#LyX 2.0 created this file. For more info see http://www.lyx.org/ \lyxformat 413 \begin_document \begin_header \textclass article \use_default_options true \maintain_unincluded_children false \language english \language_package default \inputencoding auto \fontencoding global \font_roman default \font_sans default \font_typewriter default \font_default_family default \use_non_tex_fonts false \font_sc false \font_osf false \font_sf_scale 100 \font_tt_scale 100 \graphics default \default_output_format default \output_sync 0 \bibtex_command default \index_command default \paperfontsize default \spacing single \use_hyperref false \papersize a4paper \use_geometry true \use_amsmath 1 \use_esint 1 \use_mhchem 1 \use_mathdots 1 \cite_engine basic \use_bibtopic false \use_indices false \paperorientation portrait \suppress_date false \use_refstyle 1 \index Index \shortcut idx \color #008000 \end_index \paperwidth 15cm \paperheight 24cm \leftmargin 2.5cm \topmargin 2.5cm \rightmargin 2.5cm \bottommargin 2.5cm \secnumdepth 3 \tocdepth 3 \paragraph_separation indent \paragraph_indentation default \quotes_language english \papercolumns 1 \papersides 1 \paperpagestyle default \tracking_changes false \output_changes false \html_math_output 0 \html_css_as_file 0 \html_be_strict false \end_header \begin_body \begin_layout Standard \paragraph_spacing onehalf \noindent \align center \family typewriter \size large Prof. Marek Weretka's \end_layout \begin_layout Standard \paragraph_spacing onehalf \noindent \align center \series bold \size large Econ 301 Intermediate Microeconomics \end_layout \begin_layout Standard \paragraph_spacing double \noindent \align center \series bold \size huge Problem Set 4 \end_layout \begin_layout Standard \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Subsubsection* \paragraph_spacing onehalf Problem 1 \end_layout \begin_layout Standard \paragraph_spacing onehalf As in the previous problem set, Benjamin spends his time either watching movies \begin_inset Formula $(x_{1})$ \end_inset (as you know he is taking advantage of "on demand" option, cable TV) or listening to the songs - MP3 downloaded from the Internet \begin_inset Formula $(x_{2})$ \end_inset . His preferences are \end_layout \begin_layout Standard \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Standard \paragraph_spacing onehalf \begin_inset Formula $U(x_{1},x_{2})=4ln(x_{1})+ln(x_{2})$ \end_inset . \end_layout \begin_layout Standard \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Standard \paragraph_spacing onehalf His total income is \begin_inset Formula $m=100$ \end_inset , the price of MP3 is one dollar per each song ( \begin_inset Formula $p_{2}=1$ \end_inset ). Suppose that the price of a movie drops from \begin_inset Formula $p_{1}=10$ \end_inset to \begin_inset Formula $p_{1}=5$ \end_inset . \end_layout \begin_layout Standard \paragraph_spacing onehalf a) By how much the "consumption" of movies changes due to the price drop? \end_layout \begin_layout Standard \paragraph_spacing onehalf b) Are movies ordinary or Giffen goods? Explain why. \end_layout \begin_layout Standard \paragraph_spacing onehalf c) By how much \family roman \series medium \shape up \size normal \emph off \bar no \strikeout off \uuline off \uwave off \noun off \color none \begin_inset Formula $x_{1}$ \end_inset \family default \series default \shape default \size default \emph default \bar default \strikeout default \uuline default \uwave default \noun default \color inherit changes because movies are cheaper relative to MP3 (find substitution effect) \end_layout \begin_layout Standard d) How about the effect of increased purchasing power of Benjamin's income? (find income effect) \end_layout \begin_layout Standard \paragraph_spacing onehalf e) Is the income effect in d) positive or negative? Why? (Hint: is a movie a normal of inferior good?) \end_layout \begin_layout Standard \paragraph_spacing onehalf f) Show the total change, the substitution and income effects on the graph. \end_layout \begin_layout Standard \paragraph_spacing onehalf \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Subsubsection* \paragraph_spacing onehalf Problem 2 \end_layout \begin_layout Standard \paragraph_spacing onehalf Consider Trevor from our previous problem set. He begins the day with a strawberry milkshake (milk and strawberries mixed in proportion 1:5). His income is equal to m=200 , and one strawberry costs \begin_inset Formula $p_{2}=1$ \end_inset . Suppose the price of milk drops from \begin_inset Formula $p_{1}=15$ \end_inset to \begin_inset Formula $p_{1}=5$ \end_inset . \end_layout \begin_layout Standard \paragraph_spacing onehalf a) What is the total change in demand for milk. \end_layout \begin_layout Standard \paragraph_spacing onehalf b) What is a substitution effect \end_layout \begin_layout Standard \paragraph_spacing onehalf c) How about income effect \end_layout \begin_layout Standard \paragraph_spacing onehalf \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Subsubsection* \paragraph_spacing onehalf Problem 3 \end_layout \begin_layout Standard \paragraph_spacing onehalf Miriam has quasilinear preferences over consumption of coffee \begin_inset Formula $(x_{1})$ \end_inset and muffins \begin_inset Formula $(x_{2})$ \end_inset given by \begin_inset Formula $U(x_{1},x_{2})=5ln(x_{1})+x_{2}$ \end_inset . Her income is equal to \begin_inset Formula $m=$ \end_inset $10, and \begin_inset Formula $p_{2}=$ \end_inset $1. \end_layout \begin_layout Standard \paragraph_spacing onehalf a) Find MRS as a function of consumptions of two commodities. Write down two secrects of happiness. \end_layout \begin_layout Standard \paragraph_spacing onehalf b) Find optimal consumption of \begin_inset Formula $x_{1}$ \end_inset and \begin_inset Formula $x_{2}$ \end_inset for arbitrary value of \begin_inset Formula $p_{1},p_{2},m$ \end_inset using two secrets of happiness from a) (assume interior solution) \end_layout \begin_layout Standard \paragraph_spacing onehalf c) Suppose price of coffee drops from \begin_inset Formula $p_{1}=$ \end_inset $5 to \begin_inset Formula $p_{1}=$ \end_inset $1. Find substitution effect. \end_layout \begin_layout Standard \paragraph_spacing onehalf d) Find income effect \end_layout \begin_layout Standard \paragraph_spacing onehalf \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Subsubsection* \paragraph_spacing onehalf Problem 4 \end_layout \begin_layout Standard \paragraph_spacing onehalf Dave is initially endowed with 20 apples and 20 oranges \begin_inset Formula $ω=(20,20)$ \end_inset \end_layout \begin_layout Standard \paragraph_spacing onehalf a) Assume \begin_inset Formula $p_{1}=p_{2}=2$ \end_inset . Write down Dave's budget constraint, and plot budget constraint in the graph. Mark all bundles on budget line for which Dave is selling apples and is buying oranges. \end_layout \begin_layout Standard \paragraph_spacing onehalf b) Suppose \begin_inset Formula $U(x_{1},x_{2})=x_{1}x_{2}$ \end_inset . Find indifference curve that passes though endowment point analytically and find its slope (MRS) at the endowment point. Depict the curve and the slope in the graph. \end_layout \begin_layout Standard \paragraph_spacing onehalf c) Assume \begin_inset Formula $p_{2}=2$ \end_inset and find optimal choices of Dave under three scenarios: \begin_inset Formula $p_{1}=1,p_{1}=$ \end_inset 2 and \begin_inset Formula $p_{1}=3$ \end_inset . Determine net demands of Dave for apples and oranges. \end_layout \begin_layout Standard \paragraph_spacing onehalf d) Is Dave buying or selling apples on the market under the three scenarios? Explain why he is using such trading strategy by comparing MRS at the endowment point with relative price. \end_layout \begin_layout Standard \paragraph_spacing onehalf e) Connect the three optimal bundles to obtain price offer curve and plot it on a graph with indifference curve passing though endowment point. Is your price offer curve located above the indifference curve? \end_layout \begin_layout Standard \paragraph_spacing onehalf \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Subsubsection* \paragraph_spacing onehalf Problem 5 \end_layout \begin_layout Standard \paragraph_spacing onehalf Kate is not sure how many hours she should spend at work and we have to help her. Her total available time is 24h. She has no other source of income but salary. She is a lawyer, and a current wage rate for lawyers (per hour) is \begin_inset Formula $w=$ \end_inset $100. She only consumes bananas that cost \begin_inset Formula $p_{c}=$ \end_inset $5 per pound. \end_layout \begin_layout Standard \paragraph_spacing onehalf a) What is her real wage rate (wage rate in terms of bananas) ? \end_layout \begin_layout Standard \paragraph_spacing onehalf b) Show her budget set on the graph. \end_layout \begin_layout Standard \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Standard Suppose her utility function is : \end_layout \begin_layout Standard \paragraph_spacing onehalf \align center \begin_inset Formula $U(C,R)=R×C$ \end_inset \end_layout \begin_layout Standard \paragraph_spacing onehalf where R is leisure (or relaxation time) and C is consumption of bananas. \end_layout \begin_layout Standard \begin_inset Formula $\vphantom{}$ \end_inset \end_layout \begin_layout Standard \paragraph_spacing onehalf c) Find her optimal time spent at work, the relaxation time and consumption of bananas. \end_layout \begin_layout Standard \paragraph_spacing onehalf d) How your answer in c) would change if her wage rate was \begin_inset Formula $w=$ \end_inset $ \begin_inset Formula $200$ \end_inset . How would you explain the change (or possibly no change) in her labor supply? \end_layout \end_body \end_document