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标题: 2009 exam roll return question [打印本页]

作者: PalacioHill    时间: 2013-4-19 18:17     标题: 2009 exam roll return question

For Question 8Aiii, the answer states that the increase in convenience yield has the effect of increasing the roll return.  Looking at thismathemetically makes sense: F = Se^(rfr + cost - conv yield)T, so as conv yield goes up, the exponent goes down, and F goes down, making F
However, if you look at this intuitively I think you get a different result.  Roll return is defined (Schweser Book 4 Page 29) as the change in futures price not explained by change in spot price (F-S).  So if convenience yield goes up and forces F down, then F is a smaller number, making F-S a smaller number, and thereby decreasing the roll return.
Am I thinking of this the wrong way?
作者: Wasteoftime    时间: 2013-4-19 18:23

any thoguhts?
作者: WarrenB1    时间: 2013-4-19 18:25

I think you are looking at it just from the point of view of convenience yield which is wrong.
Interest rates will rise - so rf will rise
Convenience yield will drop - do - y will drop
what will be the combined effect - unknown - since you do not know the exact magnitude of each change.
作者: johnnyBuz    时间: 2013-4-19 18:27

cpk,
i understand that there are 2 differing effects that go in opposite directions and thats why the total effect is unkown/unchanged.
in my question, i was only focusing on the part of the answer dealing with the convenience yield, and trying to understand why the convenience yield increase causes backwardation and a roll return.
so the point in my last post was that the increased convenience yield causes F to be smaller, and since roll return is delta F - delta S, it becomes larger since F has to change more and more each period with a steeper  negative term structure.
作者: Valores    时间: 2013-4-19 18:28

hoping to bump this in case anyone has since looked at the 2009 exam.  just trying to fully understand why increase in convenience yield increases roll return, if we consider that roll return is the change in Futures price - change in spot price.
my guess is that since convenience yield decreases the numerator in the futures formula, F decreases.  this causes a more negatively steep term structure.  since F converges to S over time, each period the delta F is larger as it has to “clumb higher” to reach the spot price, thus increasing the roll return.
does this make sense?
作者: bigredhockey55    时间: 2013-4-19 18:30

pg 52 in v5 text
bottom of page states “all else being equal, an increase in a commodity’s convenience yield should lead to futures market conditions offering higher roll returns.”
作者: cross-ied    时间: 2013-4-19 18:32

Ok yea so what I wrote is correct.  Above that it says “The positive return is earned because as the futures contract gets closer to maturity its price msut converge to that of the spot price of the commodity.  Because in backwardation the spot price is greater than the futures price, the futurs price must increase in value.
Thanks.
作者: noel    时间: 2013-4-19 18:34

^good point
作者: hariRaj    时间: 2013-4-19 18:36

you are correct , show NY




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