Title: The productivity impact of ecommerce in
1 The productivity impact of e-commerce in the UK,
2001 and 2002 Evidence from Microdata
Ana Rincon, Catherine Robinson and Michela
Vecchi.
2Introduction
ICT capital
Network
Productivity
3Aims of the paper
- How does the Internet E-commerce affect company
performance? - Are the production and service sectors using
e-commerce in the same way? - Does the impact of e-commerce on productivity
differ from 2001 to 2002? - EDI versus Internet. Do we obtain consistent
results?
4Electronic networks listed in the E-commerce
survey
- External email
- Intranet
- Extranet
- EDI
- Interactive telephony
- Mobile technology
- Digital TV
- Internet
Other electronic networks
5Computer networks and enterprise performance
- Existing evidence
- Rowlatt (2001)
- The Economist survey
- Clayton Criscuolo (2002)
- Improve the effectiveness of RD
- Facilitates access to wider markets
- Improves business processes
- Atrostic and Nguyen (2004)
- Criscuolo Waldron (2003)
6E-commerce survey 2001 and 2002
- E-commerce 2001 and 2002 are very comparable. The
only differences are in the order of the
questions and survey design. - Sample size increased from 9,000 businesses in
2000 to 12,000 in 2001 and 2002. - In 2000 business of lt10 employees were excluded,
In 2001/2002 all businesses included. - E-commerce 2001 and 2002 main questions
7Connectivity measures
8Use of Internet for placing/receiving orders
2001 and 2002
9Network of systems 2001 and 2002
Integration indicator
10ABI and E-Commerce
- The data used here
- The Ecommerce survey is a relatively small sample
(only 12,000 enterprises included). - Williams (2001) Clayton and Criscuolo (2002)
description of the data . - Number of enterprises
11Modelling productivity - 1
- Gross output specification including intermediate
materials (Baily 86, Basu and Fernald 97,
Atrostic and Nguyen 04) - We focus on e-buy and e-sell plus a combined
variable, e-trade. - We include a set of control variables
Multiplant, Foreign ownership, Age of the
reporting unit, Industry and Region.
12Modelling productivity - 2
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13Table 4 cross section results 2001, OLS
14Table 4 cross section results 2002 , OLS
15Table 4 cont. Impact of trading on the
Internet 2001 and 2002 - OLS
16Selection bias and treatment
- OLS results are likely to be inconsistent because
of the correlation between explanatory variables
and residuals, which capture effects of all
omitted and imperfectly measured variables. - e.g. Correlation between the decision of trading
on the web and able management, IT skills etc. - Selectivity bias
We instrument the endogenous binary
variable (treatment effect estimator)
17Treatment effect estimator - 1
- Considers effect of endogenously chosen binary
variable on another endogenous continuous
variable, conditional on two sets of independent
variables. - Two alternative estimation techniques
- 2sls (probit in the first stage, OLS in the
second). - Maximum likelihood estimator - just one step
therefore more efficient. - We estimate two regressions simultaneously
18Treatment effect estimator - 2
1)
2)
19Treatment effect estimator - 3The instrument set
(Z)
- Instrument relevance Need that endogenous
variable X and instruments Z are correlated - - Stock and Yogo (2004) test for weak
instruments, based on the regression of
endogenous X on all Z. It is based on comparing
the F statistics with the critical values
supplied in their paper.
- Instrument exogeneity Need Z to be uncorrelated
- with ei, , the error term in the equation of
interest - - To test this
- Calculate residual from each OLS regression
- Regress residual on all instruments controls
and discard if coefficients are significantly
different from zero. -
20Instruments for 2001 correlation with the
residuals
- Results of regressing the residual on the
instruments - e-buy
- Results of regressing the residual on the
instruments - e-sell
21Instruments for 2002 correlation with the
residuals
- Results of regressing the residual on the
instruments - e-buy
- Results of the residual on the instruments -
e-sell
22 Table 5 The impact of buying on the Internet
on productivity 2001
All Sectors
Production
Services
Constant
1.596
1.497
1.783
(0.085)
(.121)
(.192)
Emp
0.271
0.225
0.286
(.015)
(.024)
(.018)
K (2001)
0.108
0.090
0.125
(.020)
(.029)
(.027)
Inter
0.623
0.675
0.594
(.021)
(.036)
(.027)
e-buy
0.084
0.125
0.074
(.044)
(.164)
(.064)
L. ratio test
2.96
0.44
1.09
(.085)
(.508)
(.029)
23 Table 5 The impact of buying on the Internet
on productivity 2002
All Sectors
Production
Services
Constant
1.753
1.265
2.133
(.094)
(.091)
(.182)
Emp
0.247
0.232
0.250
(.015)
(.020)
(.016)
K (2001)
0.100
0.073
0.104
(.0178)
(.021)
(.022)
Inter
0.644
0.703
0.630
(.018)
(.032)
(.021)
e-buy
0.090
0.406
0.122
(.046)
(.087)
(.054)
L. ratio test
2.40
13.63
4.04
(.121)
(.000)
(.044)
24Table 5 cont The impact of trading on the
Internet on productivity 2001 and 2002-Treatment
25Conclusions
- OLS
- In 2001 We do not find any significant impact of
E-commerce on productivity. - In 2002 We only find a positive impact of buying
in the production sector (Criscuolo and Waldron,
2003) and selling in the service sector. -
- Correcting for selectivity bias
- In 2001 The effect of buying is positive and
significant for the total sample, while e-sell is
significant in production. - In 2002 The coefficient for both buying and
selling on the Internet are significantly
positive in both production and services, with
always a higher impact in the production sector.
26Further work
- Look at the relationship between EDI and
Internet. - Extend the analysis using E-commerce for 2003, to
provide better evidence of how the impact of
e-commerce on productivity has changed over time.
- Look at the panel dimension, even though only
large firms are represented - Compare the UK experience with other countries
(e.g. Germany)