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Publikationer (7 of 7) Visa alla publikationer
Granlund, D. & Sundström, D. (2018). Physicians prescribing originals causes welfare losses. Economics Letters, 170, 143-146
Öppna denna publikation i ny flik eller fönster >>Physicians prescribing originals causes welfare losses
2018 (Engelska)Ingår i: Economics Letters, ISSN 0165-1765, E-ISSN 1873-7374, Vol. 170, s. 143-146Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We analyze 319,000 choices of medically equivalent drugs at Swedish pharmacies. The results show that patients dislike substitutions for the prescribed product and that this effect is larger when the prescribed product is an original. At the same time, patients have strong preferences to buy the cheapest generic product. This implies that patients in most cases buy the cheapest generic product and experience welfare losses when the physician has prescribed another product.

Ort, förlag, år, upplaga, sidor
Elsevier, 2018
Nyckelord
Doctors, Pharmaceuticals, Prescription drugs, Generic drugs, Welfare
Nationell ämneskategori
Nationalekonomi
Forskningsämne
nationalekonomi
Identifikatorer
urn:nbn:se:umu:diva-150411 (URN)10.1016/j.econlet.2018.06.017 (DOI)000442065400035 ()2-s2.0-85048892762 (Scopus ID)
Forskningsfinansiär
Jan Wallanders och Tom Hedelius stiftelse, P2016-0113:1
Tillgänglig från: 2018-08-07 Skapad: 2018-08-07 Senast uppdaterad: 2023-03-23Bibliografiskt granskad
Sundström, D. (2017). Hur avgör vi om teorierna stämmer?. In: Andreas Bergh, Helena Holmlund, Johanna Möllerström, Maria Persson, Robert Östling (Ed.), Nationalekonomins frågor: (pp. 45-70). Lund
Öppna denna publikation i ny flik eller fönster >>Hur avgör vi om teorierna stämmer?
2017 (Svenska)Ingår i: Nationalekonomins frågor / [ed] Andreas Bergh, Helena Holmlund, Johanna Möllerström, Maria Persson, Robert Östling, Lund, 2017, s. 45-70Kapitel i bok, del av antologi (Övrigt vetenskapligt)
Ort, förlag, år, upplaga, sidor
Lund: , 2017
Nationell ämneskategori
Nationalekonomi
Identifikatorer
urn:nbn:se:umu:diva-137581 (URN)9789144114934 (ISBN)
Tillgänglig från: 2017-07-05 Skapad: 2017-07-05 Senast uppdaterad: 2018-06-09Bibliografiskt granskad
Sundström, D. (2016). A comparison of techniques to evaluate policies in public procurement. Umeå: Umeåa universitet
Öppna denna publikation i ny flik eller fönster >>A comparison of techniques to evaluate policies in public procurement
2016 (Engelska)Rapport (Övrigt vetenskapligt)
Abstract [en]

Empirical evaluations of policies implemented through public procurements are commonly carried out using linear regressions or by more involved non-linear structural models. The aspiration is typically to determine a marginal effect. Here, I compare marginal effects generated under both types of specifications. I study how a political initiative to make firms less environmentally damaging implemented through public procurements influences Swedish firms’ behavior. The collected evidence brings about statistically as well as economically significant effects on firms’ bids and costs.

Ort, förlag, år, upplaga, sidor
Umeå: Umeåa universitet, 2016. s. 25
Serie
Umeå economic studies, ISSN 0348-1018 ; 928
Nyckelord
binding function, green public procurement, indirect inference, orthogonal polynomial regression, simulation estimation, structural estimation
Nationell ämneskategori
Nationalekonomi
Identifikatorer
urn:nbn:se:umu:diva-121688 (URN)
Tillgänglig från: 2016-06-07 Skapad: 2016-06-07 Senast uppdaterad: 2018-06-07Bibliografiskt granskad
Sundström, D. (2016). On specification and inference in the econometrics of public procurement. (Doctoral dissertation). Umeå: Umeå universitet
Öppna denna publikation i ny flik eller fönster >>On specification and inference in the econometrics of public procurement
2016 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Abstract [en]

In Paper [I] we use data on Swedish public procurement auctions for internal regularcleaning service contracts to provide novel empirical evidence regarding green publicprocurement (GPP) and its effect on the potential suppliers’ decision to submit a bid andtheir probability of being qualified for supplier selection. We find only a weak effect onsupplier behavior which suggests that GPP does not live up to its political expectations.However, several environmental criteria appear to be associated with increased complexity,as indicated by the reduced probability of a bid being qualified in the postqualificationprocess. As such, GPP appears to have limited or no potential to function as an environmentalpolicy instrument. In Paper [II] the observation is made that empirical evaluations of the effect of policiestransmitted through public procurements on bid sizes are made using linear regressionsor by more involved non-linear structural models. The aspiration is typically to determinea marginal effect. Here, I compare marginal effects generated under both types ofspecifications. I study how a political initiative to make firms less environmentally damagingimplemented through public procurement influences Swedish firms’ behavior. Thecollected evidence brings about a statistically as well as economically significant effect onfirms’ bids and costs. Paper [III] embarks by noting that auction theory suggests that as the number of bidders(competition) increases, the sizes of the participants’ bids decrease. An issue in theempirical literature on auctions is which measurement(s) of competition to use. Utilizinga dataset on public procurements containing measurements on both the actual and potentialnumber of bidders I find that a workhorse model of public procurements is bestfitted to data using only actual bidders as measurement for competition. Acknowledgingthat all measurements of competition may be erroneous, I propose an instrumental variableestimator that (given my data) brings about a competition effect bounded by thosegenerated by specifications using the actual and potential number of bidders, respectively.Also, some asymptotic results are provided for non-linear least squares estimatorsobtained from a dependent variable transformation model. Paper [VI] introduces a novel method to measure bidders’ costs (valuations) in descending(ascending) auctions. Based on two bounded rationality constraints bidders’costs (valuations) are given an imperfect measurements interpretation robust to behavioraldeviations from traditional rationality assumptions. Theory provides no guidanceas to the shape of the cost (valuation) distributions while empirical evidence suggeststhem to be positively skew. Consequently, a flexible distribution is employed in an imperfectmeasurements framework. An illustration of the proposed method on Swedishpublic procurement data is provided along with a comparison to a traditional BayesianNash Equilibrium approach.

Ort, förlag, år, upplaga, sidor
Umeå: Umeå universitet, 2016. s. 15
Serie
Umeå economic studies, ISSN 0348-1018 ; 931
Nyckelord
auctions, dependent variable transformation model, green public procurement, indirect inference, instrumental variable, latent variable, log-generalized gamma distribution, maximum likelihood, measurement error, non-linear least squares, objective effectiveness, orthogonal polynomial regression, prediction, simulation estimation, structural estimation
Nationell ämneskategori
Nationalekonomi
Forskningsämne
nationalekonomi; ekonometri
Identifikatorer
urn:nbn:se:umu:diva-121681 (URN)978-91-7601-507-0 (ISBN)
Disputation
2016-09-02, Hörsal D, Samhällsvetarhuset, Biblioteksgränd 6, Umeå, 13:15 (Engelska)
Opponent
Handledare
Tillgänglig från: 2016-06-08 Skapad: 2016-06-07 Senast uppdaterad: 2024-01-17Bibliografiskt granskad
Sundström, D. (2016). The Competition Effect in a Public Procurement Model: An error-in-variables approach. Umeå University
Öppna denna publikation i ny flik eller fönster >>The Competition Effect in a Public Procurement Model: An error-in-variables approach
2016 (Engelska)Rapport (Övrigt vetenskapligt)
Abstract [en]

Auction theory suggests that as the number of bidders (competition) increases, the sizes of the participants’ bids decrease. An issue in the empirical literature on auctions is which measurement(s) of competition to use. Utilizing a dataset on public procurements containing measurements on both the actual and potential number of bidders I find that a workhorse model of public procurements is best fitted to data using only actual bidders as measurement for competition. Acknowledging that all measurements of competition may be erroneous, I propose an instrumental variable estimator that (given my data) brings about a competition effect bounded by those generated from models using the actual and potential number of bidders, respectively. Also, some asymptotic results are provided for non-linear least squares estimators obtained from a dependent variable transformation model.

Ort, förlag, år, upplaga, sidor
Umeå University, 2016. s. 33
Serie
Umeå economic studies, ISSN 0348-1018 ; 920
Nyckelord
dependent variable transformation model, instrumental variable, measurement error, non-linear least squares
Nationell ämneskategori
Nationalekonomi
Forskningsämne
ekonometri; nationalekonomi
Identifikatorer
urn:nbn:se:umu:diva-114556 (URN)
Tillgänglig från: 2016-01-25 Skapad: 2016-01-25 Senast uppdaterad: 2020-07-09Bibliografiskt granskad
Lundberg, S., Marklund, P.-O., Strömbäck, E. & Sundström, D. (2015). Using public procurement to implement environmental policy: an empirical analysis. Environmental Economics and Policy Studies, 17(4), 487-520
Öppna denna publikation i ny flik eller fönster >>Using public procurement to implement environmental policy: an empirical analysis
2015 (Engelska)Ingår i: Environmental Economics and Policy Studies, ISSN 1432-847X, E-ISSN 1867-383X, Vol. 17, nr 4, s. 487-520Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Politicians expect Green public procurement (GPP) to serve as an environmental policy instrument. However, in order for GPP to work as an effective policy instrument it is important to take into consideration potential suppliers’ decisions to participate in the procurement process, the total number of bidders, and the screening of bidders with respect to mandatory green criteria. The aim of this paper is to empirically study GPP in this respect. The analysis presented here is based on data from Swedish cleaning services procurements that are unique in that they contain very detailed information on various environmental standards set by the contracting authorities. We find at best only a weak effect on supplier behavior, and this suggests that the use of GPP in this situation does not live up to its political expectations. 

Nyckelord
public procurement, auctions, environmental policy, Green Public Procurement, sustainability, purchasing
Nationell ämneskategori
Ekonomi och näringsliv Nationalekonomi
Forskningsämne
biologi, miljövetenskap
Identifikatorer
urn:nbn:se:umu:diva-98079 (URN)10.1007/s10018-015-0102-9 (DOI)000211999000002 ()2-s2.0-84942817185 (Scopus ID)
Projekt
Green Public Procurement
Forskningsfinansiär
Vetenskapsrådet
Tillgänglig från: 2015-01-15 Skapad: 2015-01-15 Senast uppdaterad: 2024-01-17Bibliografiskt granskad
Sundström, D. (2014). It’s all in the interval: an imperfect measurements approach to estimate bidders’ primitives in auctions. Umeå: Umeå universitet
Öppna denna publikation i ny flik eller fönster >>It’s all in the interval: an imperfect measurements approach to estimate bidders’ primitives in auctions
2014 (Engelska)Rapport (Övrigt vetenskapligt)
Abstract [en]

A novel methodology to measure bidders’ costs (valuations) in descending (ascending) auctions is introduced. Based on two bounded rationality constraints bidders’ costs (valuations) are given an imperfect measurements interpretation that is robust to behavioral deviations from the traditional rationality assumptions. Theory provides no guidance as to the shape of the cost (valuation) distributions while empirical evidence suggests them to be positively skew. Consequently, a flexible distribution is employed in an imperfect measurements framework. An illustration of the proposed methodology on Swedish public procurement data is provided along with a comparison to a traditional Bayesian Nash Equilibrium methodology.

Ort, förlag, år, upplaga, sidor
Umeå: Umeå universitet, 2014. s. 21
Serie
Umeå economic studies, ISSN 0348-1018 ; 899
Nyckelord
log-generalized gamma distribution, latent variable, maximum likelihood, prediction, public procurement
Nationell ämneskategori
Nationalekonomi
Forskningsämne
nationalekonomi; ekonometri
Identifikatorer
urn:nbn:se:umu:diva-95896 (URN)
Tillgänglig från: 2014-11-06 Skapad: 2014-11-06 Senast uppdaterad: 2018-06-07Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0003-1312-8073

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