Midgley, Christopher - Pointless twaddle and meaningless diatribes
https://blogs.warwick.ac.uk/midgleyc
In which I post about whatever catches my fancy, and then give up and do nothing for several years, my last post a statement on how I have much to write about and will inevitably find the time...later.en-GB(C) 2021 Christopher Midgleyhttps://blogs.law.harvard.edu/tech/rssChristopher MidgleyChristopher MidgleyWarwick Blogs, University of Warwick, https://blogs.warwick.ac.uk120Exam Reflection - Results! by Christopher Midgley
https://blogs.warwick.ac.uk/midgleyc/entry/exam_reflection_results/
<p>Looking back at previous entries, I believe my expectation for the marks I’d receive goes something like this: <br />
Intro to Geometry >> Japanese writing > Probability B = Probability A > Games & Decisions > Geometry and Motion > Differential equations > Linear Algebra > Japanese Oral >> Analysis<br />
In fact, the results (final exams only, Japanese is blended) went more like this:<br />
Geo & Motion > Introduction to Geometry > Probability B >> Probability A > Japanese > Linear Algebra > Analysis > Differential Equations > Games & Decisions</p>
<p>So the most surprising ones were Geo & Motion, where I scored far, far beyond what I expected (I suspect mark adjustment) and Games & Decisions, where I scored some distance below. I also underestimated my Analysis mark by around 50%.</p>
<p>Details: I took 145.5 <span class="caps">CATS</span>, scored an average mark (in the final exams) of 78, with a sdev of 10.9, which is pretty damn large, really.</p>
<p>Individual comments:<br />
For GeoMo I eschewed doing past papers, instead reading through the notes and worked examples, and doing some of the worked examples. This paid dividends – I was very well prepared. It also didn’t take that much time. I feel having the worked examples helped tremendously. Unfortunately, most modules lack these.</p>
<p>The difference between my Prob B and Prob A mark is around ±10% – quite large. While I suspected I’d done better initially in Prob B during the exam, I thought I’d corrected my mistakes. Not having lecture notes hindered me in this course: my own notes, despite apparently being in chronological order, wibble and wobble all over the place. As an example, I didn’t know (and still don’t!) anything about bivariate conditional/marginal distributions – I presume we looked at it briefly, and I skipped over that section.</p>
<p>Finally, a graph of exam marks against date of exam.<br />
<img src="http://blogs.warwick.ac.uk/images/midgleyc/2011/06/30/graph.png" alt="" border="0" /><br />
The graph shows a few things: for one, my belief that I was doing better on exams as time went on looks pretty wrong from here; second, the four day exam stint didn’t appear to have much effect on my marks despite the wild zagging between below 70 and above 90%, and finally that looking at the rest of my marks the coursework propped me up a fair bit. Geometry & Motion was the only module where I did better in the exam than the coursework.</p>
<p>I’ll conclude by saying that my mark for Programming for Scientists, a cool 95.75%, narrowly beats out Geometry and Motion for the top spot. That course was pretty ridiculous.</p>Exam ReflectionThu, 30 Jun 2011 14:20:18 GMTChristopher Midgleyhttps://blogs.warwick.ac.uk/midgleyc/entry/exam_reflection_results/#comments094d73cd308d95b70130e0ebf8a215c71ST114 Games & Decisions Exam Reflection by Christopher Midgley
https://blogs.warwick.ac.uk/midgleyc/entry/st114_games_decisions/
<p>I feel I’ve become both more relaxed and more flippant as the exams went on – I also feel that generally I performed better on the later ones. Having questions in which a girl believes she can predict her marks down to the last percentage point are more fun to do.</p>
<p>This was one of the exams, like Analysis, in which I did more than the bare minimum of questions: i.e. all 3. Unlike Analysis I was able to give complete answers to all three.</p>
<p>I began confidently with the question on Games, but couldn’t remember the exact graph method, flipped and flopped around, tried to work out the final answer a different way, got something else, gave up and moved on.</p>
<p>I then moved back to answer the first question, drew a tiny decision tree, and gave an answer on discounting a 69 vs a 70, assuming you have your estimated marks perfect. This part was fun.</p>
<p>I then rushed through the second, trying to recall definitions, and giving an example of a man who is certain that any given coin comes up both heads and tails at the same time (he’s wrong). For the last part, I misread min as max (NTS: don’t do that), forgot how the log function worked, forgot how functions in general worked (I saw min(log(r),100) as min(log(min(r,100)),100)), but I think I was able to sort it out. Narrowly finished on time. Enjoyed the exam. Probably worse than Prob, but around there. More fun, though.</p>Exam ReflectionTue, 14 Jun 2011 10:35:10 GMTChristopher Midgleyhttps://blogs.warwick.ac.uk/midgleyc/entry/st114_games_decisions/#comments094d73cd308d95b701308db81807000f0MA134 Geometry and Motion Exam Reflection by Christopher Midgley
https://blogs.warwick.ac.uk/midgleyc/entry/ma134_geometry_and/
<p>Like most of the exams that weren’t Analysis, this exam also went well. I wasn’t quite able to derive the final result on one of the questions and my notation was messed up because I didn’t realise that r’ with respect to x and r’ with respect to y would be different and so my attempt to save on writing instead confused the whole situation.</p>
<p>I eschewed the normal “do past papers” style of revision because there are no answers, and doing past papers without answers is even more of a waste of time than doing past papers normally. And doing past papers without answers after the syllabus has changed is even more of a waste of time than that.</p>
<p>Instead, I read through the lecture notes again, doing some of the examples. These lecture notes incidentally happen to be very readable. And concise. I also did some of the exercises from the example sheets, because those had answers. I also read through answers for the questions I couldn’t be bothered to/didn’t have time to do (this was the morning of the exam). It’s very useful to have a lot of worked, short example questions. I can understand a rationale for not giving students example sheet answers (if you never change the questions, they could sell/distribute them to new first years) but it’s still a pain.</p>
<p>As for how it went – probably better than Linear Algebra, but worse than Probability. I did enjoy this course, though.</p>Exam ReflectionThu, 09 Jun 2011 15:33:20 GMTChristopher Midgleyhttps://blogs.warwick.ac.uk/midgleyc/entry/ma134_geometry_and/#comments094d73cd3003a6240130750947d131b00MA133 Differential Equations Exam Reflection by Christopher Midgley
https://blogs.warwick.ac.uk/midgleyc/entry/ma133_differential_equations/
<p>From this I’ll conclude that I’d memorised less than I thought I had, but I was able to derive more than I thought I would be. So overall +.</p>
<p>I wasted ~ 20 minutes due to pointless mistakes – swapping x and y,not changing a sign through an entire bracket…but I found them in the end. There were likely more I didn’t see. I also wasted a lot of time trying hopelessly to figure out how to answer certain questions :)</p>
<p>Overall I think it went better than Linear Algebra but worse than probability. Only one more exam to go until I get a break of at least a day! Hooray!</p>Exam ReflectionWed, 08 Jun 2011 11:08:11 GMTChristopher Midgleyhttps://blogs.warwick.ac.uk/midgleyc/entry/ma133_differential_equations/#comments094d73cd3003a62401306ef02b812ea70MA125 Introduction to Geometry Exam Reflection by Christopher Midgley
https://blogs.warwick.ac.uk/midgleyc/entry/ma125_introduction_to/
<p>The exam could not feasibly have gone much better. The questions – straightforward, for the most part, but entirely possible. <span class="caps">A 14</span>-mark walkthrough of proving Ceva’s theorem – a proof I already knew. Could have done with being a bit harder, I guess.</p>
<p>I didn’t do anywhere near as much revision for this as for other courses, but then again the course is also significantly shorter.</p>
<p>I think my reading Euclid long ago has aided my ability to construct proofs in some way, but considering it was “nonexistent” before that I can’t say by how much. I still believe it was useful, though.</p>Exam ReflectionTue, 07 Jun 2011 14:28:11 GMTChristopher Midgleyhttps://blogs.warwick.ac.uk/midgleyc/entry/ma125_introduction_to/#comments094d73cd3003a62401306a80ec0c2d700MA1312 Analysis II Exam Reflection by Christopher Midgley
https://blogs.warwick.ac.uk/midgleyc/entry/ma1312_analysis_ii/
<p>So, that went poorly.</p>
<p>Could I have done more revision? Yes, most certainly. Would the sort of revision I had intended to do have helped? No.</p>
<p>Points:<br />
I missed cases or failed to accurately read questions in some cases. There’s not much help for this – it’s something I try not to do :)<br />
I forgot how to prove the latter part of the Extreme Value Theorem, despite only doing it the day before.<br />
I couldn’t see how to solve some questions.</p>
<p>Improvements:<br />
I should become more comfortable with Taylor polynomials to the level at which I’m willing to use them even if they aren’t explicitly specified. Currently I avoid them out of some vague sort of discontent.</p>
<p>Current mark expectation:<br />
Japanese writing > Probability B = Probability A > Linear Algebra > Japanese Oral > Analysis</p>Exam ReflectionMon, 06 Jun 2011 12:18:29 GMTChristopher Midgleyhttps://blogs.warwick.ac.uk/midgleyc/entry/ma1312_analysis_ii/#comments094d73cd3003a624013064e3cef029a60Linear Algebra MA106 Exam Reflection by Christopher Midgley
https://blogs.warwick.ac.uk/midgleyc/entry/linear_algebra_ma106/
<p>This year’s exam was written by a different person (Daan Krammer) to the previous years’ and so naturally it differed. In particular, the last question wasn’t a series of true/false, which I preferred for easy marks and occasional interesting point (and nice tricks – an identity map is not always an identity matrix, for one).</p>
<p>As before, I did past paper questions, got bored quickly, and flipped through the markschemes the morning of the exam. I did find a much better (shorter) “ranks are equivalent” proof than the one I’d previously learnt, so it wasn’t a complete waste of time.</p>
<p>The first question was standard fare even for previous papers. One question was awkwardly phrased, so I decided to take it literally. The second dealt with surjectivity and injectivity – a new topic for exams, but one I’m pretty sure was dealt with in assignments. The third contained a matrix proof where I couldn’t be bothered to memorise the subscripts involved, in the hope it wouldn’t come up – ah well. The fourth contained a horrible “find this 5×5 matrix determinant” that I got terribly wrong. The last part of four was an interesting original proof in which I used parts of my old rank-equivalent proof, mostly relating to bases of row spaces and the like. The fifth, which I didn’t do, was full of questions that would be easy to work backwards. I was turned off by the hint to the second part, which I couldn’t comprehend in the time limit.</p>
<p>Overall I think I did pretty well, but I may have got large swathes of it incorrect. Nonetheless, it was a more interesting exam than the previous ones – original proof questions are very fun if you get them.</p>Exam ReflectionThu, 02 Jun 2011 19:27:46 GMTChristopher Midgleyhttps://blogs.warwick.ac.uk/midgleyc/entry/linear_algebra_ma106/#comments094d73cd3003a624013051d365831fbf0Probability A/B - ST111/2 Exam Reflection by Christopher Midgley
https://blogs.warwick.ac.uk/midgleyc/entry/probability_ab_st1112/
<p>Probability was the first Maths exam I took this term, on the 31st. I had a bunch of past papers, but the lecture notes were still incomplete. No answers were provided for any assignment bar the last, but I got most of the marked questions right, and probably most of the rest of the questions as well.</p>
<p>I did…around 3 past papers of the old style, and one or two newer ones. I skipped some of the questions of PGFs and the like that aren’t in the syllabus. Before the exam, I felt like I’d done enough revision – more that I didn’t feel like doing any more.</p>
<p>The exam itself was split into two parts: A and B. A bore some resemblance to past papers but had a fair few questions on the theory, the like of which hadn’t come up before. I was glad I picked Games & Decisions at this point, as the extra work on basic probability helped.<br />
I think I did pretty well on Prob A, overall. I was able to answer all of the questions, which is a good sign. I wasn’t exactly sure what “basic set operations” were, though, especially when Probabilities are added to the mix.</p>
<p>Probability B was different. I couldn’t remember how to find joint or marginal densities, the version of Markov’s inequality was different to the one I knew, and I thought that a question asking for an expected number of offers relating to “a” (nonspecific) cdf F meant to average over all possible cdfs, so one question was right out. 4 past paper sub-questions came up, so that was very convenient. Couldn’t remember exactly how to find P(X < Y) given distributions, did a double integral that seemed reasonable at the time.</p>
<p>Overall, I think this exam went very well, although as it was the first I did more revision on it than I have for many other subjects (there were more past papers available, too). I think I did <em>too much</em> revision – I could quite easily have done substantially less and got a similar mark. I am planning on doing more Stats later, though, so no harm.</p>Exam ReflectionThu, 02 Jun 2011 19:13:23 GMTChristopher Midgleyhttps://blogs.warwick.ac.uk/midgleyc/entry/probability_ab_st1112/#comments094d73cd3003a624013051c638851fba0