Semester page for ECON4120 - Autumn 2018

As of 45 mins before the review lecture, I have received no requests. I will poll you at the beginning of the session, and then I plan to go on with

• some general considerations: what you are "allowed to know"  etc., no need to quote question, no need to cite book pages ... example at the end.
• spring 2018 problem 1,
  • then say something about "other common question types for this topic",
• spring 2018 problem 2
  • ... ditto
• on until the problem set is done
• a few words about other bits and pieces: change of base (recall TP!), homogeneity/homotheticity, higher order appr's, elasticity of substitution, 

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So above I said "example at the end". Here is one: You MUST check whether you are allowed to use l'Hôpital before you apply it. On the other hand, you need not show that a function like ln(x(1-x)) is continuous...

It's about time that the schedule is final :-)

• Taylor won't take all Wednesday, so the rest of the time will be spent on reviewing integration and differential eq.'s.
• A review lecture is announced for Tuesday 27th at 1200.  Three hours allocated just to be sure we don't get thrown out. That lecture will start on the spring 2018 exam ...
• ... and luckily one of you has already helped debug the solution. If there is no "typewriter-font" notification of bugfix on page 1 in your solution document, please reload.
• Nils will not be available next week. Conference, has promised to present something involving a nasty partial differential equation system, and is busy tearing the hair off his head.
  _{(Yeah, the trouble is the limiting behaviour at zero extraction, how could you guess?)}

Nils

A note is uploaded, I put it under "seminar" material because that is where all other solutions are.

It is sketchy; it was originally written as guidelines to the graders, and then I filled in some bits before I uploaded it. As the first couple of lines say, an exam paper should not look like this.

You are probably wondering how it relates to what you could expect on an exam, so let me give a few comments: 

1. (a) Putting up a trap that invites you to taking logs of negative numbers is a bit nasty, and better suited for a "check before using l'Hôpital!" heads-up problem than for an exam. But questions like the first - a limit where you get 0*0=0, just to see if people check that - have been given. 
   Also, both signs of a real constant: again, many papers make assumptions that are not in the problem. Read the problem!
   (b) AFAIK, a problem like this - with x-dependent base number - has not be...

So lectures are on schedule, and the previously announced seminar assignment does not need any changes.

And, the TP review will be on Friday - but note, we had to change the room! The schedule is updated.

Check Canvas: you should be able to see by now.

If you need to get explained a topic and a half, then both Tuomas (room 1143) and Nils (room 1243) are here today - or by appointment. We are not that scary.

So the graders and the administration managed to get this out before close of business, rather than Monday. (We kept the resubmission deadline as it would have been if we had to wait until Monday morning though.)

For resubmission, you should resubmit a complete paper including any parts that were already good (and you may of course copy those from the first version.) Although it is suggested to write by hand, there is nothing wrong about copying a typeset part from your first and supplementing with a handwritten part.

One more thing: for a couple of approved papers, you might need to reload to get the complete feedback. (No verdict changed, do not worry!)

We had a look at it, and you should be able to do the problem set as announced. 

Also, I got a few questions on when you get your TP results ... nothing can be promised, but it looks like it could be at the beginning of next week.

A few updates:

• Tuesday lectures moved to ES Aud 7 (same room as Wednesdays), time unchanged. Effective the upcoming Tuesday 23rd.
  (We just found out that the lecture series that occupied it, is done, so we grabbed the opportunity to move home. Say goodbye to Store Fysiske and hello to the same docucam as Wednesdays.)
• Draft schedule for the rest of the semester posted: lecture topics and problem assignments all updated.
  Unfortunately, the publishing system still has its shenanigans: it inserts "undefined" between paragraphs. I cannot delete it, as it is not in the HTML source sent to the system.
  "Draft" means that there could be changes still.

We have to make some changes to the schedule:

• Tomorrow's workshop is relocated to P.A. Munch's hus. This change is already made in the schedule.
• Next week's workshop is moved to Friday - same hours and room as tomorrow. Change already implemented in the schedule.
  The reason for this change is that with only three seminars left, we need that problem set to include some integrals. We are aware that this is close to the seminar, but I found this to be the lesser of two evils.
• The Tue 13th workshop: now changed from "probably nothing" to term paper review. (There is a need for that.) It might be possible to do it slightly earlier, if you have strong opinions. 
• We have to reshuffle some details in the lecture schedule, but - because the system messed up last time we tried to do things to the "lectures" section - that will not be done until tomorrow....

Remember the TP deadline!

• As mentioned: write by hand! If you cannot scan any other way, use your cell phone camera - but too high picture resolution -> upload trouble.  And, please combine all to a single PDF.

No workshop today - moved to Friday!

• And just to confirm: seminar problems are as announced.
  (If you think #38 is a bit loose worded, I kind of agree.)

Uploads for this week updated (same URLs as before)

• Differentiation in eq. systems will take (quite) a bit of tomorrow. Relevant: updates from slides 14 on in "today's" document. (Hopefully reasonably bug-free, but slide 17 is not the most beautiful that mathematics has to offer.)
• Other updates: bugfix p5, footnote on language p7, and I typed in today's example on p12-13.
• "Tomorrow's" slides also updated. Luckily: less material!

Tuesday: review part on screen. Cookbook on screen. Keep cookbook on screen and give examples on the board. Might supplement this with handwritten examples afterwards.

https://www.uio.no/studier/emner/sv/oekonomi/ECON4120/h18/lecturenotes/econ4120LecDifferentialsEqSystems-preview.pdf

Draft for Wednesday uploaded as well: 
https://www.uio.no/studier/emner/sv/oekonomi/ECON4120/h18/lecturenotes/econ4120LecElastSubst-preview.pdf

... yes, reuploaded 19:28, so if you managed to get it before that: please reload.

There are some changes to relative to the Wed@1AM version, and the first of them will be elaborated after the list:

• The "find an expression for" clarification on slide 18 likely asks for too much in certain cases (though not the example given that page). Good news: "less to do". Bad news: further clarification needed.
  See brief explanation given below - and examples next week.
• New: 31 and 32 have calculations from Wednesday's class
• Bugfixes: fixed numbers in last line p30, misleading wording about what the cofactor is (last line p27), added the word "inverses" in 2nd bullet item p22 due to question in class. 
• Slides 9, 16, 23, 24 now clearer about what was less stressed in class. (That reflects priority.)
• Some Tue-to-Wed changes no longer indicated. Some of the above-...

Rather than a separate file for Wednesday, I updated the "lecture 5" slideset:

• Same link, just overwritten; please reload.
  Expected to be updated after tomorrow with scans. It is Aud7, so I can write and use the docucam.
• Updates and bugfix in "Tuesday's" part largely indicated in magenta colour. Might be removed in the final version.
• New slides "early" in the document: 5 and 7 (example variations etc. mentioned in class). 
  New slides "with Tuesday material" later too, but I'll point that out in lecture.
• There might be (#¤%&stupid) bugs here too, of course - especially considering the time of "day" I post this, but for it to work as "preview" you need to have it by Wednesday morning. 
• Wednesday will start where we left off Tuesday: the inverse. Slides 14 & 15 repeated, with a brief walkthrough slide 16 (which is rather a "see if you can follow this by yourselves afterwards" thing). Then a few things I h...

Uploaded: the draft revised into full slideset for tomorrow - and most of Wednesday, I guess.  Same URL. If you reload, you should get a version which on slide 1 starts with "Have" and has a "To follow today: More of everything", and then a  "Question for you: anything you need reviewed on Wednesday?"
- please form an opinion on that question!  ("Nothing" is a valid opinion.)

Problems for next week: as posted, actually! Just take note: 

• It is the entire 139, but with part (b) done by a different method (given in today's upload, but might not be lectured until tomorrow). 
• 34 is indicated as "possibly low priority"; it does not take long time if you spot it.  But if you don't ...