer your question. When it comes to focusing on a concentration,
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taking more harder classes or taking the easy road, I say take what classes you
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find \textit{interesting}. Even if those classes are "difficult", they will be
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easy because you won't mind working on them. To that end, I don't think
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certificates or concentrations are too important. I'd ask your dad if he cares
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about a concentration when hiring someone, or would rather have someone who's
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curious, versatile, and challenges themselves.
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There is another important angle to consider when choosing classes. Certificates
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and concentrations are attractive. But, consider that if you're choosing between
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a class that'll give you a subtitle on your degree and one that you're curious
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about, remember that this is the \textit{only} time you will get to choose. When
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you finish school, you won't have an opportunity to take that 'interesting'
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class again, or really any class. Cherish the fact that you're able to pursue
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different courses now.
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Workload be damned. You're a very smart guy---you'll figure it out. If you want
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to do great things, they won't come easy, but they won't come at all if you
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don't push yourself. It's a privilege to be able to do this difficult work.
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\closing{Your cousin and friend,}
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P.S. Proofread your prose. You have typos in there! Most people will only know
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you through your writing, and you don't want to give a bad impression.
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P.P.S. I love the Leo picture and am keeping it in the office :)
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\end{letter}
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\end{document}
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