1. 23 E-commerce 8
Aaron Schiff
ECON

2. Introduction
Objectives of this lecture: Understand “versioning” of information goods and how different versions can be created, how versioning can increase profits, and the factors that firms must consider when designing different versions.

3. Versioning
Information goods are often sold in different versions with different quality levels or other characteristics.
Examples:
256k DRM-free versus 128k+DRM songs on iTunes.
Windows Vista Home, Pro, Ultimate, etc.
Flickr free versus paid accounts.
Google Apps Standard vs Premier editions.

4. Example: Windows Vista

5. Example: Google Apps

6. Ways to Create Versions
Quality
128k vs 256k music files
HD vs standard video
Delay
Movie theatres first, DVD later
Amazon shipping
Live vs delayed stock quotes
User interface
Advanced vs basic search

7. Ways to Create Versions
Authorised uses
Restricted by DRM vs unrestricted
Capacity
Pro accounts on Flickr
Google Apps premier vs Standard storage
Speed
Intel Core 2 Quad vs Core 2 Duo

8. Ways to Create Versions
Functionality
Windows Vista versions
iPod Shuffle vs iPod Nano
Annoyance
Ads vs no ads
Shareware
Support
Self-support vs assistance
Speed and cost of support response

9. Why Version?
Different users have different preferences over various product characteristics.
A seller cannot easily identify an individual buyer’s preferences.
Offering different versions allows buyers to self-select into different groups based on their preferences.
Attempt to extract higher price from those who value certain characteristics more than others.

10. Designing Versions
Need information about consumers’ willingness to pay for different features or characteristics.
Profits depend on both the prices and characteristics of the different versions and consumers’ preferences over the characteristics.
Objective is to get consumers with high willingness to pay to buy the ‘high-end’ version and consumers with low willingness to pay to buy the ‘low-end’ version.

11. Designing Versions
If done correctly, versioning can extract more revenues from consumers compared to offering a single version.
Need to make sure that the low-end version is not so attractive that everyone wants to buy it.
Marketing is important.
Don’t make low-end buyers feel like they’re buying a crippled product.
Creative Labs disabled soundcard features in software.
Don’t make high-end buyers feel like they’re getting ripped off.
Sony charged extra for laptops without unnecessary software installed.

12. Versioning Model
Suppose there are two consumers, consumer 1 and consumer 2.
Consumers differ according to their willingness to pay for ‘quality’.
A monopoly sells two different versions of a product to the two consumers, version A (‘high-end’) and version B (‘low-end’).
The firm does not know the identity of each consumer.

13. Versioning Model
Each consumer has a different marginal willingness to pay for quality curve.
Marginal
WTP
Shows the extra amount a consumer is willing to pay as the quality level increases.
It is like a “demand curve” for quality.
Quality level

14. Versioning Model
At a given quality level, the area under the curve shows a consumer’s total willingness to pay for a good of that quality level.
Marginal
WTP
K: Total amount the consumer is willing to pay for a good of quality q0.
K+L: Total amount the consumer is willing to pay for a good of quality q1. K
Not willing to pay extra for quality increases beyond this level. L q0 q1
Quality level

15. Versioning Model
Assume consumer 2 has relatively low willingness to pay for quality compared to consumer 1.
Marginal
WTP
The firm knows what the curves U1 and U2 look like, but does not know which consumer is 1 and which is 2. U1 U2
Quality level

16. Versioning Model
Sell high-quality version A at price pA and low-quality version B at price pB.
Note the prices must be set so that consumer 1 prefers version A over version B.
Marginal
WTP Y X Z qB qA
Quality level

17. Versioning Model
Suppose quality is costless, so the firm sets qA and qB at the highest level where consumers are not willing to pay any extra for higher quality.
Charge a price of pB = X for the low quality version.
Maximum price that consumer 2 is willing to pay.
Consumer 1 gets X + Y + Z – pA from the high-quality version.
Consumer 1 gets X + Y – X = Y from the low-quality version.
Price of the low-quality version

18. Versioning Model
So to induce consumer 1 to buy the high-quality version, we must have: X + Y + Z – pA ≥ Y Or pA ≤ X + Z, so the highest price we can charge for the high-quality version is pA = X + Z.
Total profit given these quality levels is p = pA + pB = X + Z + X = 2X + Z.

19. Example 1
Consumer 1’s marginal willingness to pay for quality is U1 = 20 – q and consumer 2’s is U2 = 10 – q.
Suppose quality is costless and qA = 20 and qB = 10 are chosen.
Questions:
What is the maximum price that can be charged for version B so that consumer 2 buys it?
What is the maximum price that can be charged for version A so that consumer 1 buys version A and not version B?
What is the profit at these prices?

20. Designing the Versions
We’ve found the maximum profit given the quality levels qA and qB.
But are these the profit-maximising quality levels?
We can’t make the consumers pay any more by increasing the quality levels.
Marginal willingness to pay for extra quality is already zero.
But what if we reduce the low quality level?

21. Designing the Versions
Suppose we reduce qB a little:
We have to cut pB by this much:
Marginal
WTP
But we can increase pA by this much:
=> Profits increase
qB’ qB qA
Quality level

22. Designing the Versions
Why does this work?
Note X1 + X2 = X and Y1 + Y2 = Y
Consumer 2’s willingness to pay for version B reduces to X1, so set pB = X1
Consumer 1 gets X1 + X2 + Y1 + Y2 + Z – pA from version A.
Consumer 1 gets Y1 + X1 – X1 = Y1 from version B
=> Max price for version A is pA = X1 + X2 + Y2 + Z = X + Y2 + Z
This is greater than the previous maximum price of X + Z
Marginal
WTP Y1
Profit increases because Y2 > X2 Y2 X1 Z
qB’ qB qA
Quality level X2

23. Example 2 As in the previous example, U1 = 20 – q and U2 = 10 – q.
Question:
Starting from qA = 20 and qB = 10, show that profit can be increased by reducing qB to 5 while keeping qA constant.

24. Designing the Versions
The profit-maximising quality level of the low-end version is where the marginal changes in willingness to pay exactly offset.
Marginal
WTP
At qB*, the gain in willingness to pay of consumer 1 for the high-end version from a reduction in qB exactly equals the loss in willingness to pay of consumer 2 for the low-end version.
Gain
Loss
qB* qA
Quality level