Homework 7
Total Points: 10
Due date: October 30, 2015, 10:00 PM EST
1.
(5 points) Does the following project have a positive or negative rate of return? Show how
this is known to be true.
Investment Cost
$3,500
Net Benefits
$275 in Year 1, increasing by
Fixing Misbehaving Models
Bruce A. McCarl
Specialist in Applied Optimization
Distinguished Professor of Agricultural Economics,
Texas A&M University
Principal, McCarl and Associates
mccarl@tamu.edu
brucemccarl@gmail.com
http:/agecon2.tamu.edu/people/facul
1.
A local pig farmer wishes to know whether to expand his operation or
not. His pigs require a mixed diet which must have at least the
following nutrients: Protein  10%, Calories  30%, Iron  5%. The pigs
may be kept in one of three types of systems. T
AGEC 641  HOMEWORK
Chapter 13
Price Endogenous Programming
1.
Suppose the demand and supply for a commodity in each of the next
three time periods is given by
Period 1
Demand: P(1) = 1000  4y(1)
Supply: P(1) = 200 + 2x(1)
Period 2
Demand: P(2) = 1200 
Age Ec 641, Spring 2015
Chapter XI, XII
Homework
1.
Take the simple goal program
Max
3 X
4 X
X
X
a)
b)
2.
1
1
1
1
+ 3X
+ X
+ X
1
2
2
2
,
X
2
0
Develop a weighted tradeoff type objective function without targets.
Assume some targets and make it lexic
Age Ec 641, Spring 2015
Chapter XI, XII
Homework
1.
Take the simple goal program
Max
3 X
4 X
X
X
a)
b)
2.
1
1
1
1
+ 3X
+ X
+ X
1
2
2
2
,
X
2
0
Develop a weighted tradeoff type objective function without targets.
Assume some targets and make it lexic
Agec 641 Chapters 8 and 9 Homework
Fall 2015
1.
Suppose farmer Jones has livestock, wheat, and alfalfa. Livestock are kept for up
to 3 years, alfalfa up to 4 years, and wheat 1 year. The technical data are:
Characteristics by Year
Alfalfa
Wheat
1
3
4
0
20
Chapter VII Homework, 2015
1.
Charles Chicken manufactures chicken products. He has an integrated operation which
raises, processes and packages chicken for distribution. His operation is broken into 3
parts. Under chicken raising he has the following sit
AGEC 641
Chapter 5 Homework Group Effort
1.
John has a small factory in which he makes three types of furniture  fine, fancy and
super. John seeks to determine the amount of each type he should make so as to
maximize net returns.
The scarce resources Joh
Homework Chapter III IV
1.
Rancher Bob has a small farm on which he grows three types of crops: corn, hay
and cattle. The farmer seeks to determine the amount of each enterprise he should
grow so as to maximize net returns.
The scarce resources Joe must
More Linear Programming Models
The Assembly Problem  Primal Algebra
Max
c X
j
j

j
a
kj

j
ij
k
k
k
Xj
e X
d Q
j
j
w k Qk
f
ik
Qk
hk
for all k
bi
for all i
gj
0
for all j
for all k,j
k
Xj
Xj,
Qk
Objective:
Maximize the return summed over all the final
Lecture 11 Solving Nonlinear
Programming Problems
Zidong Mark Wang
2015 Fall
Based on material written by Gillig and McCarl; Improved upon by many
previous lab instructors; Special thanks to Pei Huang.
Introduction
We often encounter problems that canno
Homework 6
Total Points: 10
Due date: October 22, 2015, 10:00 PM EST
1.
(5 points) A company purchased some equipment at a very favorable price of $35,000. The
equipment resulted in an annual net saving of $2000 per year during the 8 years it was used.
At
Lecture 3 Inspection and Error
Messages
Zidong Mark Wang
2015 Fall
Based on material written by Gillig and McCarl; Improved upon by many
previous lab instructors; Special thanks to Pei Huang.
Model Inspection
When one has a big complicated data set
conta
Lecture 6 Conditionals, Subsets
and Tuples in GAMS
Zidong Mark Wang
2015 Fall
Based on material written by Gillig and McCarl; Improved upon by many
previous lab instructors; Special thanks to Pei Huang.
What is conditional ?
We often wish to have terms p
Lecture 2 General Problem
Zidong Mark Wang
2015 Fall
Based on material written by Gillig and McCarl; Improved upon by many
previous lab instructors; Special thanks to Pei Huang.
Review the simple model
1. Variable specifications
2. Equation specification
Lab Section for AGEC 641
Zidong Mark Wang
2015 Fall
Based on material written by Gillig and McCarl; Improved upon by many
previous lab instructors; Special thanks to Pei Huang.
Info
Connecting lecture materials with programming practices
1012 sessions
Lecture 7 GAMS Check
Zidong Mark Wang
2015 Fall
Based on material written by Gillig and McCarl; Improved upon by many
previous lab instructors; Special thanks to Pei Huang.
An aside: project file
*.gpr file: the GAMS project file.
The project location d
Lecture 4 Power of GAMS
Zidong Mark Wang
2015 Fall
Based on material written by Gillig and McCarl; Improved upon by many
previous lab instructors; Special thanks to Pei Huang.
WHY do we use GAMS
WHY do we use GAMS even though it is more complex than
some
Lecture 5 Good modeling
Zidong Mark Wang
2015 Fall
Based on material written by Gillig and McCarl; Improved upon by many
previous lab instructors; Special thanks to Pei Huang.
Why bother ?
How easy is it to reuse or modify a model at a later time for
you
Lecture 8 Exam model flaws
Zidong Mark Wang
2015 Fall
Based on material written by Gillig and McCarl; Improved upon by
many previous lab instructors; Special thanks to Pei Huang.
Unbounded Problems
1
Add large bounds to all variables which improve the ob
Hands On 6
Instructions:
Save HandsOn4a.gms as HandsOn6.gms and do a comparative analysis on a number of
price scenarios (using the BIG model without parameter changes): Using a loop statement
to run 11 scenarios (base will be the original price) on the f
Dynamic Linear Programming
Disequilibrium Known Life
Primal Algebra:
M ax
(1 r) t C jt X j, t
t
s.t.
(1 r) T
j
F I
je je
j
A
j eK j
ije
e
eK j
X j, t e
X j, e
X j, T e
X j, t ,
I je
I je
b it
X* e
j,
0
0
Where
(t + e)
C jt = (1 + r )
h je
e
where
Nonlinearities and Approximations
Minimization of the Sum of Absolute Deviations
1.
Y X b
i
i
ji
j
j
2.
A LP constraint set is formed by moving the
Xjibj term to the left side
of the equation.
i X ji b j Yi
j
3.
The basic problem of minimizing the summe
Modeling Summary
Types of Constraints
Resource Limitations
Minimum Requirements
Supply and Demand Balance
Ratio Control
Bounds
Accounting Relations
Deviation Constraints
Approximation or Convexity Constraints
Modeling Summary
Types of Variables
Production
1
Chapter VII Homework
1.
Consolidated Meat Packers buys cattle, hogs and chickens. After slaughter, the resultant
cuts of meat are sold directly or combined into hot dog, sausage, or dog food mixes. The
meat packer sells hot dog mix, sausage, dog food, c
Homework Chapter III
1.
Joe has a small factory in which he makes three types of meat products: sausage,
hot dogs and bologna. Joe seeks to determine the amount of each product he
should make so as to maximize net returns.
The scarce resources Joe must al
MIDTERM EXAM
AGEC 641
March 22, 1994
Answer 6 of the first 7 questions. Take the other question home along with
question #8 and turn them in on Wednesday by 5:00 p.m.
1.
Suppose we have a storage model of the following form:
Max
c1g1
c2g2
g1
h12s12
where
AGEC 641 Final Exam
Spring 1999
1. (15 points) Model the machinery selection part of the following situation in general:
A farmer wishes to buy a planter and a harvester. He must buy one of each. The planter
comes in either a 4 or 6 or 12 row configuratio