Panos Ipeirotis

Stern School of BusinessNew York University

Opinion Mining Using Econometrics

Comparative Shopping

Comparative Shopping

Are Customers Irrational?

$11.04 (+1.5%)

BuyDig.com getsPrice Premium

(customers pay more thanthe minimum price)

Price Premiums / Discounts @ Amazon

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Are Buyers

Irrational (?)

(paying more)

Are Sellers Irrational (?)(charging less)

Why not Buying the Cheapest?

You buy more than a product

Customers do not pay only for the product Customers also pay for a set of fulfillment characteristics

Delivery Packaging Responsiveness …

Customers care about reputation of sellers!

Example of a reputation profile

The Idea in a Single Slide

Conjecture: Price premiums measure reputation

Reputation is captured in text feedback

Our contribution: Examine how text affects price premiums

(and learn to rank opinion phrases as a side effect)

ACL 2007

Decomposing Reputation

Is reputation just a scalar metric?

Previous studies assumed a “monolithic” reputation Decompose reputation in individual components Sellers characterized by a set of fulfillment characteristics

(packaging, delivery, and so on)

What are these characteristics (valued by consumers?)

We think of each characteristic as a dimension, represented by a noun, noun phrase, verb or verbal phrase (“shipping”, “packaging”, “delivery”, “arrived”)

We scan the textual feedback to discover these dimensions

Decomposing and Scoring ReputationDecomposing and scoring reputation

We think of each characteristic as a dimension, represented by a noun or verb phrase (“shipping”, “packaging”, “delivery”, “arrived”)

The sellers are rated on these dimensions by buyers using modifiers (adjectives or adverbs), not numerical scores “Fast shipping!” “Great packaging” “Awesome unresponsiveness” “Unbelievable delays” “Unbelievable price”

How can we find out the meaning of these adjectives?

Measuring Reputation

• Regress textual reputation against price premiums

• Example for “delivery”:– Fast delivery vs. Slow delivery: +$7.95– So “fast” is better than “slow” by a $7.95 margin

Some Indicative Dollar ValuesPositive Negative

Natural method for extracting sentiment strength and polarity

good packaging -$0.56

Naturally captures the pragmatic meaning within the given context

captures misspellings as well

Positive? Negative?

Feature Weights for Digital Cameras

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SLRPoint & Shoot

Other Applications

• Financial news and price/variance prediction

• Hotel search and personalization

• Measuring (and predicting) importance of political events

• Deriving better keyword bidding, pricing, and ad generation strategies

Thank you!

Questions?

panos@nyu.edu

http://economining.stern.nyu.edu

Overflow

Charts

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DataOverview Panel of 280 software products sold by Amazon.com X 180 days Data from “used goods” market

Amazon Web services facilitate capturing transactions We do not use any proprietary Amazon data (Details in the paper)

Data: Secondary Marketplace

Data: Capturing Transactions

time

Jan 1 Jan 2 Jan 3 Jan 4 Jan 5 Jan 6 Jan 7 Jan 8

We repeatedly “crawl” the marketplace using Amazon Web ServicesWhile listing appears item is still available no sale

Data: Capturing Transactions

time

Jan 1 Jan 2 Jan 3 Jan 4 Jan 5 Jan 6 Jan 7 Jan 8 Jan 9 Jan 10

We repeatedly “crawl” the marketplace using Amazon Web ServicesWhen listing disappears item sold

Capturing Transactions

Capturing transactions and “price premiums”

Data: Transactions

Seller ListingItem Price

When item is sold, listing disappears

Capturing transactions and “price premiums”

Data: Transactions

While listing appears, item is still available

time

Jan 1 Jan 2 Jan 3 Jan 4 Jan 5 Jan 6 Jan 7 Jan 8 Jan 9 Jan 10

Capturing transactions and “price premiums”

Data: Transactions

While listing appears, item is still available

time

Jan 1 Jan 2 Jan 3 Jan 4 Jan 5 Jan 6 Jan 7 Jan 8 Jan 9 Jan 10

Item still not sold on 1/7

Capturing transactions and “price premiums”

Data: Transactions

When item is sold, listing disappears

time

Item sold on 1/9

Jan 1 Jan 2 Jan 3 Jan 4 Jan 5 Jan 6 Jan 7 Jan 8 Jan 9 Jan 10

Reputation Tools

Seller: uCameraSite.com

1. Canon Powershot x3002. Kodak - EasyShare 5.0MP 3. Nikon - Coolpix 5.1MP 4. Fuji FinePix 5.15. Canon PowerShot x900

Reputation Pricing Tool for Sellers

Your last 5 transactions in CamerasName of product Price

Seller 1 - $431

Seller 2 - $409

You - $399

Seller 3 - $382

Seller 4-$379

Seller 5-$376

Canon Powershot x300Your competitive landscapeProduct Price (reputation)

(4.8)

(4.65)

(4.7)

(3.9)

(3.6)

(3.4)

Your Price: $399Your Reputation Price: $419Your Reputation Premium: $20 (5%)

$20

Left on the table

25%

14%

7%

45%

9%

Quantitatively Understand & Manage Seller Reputation

RSI Tool for Seller Reputation Management

How your customers see you relative to other sellers:

35%*69%89%

82%95%

ServicePackagingDelivery

OverallQuality

Dimensions of your reputation and the relative importance to your customers:

Service

Packaging

Delivery

Quality

Other* Percentile of all merchants

• RSI Products Automatically Identify the Dimensions of Reputation from Textual Feedback• Dimensions are Quantified Relative to Other Sellers and Relative to Buyer Importance• Sellers can Understand their Key Dimensions of Reputation and Manage them over Time• Arms Sellers with Vital Info to Compete on Reputation Dimensions other than Low Price.

Marketplace Search

Buyer’s Tool

Used Market (ex: Amazon)

Price Range $250-$300

Seller 1 Seller 2

Seller 4 Seller 3

Sort by Price/Service/Delivery/other dimensions

Canon PS SD700

ServicePackaging

Delivery

Price

Dimension Comparison

Seller 1

Price Service Package Delivery

Seller 2

Seller 3

Seller 4

Seller 5

Seller 6

Seller 7