2. Preferences and Utility Functions

MIT 14.01 Principles of Microeconomics, Fall 2018
Instructor: Prof. Jonathan Gruber
View the complete course: ocw.mit.edu/14-01F18
KZbin Playlist: • MIT 14.01 Principles o...
This video focuses on the demand curve, derived from how consumers make choices, and the supply curve, which is how firms make production decisions.
Chapters
00:00 Title slate
00:11 Lecture Start
01:13 Model Assumptions
05:54 Indifference Curves
09:23 Four Properties
13:27 Real Example ( job search )
15:28 Utility Functions
18:31 Margin Utility
24:49 Marginal Rate of Substitution
30:13 Why graph's not concave
32:37 (Q) Addictives & MRS
34:31 Price of Different Sizes of Goods
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[@pallabibiswas3422]

Notes: Demand curve - how consumers make choices Decision making - Utility maximisation. Consumer preferences - what people want and budget constraints - what they can afford. Step 1 - Preferences - how do we model people’s taste - Unconstrained choices, money is no object, how do we think about what we want. Preference assumptions. Models are based on simplifying assumptions. Are they roughly consistent with reality or not? Completeness - We have preferences over any set of goods we choose from. Can’t say I don’t know how I feel about this. Transitivity - If we prefer A to B and we prefer B to C then we prefer A to C. Non-satiation/More is better - More is always better than less. Graph of people’s preferences. Indifference curves. Graphical maps of preferences. Suppose parents gave money before semester. Spent on two things - buying pizza or eating cookies. 2 dimensional decision case. Consider 3 choices A. 2 pizzas and 1 cookie B. 1 pizza and 2 cookies C. 2 pizzas and 2 cookies. Assume - We are indifferent between these packages. Equally happy with all the packages. And also assume we prefer option C as more is better. One indifference curve between A & B because those are the points among which you’re indifferent. Indifference curve represents all combinations of consumption among which you are indifferent. You are indifferent between A & B and therefore they lie on the same curve. 4 properties that you have to follow from these assumptions: Prop 1 - Consumers prefer higher indifference curves = More is better. Package that has at least more of 1 thing than the other so you prefer it. As the curve shifts out you are happier because more is better Prop 2 - Indifference curves are downward sloping. Comes from Principle of non-satiation. Why does it violate the principle of non-satiation? You cannot be Indifferent about 1 of each or 2 of each. Prop 3 - Indifference curves never cross. Because in B & C, B is strictly better but they’re also on the same curve as A. You’re indifferent with A for both B & C but you can’t be indifferent between B & C because B is strictly better than C. Indifference curves crossing violates transitivity. Prop 4 - Only 1 indifference curve through every possible consumption model/ Only one indifference curve through every bundle. You can’t have 2 indifference curves in the same bundle because of Completeness. If this did happen you wouldn’t know how you felt. You may feel indifferent but you can’t say you don’t know how you feel. Example - year op as a grad student who had to decide where he would accept the job. I am indifferent but I care about 2 things - school location and economics department quality (quality of my colleagues and the research that’s done there) One is from Princeton and the other is Santa Cruz (not as good as economics department). 3rd offer - IMF research institution in DC and had a lot of good colleague and DC is way better than Princeton. Worst quality than Princeton and worst location than Santa Cruz but it was still better in combination than these two institutions. Utility Functions - Mathematical representation - Every individual has a stable well behaved underlying mathematical representation of your preferences which we call utility function. 2 dimension - how do we mathematically represent between pizza vs cookies. Utility function is no. of slices of pizza vs no. of cookies. U√P*C. What is Utility? It doesn’t mean anything. Its not a cardinal but an ordinal concept. Assume you can rank your choices in many dimensions. Weigh different assumptions so you can rank them when you need to choose. Marginal utility - 1 cookie and then the value or utility of the next cookie. Marginal decisions. Once you eat an cookie, do you want the next unit/cookie/pizza? Key feature - Diminishing Marginal Utility - the more of you’ve had of a good the less you would want the next unit. No. of cookies holding constant pizza. If you’re having 2 pizza slices and you want to say what’s my benefit from the next cookie. Left axis - violating the above we graph utility. Eg. If you have 1 cookie your utility is 1.4; square root of 2 times 1. If you have 2 cookies the utility goes up = square root of 4 which is 2. You’re happier with 2 cookies but you are less happy with the second cookie as you were with the first cookie. The 1st cookie gave you 1.14 utility. What’s your happiness is measured in this graph of marginal utility. The next cookie’s utility is 2.059. Each additional cookie makes you less and less happy. Makes you happy as more is better but less happy as the 1st cookie. Remember you always want more cookies. You can say that the 11th will make you barf. But in economics you can give it away or save it for later, worst case you can throw it out, but you always think more is better. Utility function can never be negative, as its an ordinal concept, and is always positive as you get some benefit from the next unit. Indifference curves are the graphical representation of what comes out of utility function. Slope of the indifference curve is called marginal rate of substitution. The rate at which you’re willing to substitute one good for another. Substitute cookies for pizza. dp÷dc = marginal rate of substitution. I am indifferent between point A & B. Over here 1 slice of pizza = 1 cookie. Marginal rate of substitution is -2. I am ready to give 2 pizzas for 1 cookie. When we move from B to C the MRS is -½. Now I’m willing to give only 1 slice of pizza for 2 cookie, because we don’t want cookie as much due to diminishing marginally utility. MRS is always diminishing, it has to. Slope will always be falling. How MRS relates utility function; MRS=DP÷DC= -MUc÷MUp (c - cookie and p - pizza). MRS tells you how relative marginal utility evolves as you move down the indifference curve. When you start at point A, you have lots of pizza and not a lot of cookies; here your marginal utility is small. Marginal utility are negative functions of quality, the more you have it the less you want it. As you move along the indifference curve, you’re more willing to give up the good on the x-axis to get the good on the y-axis. Implies that indifference curves are convex to the origin. They’re not concave, they’re either convex or straight. It can be linear. What would happen if indifferent curves were concave to the origin? From point A to B leaves you indifferent so You can give 1 slice of pizza to get 1 cookie, starting to give 4 pizzas for 1 cookie. From 2 and 3 you are willing to give 2 pizzas for 1 cookie. This violates principle of MU and MRS as pizzas should be more valuable as you have less pizza now. Addictive decisions - Smoking. Utility function shifts as you get more addictive. The next will be still be worth less. But as we’re addicted the first cigarette will be worth more and more to you. When you wake up feeling crappy the first cigarette will be good to you but the next morning you wake up feeling crappier and wanting the first cigarette more as people get habituated to certain levels. For drugs its not about diminishing MU but different underlying products used in the drug. Example - Prices of different sizes of goods. Starbuck tall coffee for $2.25 and the next one for 70 more cents. McDonald - Small is $1.22 but for 50 more cents you can double the size. Why do they give twice as much for much less than twice as much money? Its all about diminishing MU, you’re desperate for the first soda on a hot day, but not twice as much for the next glass. Those prices reflect market’s reaction to diminishing MU. If you think about demand and supply, the demand for 1st 16 ounces is higher than the demand for the 2nd 16 ounces, but the cost to produce the drink is the same. Since the demand for the next 16 ounces doesn’t shift twice as much, you can only charge 50 cents for the next 16 ounces. Price increments get smaller because of diminishing MU. Buying in bulk from Costco is not much less than buying single units from supermarkets as the price gap between the soda example. Even though you might get thirstier later in the day for another glass of soda, they won’t let you walk in with the first cup you bought from them. Eg. Fenway small soda - $6, bigger soda - $8, refillable soda cup - $10. Can you bring the $10 refillable cup back to additional games? No.

[@tripurarikumar645]

Thank you Pallabi

[@jayagahlot6349]

Tx

[@ashutoshnagaria7559]

Thanks a lot

[@unknown4955]

thanksss

[@simonsays9974]

I have you for making me lazy and appreciate you

[@hollykm]

This is why I want to go to a great school like this one. Not because I'm some kind of genius, but because I think, with the right teacher, anyone can be a genius. And at schools like MIT, every teacher is equipped to teach effectively.

[@coryaw95]

Not necessarily

[@henryrugg4971]

The rarity and therefore the meaning of 'genius' surely becomes diminished if 'anyone can be a genius'

[@tradespacetech7162]

This professor works for UNC.

[@umapathiaragonda2880]

I really think he could have done it better

[@suindude8149]

Well said as I come accross the life of professorial I become utmost well in the case of the subject.I myself feel under high depth.

[@shubhammaheshwari1191]

Now I know the difference between MIT and DU. Not the curriculum but the faculty.

[@accountsequity5587]

DU?

[@marlonbrandoseyes1443]

@@accountsequity5587 Must be Delhi University

[@Ankit-fe7un]

@@pratikbhaumik2748 This is a stupid statement because "these economics" doesn't exactly apply to any market. But they give a general idea of how it would behave. The robusticity of a model depends on the assumption you make. Please watch the lecture instead of scrolling through the comment section first.

[@idiotofallidiots843]

@@Ankit-fe7un yes u are right. Chaos theory is what we should apply to Indian markets. Entropy of indian market always increases . Never decreases.

[@idiotofallidiots843]

Logic and roman system of science never works it completely breaks apart what we need is chaos theory.

[@ariellatheora3185]

This person makes me enjoy these lessons. I have to spend three semesters on Micro and Macroeconomics and I didn't understand as much as I do now when this person is teaching! For once, the marginal utility of these lessons doesn't diminish for me! Thank you MIT open course! And thank you, Professor Gruber.

[@draincel]

head

[@Lanareyy]

👑

[@tarafahey6217]

01:13 Model Assumptions 05:54 Indifference Curves 09:23 - - > Four Properties 13:27 - - > Real Example ( job search ) 15:28 Utility Functions 18:31 - - > Margin Utility 24:49 Marginal Rate of Substitution 30:13 - - - > Why graph's not concave 32:37 - - - > (Q) Addictives & MRS 34:31 Price of Different Sizes of Goods

[@callmejohn3222]

bless you

[@debaleena1234.]

Thanks ...

[@hollykm]

Thank you kindly

[@kaiqiyu6341]

Nice

[@mosesbrian5522]

☝️

[@user-ed7vz3xz6f]

Microeconomics L-2 A. Utility Curves A.1.Assumptions A.1.1. Completeness - You can mark preference on any item. Inversely, you cannot say you feel 'indifferent' about it. A.1.2. Transitivity - If A preferred over B and b over C then A is preferred over C. A.1.3. Insatiable - More is better than less. A.2. Draw Utility curves now: Ordinal and not cardinal metric (i.e., you cannot be certain about by how much A is bigger than B but definitely rank A and B) A.3. Properties A.3.1. Only one utility curve for a bundle - Completeness property (i.e., preferences cannot be uncertain or non-existent). A.3.2. Utility curves cannot cross each other - Transitivity (if crossed, A=B and A=C but A>C). A.3.3. Utility curves are negatively slopped - Insatiability (If positively slopped, More is equally preferable to less). A.3.4. Not concave to the origin - Violates Marginal diminishing utility (If concave, you'll be willing to substitute more goods of one type by an equal number of competitive goods when you have less of it). B. Marginal Utility B.1. The utility of the next unit of A relative to the amount of A you have now. Basically del(U)/del(A). B.2. Properties: B.2.1. Utility will increase but Marginal utility will be diminishing (Not concave to the origin). B.2.2. Though the Marginal utility is decreasing, the value must be non-negative. (Design Utility eqn accordingly). B.2.3. MRS (Marginal rate of substitution) = slope of the Utility curve = Marginal Utility of Item on the x-axis/Marginal Utility of item on the y-axis. B.2.4. Explanation of 3: delta A (the number of items A willing to be exchanged) is inversely proportional to the Marginal Utility of A at the given point for a given amount of item B. C. Other discussions: C.1. For additive items, it's not that the Marginal utility is increasing (it's diminishing in this case too) but the Utility function shifts. C.2. Why are price increments less than the proportional increment in the amount? - Refer Point 3 and 4 in Marginal utility. (Will be adding notes as I progress in the course based on my understanding of the material).

[@twinklegarg99]

Can you share the name of the material, you are using?

[@avinashprasad2]

Definitions and Notes 1. Assumptions: more is always better, there are no budget constraints for this class's thought experiments. 2. Indifference curves: An indifference curve is a graph showing combination of two goods that give the consumer equal satisfaction and utility. Each point on an indifference curve indicates that a consumer is indifferent between the two and all points give him the same utility. 3. Four properties of Indifference curves: (i) People prefer higher IC (ii) Indifference curves never intersect. (iii) Indifference curves are downward sloping (iv) Only 1 I.C through every bundle 4. Preferences: In economics and other social sciences, preference is the order that a person gives to alternatives based on their relative utility, a process which results in an optimal "choice". Preferences are evaluations, they concern matters of value, typically in relation to practical reasoning. 5. Utility: Economists use the term utility to describe the pleasure or satisfaction that a consumer obtains from his or her consumption of goods and services. It is a subjective measure of pleasure or satisfaction that varies from individual to individual according to each individual's preferences

[@schmetterling4477]

None of this has anything to do with smart shopping. The shopper with higher budget almost always gets the better price, which is basically an effect that is equivalent to a regressive tax.

[@rickandmorty2361]

@@schmetterling4477 Yeah sometimes Reality is way different than these textbooks can teach us!

[@schmetterling4477]

@@rickandmorty2361 Why do you assume that his bullshit came from an actual textbook (at least one worth reading)?

[@AsadAliShah89]

I really appreciate MIT open courseWare, helping me alot in learning my MicroEconomics Theory course

[@robbyosborne9708]

I'm getting addicted to these lecture videos. The way Dr. Gruber teaches Microeconomics is fascinating. He is so wise.

[@shujiezhang3494]

Prof. Gruber and his MIT students were on fire. What a terrific lecture and insightful Q&A.

[@ThanhTran-gb4pw]

For those of you doing the assignments and feeling like you've missed a lot with the math behind demand curves, you definitely have. If you're looking for a more in depth class that covers the math (which is quite important), I recommend the 2011 version of this course also on MIT open courses. The optional textbook also covers it if you prefer to read.

[@compassft]

Thank you. When you say the 2011 version, is 2011 the year?

[@notanikdey]

@@compassft yes

[@compassft]

@@notanikdey thank you!

[@anzumerkenist8717]

do you have a link? can't find it on yt

[@danielgrezda3339]

THANK YOU SOOO MUCH!!! I thought I was an idiot for being lost on the MRS problems, but I'm only stupid.

[@ankitvyas4373]

respected professor teaches in very simple manner believe me i am a biology student

[@LionGamingLive]

I love this professor. He explains stuff so well. I currently also have a eco class at my university (Leiden University) which is also quite a good university, but I always come here to watch his lecture to really understand the topic haha

[@abstractum1564]

planning to do my master's there, how much'd you recommend it?

[@krissp8712]

Wow, I didn't realise there was a new edition! I'd seen his last version from 2011 and it's really neat to see this one too.

[@maninderkaur3960]

Same here

[@chennrivero7644]

This lectures help me a lot in understanding economy concepts and theories. Thank you!! Also, I totally admire the class interactions.

[@hakunamatata7010]

these topics where the first topics in my microecomonics classes and i was so sad that i didnt understand them. I thought i was stupid or something since i had bad grades in my math classes at high school, but i understood everything quickly with this man, he is def a great teacher with amazing skills of simplification. Thanks for the open courses from one of the top universities! It is really helpful especially for those who can not afford to study in top rated schools

[@sinem3866]

Thank you Proffesor for letting this lectures online, I study my micro lessons with these lectures ^-^

[@georgemwanza6339]

Where do you study at?

[@user-vv2uz7zf2t]

@@georgemwanza6339 probably somewhere in turkey

[@georgemwanza6339]

@@user-vv2uz7zf2t I'm studying economics in Turkey too

[@oris2723]

Do y'all think Turkey's economy is getting bankrupt?

[@yunusemreyazc848]

@@oris2723 not gonna bankrupt but we are gonna have to have really really tough times because of the untalented people who manage the country

[@semidebahar8647]

Woah, simplifies everything to the core so you get a deeper understanding in every aspect. Heads up for the prof!

[@huonggianghoang3280]

really love the part where he explains MRS = - MUc/MUp!!!! I understood it intuitively and graphically! Thank you so much!

[@dynamisarian6576]

I wish our teachers could teach like that. Sooooooo helpful and simple .💜💜💜thank you so much😗

[@user-fh5ov4tu2j]

Whenever they present a concept i immediately look forward to the example because it makes so much sense

[@louisechristiansen3877]

Thank you so much for this excellent free education.

[@_Anti_Communist_]

Well explained and presented with simple but realistically-based examples!

[@lesliethompson1995]

This is an amazing resource for my Microeconomics for Policy Analysis course at the U of MN. Needed some help with my homework and found this lecture. Thanks MIT for posting this to help other students. Great lecture, very good examples and easy to understand. Thank you!!!

[@prajwalgowda7024]

hii

[@suindude8149]

Myself,it's time for post behavioural of post graduate.Thats really a privilege.

[@kateandrews6902]

# Preferences and Utility Functions NOTES - **Demand Curve** - represents how consumers make choices - **Supply Curve** - represents how firms make production decisions - Consumer decision making is a model of **utility maximisation**. Two components: - [1] **consumer preferences** - what people want - [2] **budget constraint** - what they can afford - In this lecture we are focussing on preferences - how do we model people's tastes? (Graphically) - A) Preference Assumptions: 1. Completeness - you have preferences over any set of goods. You can be indifferent 2. Transitivity - If you prefer A to B and B to C, you prefer A to C 3. Non-satiation - More is better than less (NOT that the next unit will make you equally happy!) - Indifference Curves represent all combinations in which you are indifferent - Four properties of Indifference Curves 1. Consumers prefer higher indifference curves (Principle more is better than less) 2. Indifference Curves are downward sloping (Principle of satiation) 3. Indifference Curves never cross (If IC crossed it would violate principle of transitivity) 4. Only one IC through every bundle (Principle of completeness) - Utility Functions (Mathematically) Utility is an ordinal concept - you use it to rank preferences. This function allows you weight the different elements of your consumption bundle Simple, but powerful way to explain decisions - Marginal Utility - Very important concept - it is a derivative of the utility function with regards to one of the elements - Marginal Utility of Cookies is the utility of the next cookie. - Compare with the question how many cookies do you want? (more difficult question) compared with do you want another cookie? - Key feature of utility functions: They will feature diminishing marginal utility. The more of a good you've had the less happiness you will derive from the next unit. - Marginal Utility is never negative - more makes you happier or at least indifferent - The indifference curve gives you the **Marginal Rate of Substitution** - the rate at which you are willing to substitute cookies for pizza. MRS is always diminishing. - **Marginal Utilities are negative functions of quantity - the more you have of a thing the less you want the next unit of it** - Indifference curves are convex to the origin - (a concave indifference curve would violate the principle of diminishing marginal utility)

[@getemmibang5984]

Thanks for sharing ☺️😊😊

[@vishnukanhan8809]

This is cool. I hope you have done this on all videos. 😂❤

[@berkadsiz2905]

So efficient and useful Intro Econ Courses, thank you for sharing these precious videos with us and also appreciate his help (thanks sir) , I easily understood the parts that I haven't understood in my real classes :-)

[@2late4coffee]

Same here, cheers dude :)

[@rakkhnaka]

Happy to see so many fellow Indians in the comments. It shows we are knowledge hungry. Its sad we don't have these kind of professors in India even in elite schools like IIT.

[@immanueljohn2410]

Yeaaah♥️🌝

[@sundargopal6973]

Great explanation. Im a data engineer trying to transition to economics field. This playlist is helping me understand the optics of economics. Thanks so much @MITOpenCourse and Prof. Jonathan Gruber.

[@suindude8149]

Myself also it's a great exposure to all of Commerce in healthier format.

[@randywhitmore7517]

Man, thought I was hooked on TED Talks...love these MIT lectures !

[@muhammad-amiindhimbiil6066]

The fact about Smoking is so true, Every single One Diminishes its taste after the othor one, and gives you a ton of problems that you were not having before. I like the fact that there is no big price different between the big giant Juice Drink and the Increase of their number. Because they know your appetite goes satisfactory after the previous one.

[@prachirawat1145]

He is a great teacher. I hven't seen such appreciation and encouragement from teachers.

[@charlespell7762]

Wow, this lecturer is amazing! Thank you MIT!!!

[@wordwords762]

Prof Gruber r the best thing that ever happened to me, thank you for posting

[@isexuallyidentifyasanapach4720]

Just watching some other lectures from different teachers just shows me how widely different the teaching methods are between them. My teacher for example never went into indifference curves for example when discussing utility.

[@muloongomachila3886]

Thank you for these videos. Easy to grasp and well explained.

[@mohammedrajib4995]

I’m an engineer and loving the lectures! So we’ll presented!

[@mssn3166]

He's a great teacher who explains very well

[@kabinehkpukumu6182]

This is a great lecture! Thanks MIT Opencourseware

[@Pradreamschasers]

Now I know the difference between MIT and MU.not the curriculum but the faculty.

[@minthuta726]

This is quality education of MIT, very useful.

[@alexisstoned7796]

Holy fuck MIT classes public. Awesome.

[@Toannguyen-hi3sf]

Thank you Mit and prifessor Gruber for the useful lesson 🥰

[@stevedavenport1202]

This professor is amazing. I wish mine were as good at explaining econ like him.

[@elkyelkyelky]

Finished, so appreciated of sharing, great instructer.

[@leopoldlee4698]

His voice is pretty young

[@aasemahsan]

*Assumptions* Completeness Transitivity Non-satiation 9:23 Four properties of indifference curves -Consumers prefer higher indifference curves -Indifference curves are downward slopping (Non-satiation) -Indifference curves never cross (Transivity) -Only one IC through every bundle 15:01 Utility functions Marginal utility 24:34 Marginal rate of substitution Indifference Curves are convex to the origin 32:38 Real life example of diminishing marginal utility 🔥

[@jayantasaud]

Great explanation. Liked it very much.

[@danieldelights1]

Great eye opening lecture.

[@parasbhanushali2400]

Well my economics Professor in Germany did an equally good job (albeit in German)... I'm watching this to correlate the terminology in English. He used the most German Example ever! Beer and Wine!😝🤣

[@owenfranklin944]

I like how his chalk will just snap in half and he'll just keep on going without batting an eye.

[@marcianojordy7719]

I dont know why I'm doing this to myself, but I am still in highschool and your boy here trying to learn some university materials, I feel very proud😂😂

[@lyoncristiano8783]

Estou adorando as aulas com este professor, thanks ;)

[@baldinib1055]

voce entende tudo?

[@wesleydomingos349]

@@baldinib1055 Eu particularmente não. Quando há algo que não entendo vou pro google tradutor. Você chegou a finalizar?

[@BlakeDee]

Thank you Prof Gruber.

[@Megaritz]

Slight correction on opioids: Very few people switched from Oxycontin to heroin of their own volition. To say they did so actually buys into an Oxycontin-->heroin gateway drug theory, which is very dubious, like most other gateway drug theories. Most people who switched from Oxycontin to heroin did so after their Oxycontin supply was cut off. The overdose rates would be lower-- still too high, but much lower than at present-- if we hadn't cut people off (whether pain patients, addicts, recreational users, or whatever combination thereof) off of their prescription opioids.

[@rohithbtr4192]

I am falling in love with this

[@MegaAlfonso1974]

EXCELENTE CLASE. gracias ¡¡¡¡

[@leobrsp]

thank you professor and MIT !

[@ReginaldRichard-zg4xp]

this lecture is realy good

[@allusionsxp2606]

I’m learning about this!

[@sidhivinayakdutta4091]

Wonderful lesson.

[@suindude8149]

It's the aggregate behaviour of indifference curve which show's the cross section of indifference curve.

[@ashokkuwar6845]

The best presentation.

[@danielfrt]

for the diminishing marginal utility function, the partial derivative with respect to cookies is = 1/(2*sqrt(p*c))*p, so the MUF with cookies=1 is 0.7, not 1.4. same result with the first derivative with constant p=2

[@zachsimon9475]

Ok you sound like a math guy, what happens to the Utility Function when you get hungry again, wouldn’t that affect your enjoyment or desire for another pizza or cookie? And how would that effect the formula

[@grolm8335]

@@zachsimon9475 listen to the question and his explanation at 40:06

[@andotech]

I noticed this, too, after calculating the partial derivative to get the MUF and wasn't sure if I was missing something or what ... I'm still not sure why he's not using the partial derivative of the UF to calculate the MUF.

[@samedy00]

In fact he uses not the exact derivatives, but the finite differences here. For the second cookie the utility function goes from 1.4 to 2, thus, the forward difference will be 2-1.4=0.6. And on margin utility slide he indeed has 0.59 for the second cookie. The same is true for the third one: 2.45-2=0.45, and so forth.

[@fran.sancisco]

on @31:31, even if it does make sense mathematically, once you gave one slice of pizza for one cookie, on the second trade, it does make sense to trade 2 slices of pizza for one cookie. I know this is theoretical, but it does not count the diabetes variable :P. that said, wonderful course!

[@xinggu1571]

Correction: 23:42 I don't think a negative sign could be attached to the formular for U. It would make the marginal unilities negative.

[@akeemibrahim8058]

Great lecture

[@hongyo122]

Professor thank you so much!

[@sena8500]

thank you so much this class really helped me

[@uisimedo]

Cigarette discussion was amazing !

[@hitbitVLOGGER]

This is so easy in comparison to what we study in india.

[@VuNguyen-io7pz]

Damn bro you so smart

[@marcogiorgini8566]

Opportunity cost of watching these videos is amazing

[@qin6409]

even non-economics students can understand his lecture, maybe this is what a good teacher is.

[@francescomanzo3939]

it is a class for engineering students after all

[@gtawalkthrough336]

For the last question, I think we are talking about different decision, scenarios which mean the indifference curve shift, so we cannot compare the marginal utility in this case

[@suindude8149]

We observe in the shift of indifference curve the MRS exists hence,MU will always be there.

[@arevaloneyra2283]

Question, does the MRS in an indifference curve indicate a preference within the indifference curve?

[@saeidhajhidari7072]

Today I am happy because to first time I find your page and I can learning science of the day because I am Iranian and here there aren't science of day . Tank you so much of MIT University to open course ware

[@vaibhavkeshari9620]

God bless you

[@mattk1124]

Wow really good prof

[@ndasi4158]

These lectures are fire 🔥 wish that was my professor

[@srinivasams9323]

Ging Freecss is the smartest character in anime. Lelouch is trash

[@charlesstpierre9502]

You can't know if the second movie will not so exceed your expectations as to make you happier. Your a priori assumptions may be incorrect. But it is impossible to know this- a priori. Use upward sloping curves when one is a cost for the other. The cost for three of something may be more than three. As when marginal utility declines, as minimal cost (of production) is still additive. Oh! "The cookie monster:" Alone on a dark street: The marginal utility of a cookie. He sighed, looking up. Something to think about.Thank you again, Professor Gruber. I found your course useful and fun. My idea if fun, of course. And- The pizza will get cold.

[@ghaithghazi6748]

This Guy is AWESOME!!

[@enteryourname4284]

Notes Demand Curve - How consumers make choices Supply curve - How firms make production decisions Constaint maximization Utility maximization - preference and budget constraints The demand decreases but the cost of production remains the same

[@9874763372]

FENTANYL is mostly produced in the Golden Triangle( consisting of areas in Myanmar, Laos and Thiland) not in China.

[@ashstewart4999]

Does that make the marginal rate of substitution the derivative of the marginal utility rate? Or does the gradient always have to be an average rate of change rather than the gradient of a tangent?

[@karumotoart5040]

I'm showing more class participation here than my actual class. I genuinely saying out the answers to his questions loud while my profs make me feel as if there's something wrong with coffee nowadays

[@frylock6403]

32:03 Bless you person who sneezed

[@berzerksharma]

I just understood the Mrs = ∆p/∆c = -MUc/MUp , with all the math i know, it's basically the slope in partial derivative form

[@gunaypnahova7094]

Thanks MR professor 👏🏼👏🏼👏🏼👏🏼🇦🇿🇦🇿🇦🇿Hello from Azerbaijan ❤️❤️❤️

[@kiranfhh9059]

GREAT VIDEOS

[@user-lg3iy4lp2q]

Great Video and for figure 2-5, y-axis should be dU/dC instead of Utility.

[@Andalusian_]

Good catch

[@barath.m8148]

as stated in the sense "next unit bring less joy than the previous held units" but what if the next unit is equal to whatever the initial amnt unit you are holding atm as in having x amnt of said stock instead of getting x+1 ;x+X amnt .technically its multiple singular units but will it affect the indifference graph when given coupled together ? (is this a rational question or am i missing something?)

[@tvvt005]

8:51 idk if this is a dumb question but why is it curved? Like package c ,, can it not be linear?

[@pelimaxxx]

Watching this kind of videos reminds me of Isaac Asimov saying decades ago the possibilities of learning with the invention of modern computers and internet. I’m on the subway in Latin America watching lectures of MIT, come on! 🤷🏼‍♂️

[@hawigebeyehu6554]

Thanks Prof

[@vedushikajayathilake4795]

Thank you sir !!

[@TheHenranMan]

watching this from UCSC, tryna cram for my midterm tomorrow

[@4dogsannacat]

If you derive $1's worth of utility dreaming about winning the lottery then that dollar is not wasted when you don't win.

[@domsjuk]

Reasonable. Next on: opportunity costs. :D

[@savitamalhotra9180]

I didn't get the 4th property of IC - that there is only one possible ic for every consumption bundle. Can someone help me out here.

[@Merione]

It's more or less the same as property #3: ICs don't cross, for the reasons he explains, thus you can't have more than one IC going through a single point. If there was more than one IC for a single point, then they would cross each other, and that's not allowed.

[@althafyoosuf7945]

Excellent 🌷

[@MrFatboyfun]

Law of Diminishing MU… can we take advantage of the firms based on this law? Example… L soda is 1.50, XL soda is 2.00 and is 2x as much. Consumers should purchase 1 XL and split it thereby saving 1 dollar. We see this happen a lot at the movie theater concession counter.

[@chirantansarkar8888]

Sir i don't know i am having ur previous lecture they are as good as these are.

[@ilyasb4792]

Can someone please answer this question ? We've seen that because of diminishing marginal utility, the demand curve shift less the more the quantity you want to buy. But since the spacing is less and less, and if we suppose we have an infinite demand, will it converge toward a fixed quantity ? My mathematical intuition tells me that's the case, but my economic intuition tells me that infinite demand needs infinite supply since not every agent in the economy will be at the same position in the utility function; for any number of agent there will be at least one that's going to buy it's first item and will want more, meaning that demand will increase.