| fish {wooldridge} | R Documentation |
fish
Description
Wooldridge Source: K Graddy (1995), “Testing for Imperfect Competition at the Fulton Fish Market,” RAND Journal of Economics 26, 75-92. Professor Graddy's collaborator on a later paper, Professor Joshua Angrist at MIT, kindly provided me with these data. Data loads lazily.
Usage
data('fish')
Format
A data.frame with 97 observations on 20 variables:
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prca: price for Asian buyers
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prcw: price for white buyers
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qtya: quantity sold to Asians
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qtyw: quantity sold to whites
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mon: =1 if Monday
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tues: =1 if Tuesday
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wed: =1 if Wednesday
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thurs: =1 if Thursday
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speed2: min past 2 days wind speeds
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wave2: avg max last 2 days wave height
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speed3: 3 day lagged max windspeed
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wave3: avg max wave hghts of 3 & 4 day lagged hghts
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avgprc: ((prca*qtya) + (prcw*qtyw))/(qtya + qtyw)
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totqty: qtya + qtyw
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lavgprc: log(avgprc)
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ltotqty: log(totqty)
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t: time trend
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lavgp_1: lavgprc[_n-1]
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gavgprc: lavgprc - lavgp_1
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gavgp_1: gavgprc[_n-1]
Notes
This is a nice example of how to go about finding exogenous variables to use as instrumental variables. Often, weather conditions can be assumed to affect supply while having a negligible effect on demand. If so, the weather variables are valid instrumental variables for price in the demand equation. It is a simple matter to test whether prices vary with weather conditions by estimating the reduced form for price.
Used in Text: pages 443, 580
Source
https://www.cengage.com/cgi-wadsworth/course_products_wp.pl?fid=M20b&product_isbn_issn=9781111531041
Examples
str(fish)