Wednesday, May 20, 2009
Answers/Hints/Solutions DSE 2004-2008: Macroeconomics
Answers/Solutions/Hints for DSE 2004-2008: Mathematics/Statistics Part
Utmost care has been taken to provide correct solutions but there can be mistakes so use this document AYOR. In case of mistakes kindly mail us at ecopoint.dse@gmail.com
DSE 2004 Mathematics/Statistics
ECOPOINT : MA Economics 2009 Entrance Coaching by DSE Alumni. 9999886629, 9873903314, 9899048237
Ans 1 (b) only proposition (i) is true (prove using contradiction: if possible $ x Î BÇC, then x Î B and x Î CÞ ? )
Ans 2 (b) there exists a solar system in the milky way galaxy such that every planet in it has a moon revolving around it without any life forms.[negate the given statement]
Ans 26. (c) 2/3 [use baye’s theorem] Ans 27. (d) 3/32 Ans 28. (a) 2/3 Ans 29. (c ) 7.4
Ans 30. (d) 2p2
Part 2
Ans 2 A (a) np(1-p)(pn-2 + (1-p)n-2)
A (b) [1-np(1-p) (pn-2 + (1-p)n-2)]k-1 [np(1-p) (pn-2 + (1-p)n-2)]
Ans 2 B (a) a=1/48 [ use property of a pdf]
B (b) prob(3 <X <5) = 7/24 [ use 3ò5 a(x-3)dx ]
B (c ) prob (X³ 4) = ¾
DSE 2005 Mathematics/Statistics
ECOPOINT : MA Economics 2009 Entrance Coaching by DSE Alumni. 9999886629, 9873903314, 9899048237
Ans 5 (b) a tribe Ans 6 (d) a tribe
Ans 7 (b) there are atleast two sets of individuals that are both a Club and a Tribe
Ans 8 (a) a club
Ans 13 (d) every book by Bourbaki contains a chapter such that the validity of all the theorems in it is independent of the reader’s gender. [ negate the statement]
Ans 16 (a) P(E È F) = P ( Number of Heads > number of Tails or number of Tails > number of Heads) = 5/8
Ans 17 (b) 2/9 Ans 18 (b) ½ Ans 19 (c) 2p2 Ans 20 Do yourself
Ans 21 (b) [ i=1Sn (c-xi ) - =1Sn (cyi - xi )]/ c Ans 22 (c) 48/65 Ans 23 (c) 3
Part 2
Ans 1 A (a) required variance= 25/49 + 36/49 = 61/49
Ans 1 A (b) required variance= 50
Ans 1 A (c) Null hypothesis H0 : mA - mB =0
Z= [mean(XA) – mean(XB)] / Ö [25/36 + 36/49] = -25/1.2 ~ -20
Null hypothesis H0 is rejected
Ans 1 B (a) True
Ans 1 B (b) True
Ans 1 B (c) False
Ans 1 B (d) False
Ans 1 B (e) True
Ans 4 A Homogenous functions; Euler’s theorem.. prove!!!
Ans 4 B (a) a33 ¹ -3
Ans 4 B (b) Price = 61/6
DSE 2006 Mathematics/Statistics
ECOPOINT : MA Economics 2009 Entrance Coaching by DSE Alumni. 9999886629, 9873903314, 9899048237
Ans 9 (d) 3/8 Ans 12 Do yourself Ans 14 (d) any of the above three conditions is satisfied
Ans 15 (c) f is quasi convex Ans 16 (b) changes the sign of the determinant
Ans 17 should be 1/25 [ 5(1/5x 1/5x 1/5) = 5/125 =1/25 ] Ans 18 (d) 0.82
Ans 27 (c) Rs. 4000 Ans 28 (b) 0.56
Ans 31 (a) 5/14 Ans 32 (d) 2/7 Ans 33 (b) 0 Ans 34 (b) 128
Ans 37 (c) the line defined by y=x+2 and the vertical axis
Ans 46 (d) 7/15 Ans 47 (b) 121/256 Ans 48 (c) 4/13 Ans 49 (a) 28/30
Ans 52 (c) is greater than or equal to 0 at every xÎ Â
Ans 53 (d) in every election, every party has atleast one dishonest candidate. [ negate the statement]
Ans 54 (b) a gang Ans 54 (d) a gang
Ans 56 (b) there are atleast two sets of individuals that are both a family and a gang
Ans 57 (a) a family
Ans 58 (a) 45 Ans 59 (b) 3/8 Ans 60 (d) f(x) =|x| where xÎÂ and x ³0
DSE 2007 Mathematics/Statistics
ECOPOINT : MA Economics 2009 Entrance Coaching by DSE Alumni. 9999886629, 9873903314, 9899048237
Ans 11 (a) f(x) = x2
Ans 12 (c) det A = det B [ by operations on determinant]
Ans 13 (b) Df(x)=0 for some xÎ Â
Ans 14 (d) in every legislature and every party, there exists a legislature who doesnot pay taxes
Ans 15 (c) singular Ans 16 Do yourself Ans 17 (c) increases steadily from 0 to 1
Ans 18 (d) 4/7 Ans 19 (b) (i)28/30 (ii) 0.29 Ans 20 (c) 7.5 Ans 23 (a) (i) 1 km and (ii) Rs. 100
Ans 41 (a) { (x,r) Ân X Â| f(x)£ r } is convex Ans 42 (a) 2xe(x2) - ex
Ans 43 (d) converges neither to 1 nor to -1 Ans 44 (d) [-1,1] Ans 45 (c) (-1,1) Ans 46 (d) d(x,z) £ d(x,y) + d(y,z) Ans 47 (b) (A-B) X C = (AXC) – (BXC) Ans 48 (c) attains a saddle point
Ans 49 (c) 4.5 Ans 50 (d) during warm weather, my crops suffer from pests more than during cooler weather. Therefore, a warm environment must help pests to multiply.
Ans 51 (d) None of the above Ans 52 (3!3!)/6! (option not available) Ans 53 (b) 5/18
Ans 54 (b) (1/2, 3/4, 1/2) Ans 55 (b) 37.6 years Ans 56 (a) 0.025 Ans 57 (d) 5, 0.5, 39
Ans 58 (d) 0.79
Ans 59 (b) there is a significant difference in the performance of the classes at the 5% level but no significant difference at 1% level of significance
Ans 60 (b) there is no significant difference between the districts and the candidate is preferred in district A.
DSE 2008 Mathematics/Statistics
ECOPOINT : MA Economics 2009 Entrance Coaching by DSE Alumni. 9999886629, 9873903314, 9899048237
Ans 1 Do yourself Ans 2 (a) Ans 3 (d)
Ans 4 (c) III and IV [ consider any example based on the respective definitions of mutually exclusive sets and independent sets ]
Ans 5 (a) g(y) = f(Öy) " y= 1,4…..400 and g(y) = 0 otherwise
Ans 16 (a) both functions are linear
Ans 17 (b) -(yxy-1 + zx ln z)/ (xzx-1 + yz ln y) [ partially derivate, revise differentiation!! ]
Ans 18 (c) constant [ this is simple!!!] Ans 19 (a) will change the sign of det A (true for all nxn matrices ) Ans 20 (b) 3 ( think logically ) Ans 21 (b) Ans 22 (c) Ans 23 (a) Ans 24 (c) Ans 25 (c)
Ans 26 Do yourself Ans 27 Do yourself Ans 28 (d) Ans 29 (b) Ans 30 (c)
Ans 51 (d) the rows of A are linearly independent Ans 52 (a) strictly convex Ans 53 (c) exactly one solution Ans 54 (b) if player 1 plays appropriately, she can win regardless of how 2 actually plays
Ans 55 (a) Ans 56 do yourself!! Ans 57 (b) a set having a single point Ans 58 (a) ep
Ans 59 (c) is discontinuous at x=0 Ans 60 (c) linearly dependent
Tuesday, May 19, 2009
Microeconomics 2008 paper: Answers/Hints/Solutions to Past year paper/Exam of Delhi School Of Economics (DSE)
Microeconomics 2008
Ans 6. (b) U(x,y) = 10{x2+4xy+4y2}=10{x+2y}2 +20
Ans 7. U = min{x+y,2y} Because x=y=3, so consumer chooses on x+y so Px=Py(Think about the missing links here)
Ans 8 (c ) Ans 9 (d) Ans 10 (d) Apply the formula of elasticity of subsitution
Ans 31 (a) (Whole box would be PE. Is it?)
Ans 32 (d) Ans 33 (b) Ans 34 (c) Ans 35 (c)
Ans 36. (a) xR*y, yR*z,zR*x. Cyclical Preferences so WARP is violated
Ans 37 (c ) Derive k=5/1+(5-e)2 and e=(10/F)1/2
Ans 38 (d) Derive 2k2e+2eF2=10k2 or e=5k2/F2+k2
Ans 39 (c ) Derive dπ/de=2k2(5-e)-t=0 or t=10k2+F2/k2+F2
Ans 40 Do yourself
Microeconomics 2007 Paper: Answers/Hints/Solutions to past year papers/Exam of Delhi School of Economics (DSE)
This is the fourth series of solutions for Microeconomics questions asked in DSE Past years papers
Microeconomics 2007
Ans 1. (c) {20,0}
Ans 2. (a) a vertical line
Ans 3 (b) K=3/2L
Ans 4. (c) MR < 0 in such a case.(Apply the formula, MR=P(1+1/ed) )
Ans 5 (a) A,B (Applying WARP)
Ans 8 (a) always reduce borrowing
Ans 21 (c) 1200-488L+72L2 -4L3
Ans 22 (d) (i) Rs 4,80,000 (Apply πox+(1-π)oy) and (ii) risk loving
Ans 23 (a) (i) 1km and (ii) Rs 100
Ans 24 (a) some firms will exit the industry but other will remain (At P=ATC, Supply > Demand, so?)
Ans 25 (b) 9 Apples
Ans 26 (a) 3.5 kg (SE = 33.5-30=3.5)
Ans 27 (d) ((0,0),( 8^1/2,2),(3-8^1/2,1)) (After maximization exercise, y1=x1/2^1/2,so?)
Ans 28 (c) Pareto efficient because there is a bound on Agent’s 1 ability to consume
Ans 29 (b) 2^1/2 (Hint : a=2y1/x1)
Ans 30. (b) ((0,0),( 3-48^1/2/5, 3-12^1/2/5), ( 48^1/2/5, 12^1/2/5))
Ans 37 (c) (1+δ)w2>(1+r)w1
Ans 38 (a) goes up
Microeconomics 2006 Paper: Answers/Hints/Solutions to Past year Papers/Exam of Delhi School of Economics (DSE)
This is the third series in solutions to Microeconomics problems asked in DSE Past years papers
Microeconomics 2006
Ans 1 (b) Pareto efficient. Since both prefer more to less, if you take any chocolates from A and give it to B, then you would make B better off and A worse off, so PE.
Ans 2 (d) all of the above
Ans 3 (b) a private good
Ans 4 (b) Monopsony
Ans 5 (d) C = Q(wr)^1/2
Ans 10 (d) Do yourself
Ans 11 (b) Quasilinear Utility function. (Income elasticity of good x is zero)
Ans 13 (c) remains constant. ( Think what will happen if you have CRS and IRS)
Ans 21. (b) Not a competitive equilibrium allocation but is Pareto efficient. (x1,y1) =(3,3) & (x2,y2)= (7,2). Here PE allocations would be a band of PE Allocations. Find demand functions of agent 1 and 2, for both goods, you will get an equation, where what value you should keep for p1 to equate demand and supply
Ans 22. (a) A competitive equilibrium allocation and is Pareto efficient. (x1,y1) =(10,5) & (x2,y2)= (0,0).
Ans 23 (b) {p1,p2} = {0,1}
Ans 29 (b) {q1,q2}={2,2} (MR1=MC, MR2=MC}
Ans 30 (b) A has x=2,y=0 and B has x=0 and y=2 (Generally, where does PE Allocation of max{x,y} lies? What if you have max{x,2y} or max{2x,y}?)
Ans 40 (b) {x,y} = {2/18,5/18}
Ans 41 (c) x1 increases and x2 decreases
Microeconomics 2005 Paper: Answers/Hints/Solutions to Past Years Papers/Exam of Delhi School of Economics (DSE)
This is the second series of Microeconomics Questions asked in DSE
Microeconomics 2005
Ans 1 (d) (x1,y1) =(100,100) & (x2,y2)= (50,0) (Think, can this be a case of multiple competitive equilibrium?) (Here first two could be easily eliminated, but what about (c ) )
Ans 2 (a) (x1,y1) =(50,50) & (x2,y2)= (100,50) (What would be the pareto efficient points, will it be a diagonal line, a line from lower left origin to {100,100} point, or the portion of horizontal part of upper axis. Think!)
Ans 3 ( c) (Think why not b)
Ans 4 (b) (x1,y1) =(50,50) & (x2,y2)= (100,50) (Find out demand functions of agent 1 and 2, for both goods. D1 = {50,50}, D2: x2 Є {0,100}, y2 Є {0,100})
Ans 9 (a) {q1,q2} = {a/3b,a-3/3b}
Ans 10.(a) The market share of more efficient firm increases
Ans 11 (c ) q1 will increase and q2 will decrease. (What is this kind of market model called? {q1,q2} = {(a-ab-2b-1)/2b2, (3ab-2b-a+1)/4b2} )
Ans 12. (d) Produce nothing in Plant 2
Microeconomics 2004 Paper: Answers/Hints/solutions to Past Year Papers/Exam of Delhi School of Economics (DSE)
Here I am giving indicative solutions for DSE Papers. I am giving hints and some thought points to ponder over. All mistakes are mine, kindly mail me wherever you find mistakes at ecopoint.dse@gmail.com First I am posting for Micro and in subsequent posts would do for Macro and Maths
Microeconomics 2004
Ans 3.(c) x1=y1 for x1 Є {0,1000} (The set of allocations would be on the diagonal line (Think, what if the Edgeworth box is not a square)
Ans 4. (c) x1=y1 for x1 Є {0,1000} (It is a case of multiple equilibria. Solve for demand functions of i, j (Think, does min-min always give multiple equilibria)
Ans 5 (d) Both are pareto efficient. For both α and β, check by transferring the resources, can you make one person better off and other person worse off. In this case both α and β are pareto efficient.(Remember it is not a square now)
Ans 6 (b) (Again a case of multiple equilibria)
Ans 7. (a) Competitive Equilibrium prices (1,0) .(Think, a good in excess supply is x2. Is this the case always?)
Ans 8. (c ) {q1,q2} = {3-4c/6,c/3}; {s1,s2} = {3-4c/3-2c,2c/3-2c}
Ans 9 (b) No, collusion could be Pareto efficient
Ans 10. (a) ½
Ans 11. (d) Produce nothing in Plant 1
Ans 12. (c ) p=1-q π=(1-q)q-1/2q Find dπ/dq, q=1/4
Ans 13. (a) Use Slutsky SE, {x0,y0} = {5,5/3}, {x1,y1} = {5/2,5/3}, (x1-x0,y1-y0} = {-5/2,0}
Ans14 (d) (200)1/2 -10.Use Hicksian SE, keeping the original utility constant
Ans 15 (b) At U=25/3. Calculate m =(200)1/2. {x1,y1} = {(200)1/2 /4, (200)1/2/6} Δ = {5/2-(200)1/2 /4, 5/3-(200)1/2/6} =(10-(200)1/2 )/4, (10-(200)1/2)/6
Ans 16. (a) Deficit decreases by 15-(200)1/2
Ans 17 (d) removing the water subsidy and providing lumpsum subsidy
Tuesday, April 28, 2009
Analysis of ISI Paper 2004.
We are the group of DSE Alumni, giving coaching for MA Economics Entrance for DSE, ISI and JNU. Here in series of posts to follow, we would be analyzing the past exams. These are only indicative hints, not even solutions to the questions. For further clarifications you can call us at the numbers mentioned below.
Here, we would discuss in brief what has been asked in ISI Past years' papers. I am only analyzing 'Economics' part of the paper right now, for 'Mathematics' part, discussion would be done later on taking all the years together.For some questions I would write "dont dare to ask", since they would be very very easy to solve.
Before the analysis, some piece of advice.
Good thing about ISI is, that they never ask you anything beyond what they have defined as their syllabus. The level of questions is higher no doubt, but doable.
My advice to all the aspirants is, please dont loose hope. If you, while doing the paper, are not able to solve something, some concept goes out of the mind, then even dont panic and do something. They want to know your line of thinking, your economic intution.
Dont sit with an attitude that this paper is bigger than life !
Just sit for complete time there, apply your mind, forget about the results, beware of the games which mind plays with you, just crack the paper there itself, with full concentration,
Write whatever comes to your mind as a logical solution to a problem, dont give up at all.
ISI professors (Gods), want to judge your mental stamina, how much you can think. Believe me all of you, have a chance to win, just dont give up before the bell rings..
ISI 2004-Economics Part (http://www.isical.ac.in/~deanweb/syllsqmsqe2k4(mod).pdf) Copy it
Ques 1. Part 1. Very simple. Find out optimal bundle in Perfect subsitutes and apply formula for own price elasticity.
Part 2. Form two equations and find out x
Part 3. Production function in min form then cost function would be in Perfect subsitutes form
Part 4. Dont dare to ask !!
Part 5. Derivate the C + I + G =Y equation and get the solution
Part 6. XII Class level question
Ques 2. Part 1 & 2, Dont dare to ask
Part 3. Apply the definition of homethetic prefernces in all kinds of utility functions and then see
Ques 3. One of the firm will go out of market because of incidence of fixed cost. Find out
Ques 4. Simple Macro
Ques 5. Part 1. Budget line: Xe^2 + Xo = 2(I-R)
Part 2. {Xe,Xo} = {1,1/2}
Part 3. I - 1/2 -Xo
Ques 6. Even if income incraeses then consumption will not incraese after a certain point. Why?
Ques 7. They have told you what Laffer curve is and how it is drawn. Just use Implicit Function, to solve this
You can call us for further clarifications. All the best !!
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