International Journal of Industrial Organization
2007, Volume 25, Issue 1
- 173-185 Welfare reductions from small cost reductions in differentiated oligopoly
by Wang, X. Henry & Zhao, Jingang
- 187-199 OPEC and the international oil market: Can a cartel fuel the engine of economic development?
by Noguera, Jose & Pecchecnino, Rowena A.
- 201-217 Reexamining the effect of the most-favored-nation provision in input prices on R and D incentives
by Kim, Jeong-Yoo & Nahm, Jae
2006, Volume 24, Issue 6
- 1079-1082 The economics of cartels, cartel policy, and collusion: Introduction to the special issue
by Hinloopen, Jeroen & Martin, Stephen
- 1083-1107 Examining models of collusion: The market for lysine
by de Roos, Nicolas
- 1109-1137 Cartel overcharges: Survey and meta-analysis
by Connor, John M. & Bolotova, Yuliya
- 1139-1156 On the use of low-price guarantees to discourage price cutting
by Arbatskaya, Maria & Hviid, Morten & Shaffer, Greg
- 1157-1184 The risk of contagion from multimarket contact
by Thomas, Charles J. & Willig, Robert D.
- 1185-1212 Cartel pricing dynamics with cost variability and endogenous buyer detection
by Harrington, Joseph Jr. & Chen, Joe
- 1213-1229 Internal cartel stability with time-dependent detection probabilities
by Hinloopen, Jeroen
- 1231-1240 On optimal cartel deterrence policies
by Frezal, Sylvestre
- 1241-1266 The impact of leniency and whistle-blowing programs on cartels
by Aubert, Cecile & Rey, Patrick & Kovacic, William E.
- 1267-1297 Imperfect competition law enforcement
by Schinkel, Maarten Pieter & Tuinstra, Jan
- 1299-1332 Competition policy, collusion, and tacit collusion
by Martin, Stephen
2006, Volume 24, Issue 5
- 867-885 Corruption in procurement and public purchase
by Auriol, Emmanuelle
- 887-906 The interaction of task and asset allocation
by Corts, Kenneth S.
- 907-913 Why the music industry may gain from free downloading -- The role of sampling
by Peitz, Martin & Waelbroeck, Patrick
- 915-929 Relationship lending under asymmetric information: A case of blocked entry
by Tassel, Eric Van
- 931-952 Should good patents come in small packages? A welfare analysis of intellectual property bundling
by Gilbert, Richard J. & Katz, Michael L.
- 953-970 The hold-up problem in a repeated relationship
by Castaneda, Marco A.
- 971-993 Does the market value R&D investment by European firms? Evidence from a panel of manufacturing firms in France, Germany, and Italy
by Hall, Bronwyn H. & Oriani, Raffaele
- 995-1011 Bounding the relative profitability of price discrimination
by Malueg, David A. & Snyder, Christopher M.
- 1013-1020 Access price regulation, investment and entry in telecommunications
by Kotakorpi, Kaisa
- 1021-1040 Firm spin-offs in Denmark 1981-2000 -- patterns of entry and exit
by Eriksson, Tor & Moritz Kuhn, Johan
- 1041-1069 Entry order and pricing over the product cycle: The transition from the 486 to the Pentium processor
by Deltas, George & Zacharias, Eleftherios
- 1071-1076 A note on the excess entry theorem in spatial markets
by Matsumura, Toshihiro & Okamura, Makoto
- 1077-1077 Addendum to "Theory and evidence on pricing by asymmetric oligopolies" [Int. J. Ind. Organ. 24 (2006) 83-105]
by Kocas, Cenk & Kiyak, Tunga
2006, Volume 24, Issue 4
- 667-682 Evidence on preferences and subjective beliefs of risk takers: The case of smokers
by Khwaja, Ahmed & Sloan, Frank & Salm, Martin
- 683-699 Learning about individual risk and the decision to smoke
by Khwaja, Ahmed & Sloan, Frank & Chung, Sukyung
- 701-713 Silent interests and all-pay auctions
by Konrad, Kai A.
- 715-731 On the competitive effects of vertical integration by a research laboratory
by Sandonis, Joel & Fauli-Oller, Ramon
- 733-751 Foreign ownership and productivity: Is the direction of causality so obvious?
by Benfratello, Luigi & Sembenelli, Alessandro
- 753-762 Differentiation and discrimination in a duopoly with two bundles
by Vaubourg, Anne-Gael
- 763-771 Service hours with asymmetric distributions of ideal service time
by Shy, Oz & Stenbacka, Rune
- 773-783 Supply function vs. quantity competition in supergames
by Ciarreta, Aitor & Gutierrez-Hita, Carlos
- 785-793 Information disadvantage in linear Cournot duopolies with differentiated products
by Chokler, Adi & Hon-Snir, Shlomit & Kim, Moshe & Shitovitz, Benyamin
- 795-808 Access pricing and investment with stochastically growing demand
by Hori, Keiichi & Mizuno, Keizo
- 809-834 Firm size distribution: Testing the "independent submarkets model" in the Italian motor insurance industry
by Buzzacchi, Luigi & Valletti, Tommaso M.
- 835-866 Impacts of code-share alliances on airline cost structure: A truncated third-order translog estimation
by Goh, Mark & Yong, Jongsay
2006, Volume 24, Issue 3
- 467-486 A variance screen for collusion
by Abrantes-Metz, Rosa M. & Froeb, Luke M. & Geweke, John & Taylor, Christopher T.
- 487-503 Delegation versus an approval process and the demand for talent
by Marino, Anthony M.
- 505-520 A laboratory study of haggling with deadlines
by Milam, Garrett
- 521-540 Quality competition in retailing: A structural analysis
by Ellickson, Paul B.
- 541-554 Price vs. quantity in oligopoly games
by Tasnadi, Attila
- 555-581 Using first-price auctions to sell heterogeneous licenses
by Goeree, Jacob K. & Offerman, Theo & Schram, Arthur
- 583-591 A note on cost arrangement and market performance in a multi-product Cournot oligopoly
by Lapan, Harvey E. & Hennessy, David A.
- 593-604 Bid preference in license auctions: Affirmative action can achieve economic efficiency
by Yoon, Kiho
- 605-611 Welfare and output in third-degree price discrimination: A note
by Galera, Francisco & Zaratiegui, Jesus M.
- 613-628 The loss leader is a turkey: Targeted discounts from multi-product competitors
by DeGraba, Patrick
- 629-637 Quality-improving alliances in differentiated oligopoly
by Deroian, Frederic & Gannon, Frederic
- 639-665 An experimental study of price dispersion in an optimal search model with advertising
by Cason, Timothy N. & Datta, Shakun
2006, Volume 24, Issue 2
- 203-225 The (teaching) role of universities in the diffusion of the Internet
by Goldfarb, Avi
- 227-250 Endogenous mergers in endogenous sunk cost industries
by Vasconcelos, Helder
- 251-267 Estimating market power in the presence of capacity constraints: An application to high-fructose corn sweetener
by Brendstrup, Bjarne & Paarsch, Harry J. & Solow, John L.
- 269-285 Contract renewal and incentives in public procurement
by Dalen, Dag Morten & Moen, Espen R. & Riis, Christian
- 287-301 Rivalry between strategic alliances
by Zhang, Anming & Zhang, Yimin
- 303-318 Naked slotting fees for vertical control of multi-product retail markets
by Innes, Robert & Hamilton, Stephen F.
- 319-334 Upstream market power and product line differentiation in retailing
by Avenel, E. & Caprice, S.
- 335-347 Market entry and foreign direct investment
by Stahler, Frank
- 349-380 Spillovers in product and process innovation: Evidence from manufacturing firms
by Ornaghi, Carmine
- 381-400 Science parks in Japan and their value-added contributions to new technology-based firms
by Fukugawa, Nobuya
- 401-423 R&D and M&A: Are cross-border M&A different? An investigation on OECD countries
by Bertrand, Olivier & Zuniga, Pluvia
- 425-448 Value of reputation in the chain-store game with multiple incumbents
by Melkonyan, Tigran A.
- 449-465 Optimal franchise contracts with private cost information
by Hempelmann, Bernd
2006, Volume 24, Issue 1
- 1-28 Price structure in two-sided markets: Evidence from the magazine industry
by Kaiser, Ulrich & Wright, Julian
- 29-43 The role of interchange fees in ATM networks
by Donze, Jocelyn & Dubec, Isabelle
- 45-67 Multihoming and compatibility
by Doganoglu, Toker & Wright, Julian
- 69-81 Collusion with capacity constraints over the business cycle
by Fabra, Natalia
- 83-105 Theory and evidence on pricing by asymmetric oligopolies
by Kocas, Cenk & Kiyak, Tunga
- 107-124 Estimating the extent of potential competition in the Korean mobile telecommunications market: Switching costs and number portability
by Lee, Jongsu & Kim, Yeonbae & Lee, Jeong-Dong & Park, Yuri
- 125-147 Investment and internal finance: Asymmetric information or managerial discretion?
by Degryse, Hans & de Jong, Abe
- 149-175 Patent licensing revisited: Heterogeneous firms and product differentiation
by Hernandez-Murillo, Ruben & Llobet, Gerard
- 177-202 Strategic patent breadth and entry deterrence with drastic product innovations
by Yiannaka, Amalia & Fulton, Murray
2005, Volume 23, Issue 9-10
- 665-668 Editors' introduction
by Neven, Damien J. & Roller, Lars-Hendrik
- 669-691 Quantifying the effects from horizontal mergers in European competition policy
by Ivaldi, Marc & Verboven, Frank
- 693-698 Using merger simulation models: Testing the underlying assumptions
by Hausman, Jerry A. & Leonard, Gregory K.
- 699-702 Quantifying the effects from horizontal mergers: Comments on the underlying assumptions
by Ivaldi, Marc & Verboven, Frank
- 703-715 Pass-through rates and the price effects of mergers
by Froeb, Luke & Tschantz, Steven & Werden, Gregory J.
- 717-737 An econometric analysis of the European Commission's merger decisions
by Bergman, Mats A. & Jakobsson, Maria & Razo, Carlos
- 739-751 An equilibrium approach to international merger policy
by Cabral, Luis M.B.
- 753-775 Hold-up of anti-competitive mergers
by Fridolfsson, Sven-Olof & Stennek, Johan
- 777-801 Efficiency gains and myopic antitrust authority in a dynamic merger game
by Motta, Massimo & Vasconcelos, Helder
- 803-827 On the desirability of an efficiency defense in merger control
by Lagerlof, Johan N.M. & Heidhues, Paul
- 829-848 Consumer surplus vs. welfare standard in a political economy model of merger control
by Neven, Damien J. & Roller, Lars-Hendrik
- iii-iii Paul Geroski
by Martin, Stephen
2005, Volume 23, Issue 7-8
- 505-534 Firm productivity, heterogeneity, sunk costs and market selection
by Fariñas, Jose C. & Ruano, Sonia
- 535-562 The decision to patent, cumulative innovation, and optimal policy
by Erkal, Nisvan
- 563-586 Foreign technology acquisition policy and firm performance in Japan, 1957-1970: Micro-aspects of industrial policy
by Kiyota, Kozo & Okazaki, Tetsuji
- 587-597 Multiproduct firms and market structure: An explorative application to the product life cycle
by Allanson, Paul & Montagna, Catia
- 599-614 Internalization of airport congestion: A network analysis
by Brueckner, Jan K.
- 615-623 Efficient usage and access pricing in telephone networks
by MacDonald, Ian A. & Meriluoto, Laura
- 625-637 Games with strategic complementarities: New applications to industrial organization
by Vives, Xavier
- 639-664 Vertical antitrust policy as a problem of inference
by Cooper, James C. & Froeb, Luke M. & O'Brien, Dan & Vita, Michael G.
2005, Volume 23, Issue 5-6
- 303-323 Skills and innovation
by Leiponen, Aija
- 325-339 Multiplicity of equilibria in search markets with free entry and exit
by Pereira, Pedro
- 341-354 Imperfect price discrimination in a vertical differentiation model
by Liu, Qihong & Serfes, Konstantinos
- 355-379 R&D cooperation between firms and universities. Some empirical evidence from Belgian manufacturing
by Veugelers, Reinhilde & Cassiman, Bruno
- 381-397 Symmetric research joint ventures: Cooperative substitutes and complements
by Leahy, Dermot & Neary, J. Peter
- 399-421 Exit from regional manufacturing markets: The role of entrant experience
by Dunne, Timothy & Klimek, Shawn D. & Roberts, Mark J.
- 423-450 Firm size distributions: An overview of steady-state distributions resulting from firm dynamics models
by de Wit, Gerrit
- 451-466 Truly costly sequential search and oligopolistic pricing
by Janssen, Maarten C.W. & Moraga-Gonzalez, Jose Luis & Wildenbeest, Matthijs R.
- 467-481 Absorptive capacity and connectedness: Why competing firms also adopt identical R&D approaches
by Wiethaus, Lars
2005, Volume 23, Issue 3-4
- 155-181 Price wars and collusion in the Spanish electricity market
by Fabra, Natalia & Toro, Juan
- 183-201 Stochastic synergies in sequential auctions
by De Silva, Dakshina G. & Jeitschko, Thomas D. & Kosmopoulou, Georgia
- 203-225 The competitive effects of exclusive dealing: Evidence from the U.S. beer industry
by Sass, Tim R.
- 227-247 Exit with vertical product differentiation
by Esteve-Perez, Silviano
- 249-261 Endogenous sequential entry in a spatial model revisited
by Gotz, Georg
- 263-278 Relying on information acquired by a principal
by Finkle, Aaron
- 279-302 Concubinage or marriage? Informal and formal cooperations for innovation
by Bonte, Werner & Keilbach, Max
2005, Volume 23, Issue 1-2
- 1-22 The intra-firm diffusion of new process technologies
by Battisti, Giuliana & Stoneman, Paul
- 23-43 Industry shakeouts and technological change
by Klepper, Steven & Simons, Kenneth L.
- 45-62 Honest certification and the threat of capture
by Strausz, Roland
- 63-82 Cooperative and noncooperative R&D in experimental duopoly markets
by Suetens, Sigrid
- 83-108 The effects of learning-by-doing on product innovation by a durable good monopolist
by Kutsoati, Edward & Zabojnik, Jan
- 109-128 Risk, price regulation, and irreversible investment
by Evans, Lewis T. & Guthrie, Graeme A.
- 129-153 Should alternative mergers or acquisitions be considered by antitrust authorities?
by Brito, Duarte
2004, Volume 22, Issue 10
- 1381-1398 Estimation of price-cost margins and union bargaining power for Belgian manufacturing
by Dobbelaere, Sabien
- 1399-1414 Opportunism and menus of two-part tariffs
by Marx, Leslie M. & Shaffer, Greg
- 1415-1441 Promoting competition in the presence of essential facilities
by Grout, Paul A. & Park, In-Uck
- 1443-1462 Are prices 'sticky' online? Market structure effects and asymmetric responses to cost shocks in online mortgage markets
by Arbatskaya, Maria & Baye, Michael R.
- 1463-1484 Economic integration and corruption
by Ganuza, Juan-Jose & Hauk, Esther
2004, Volume 22, Issue 8-9
- 1041-1066 Number of sellers, average prices, and price dispersion
by Barron, John M. & Taylor, Beck A. & Umbeck, John R.
- 1067-1089 The incentives for takeover in oligopoly
by Inderst, Roman & Wey, Christian
- 1091-1114 Technology of upstream firms and equilibrium product differentiation
by Matsushima, Noriaki
- 1115-1135 Spatial proximity and complementarities in the trading of tacit knowledge
by Aydogan, Neslihan & Lyon, Thomas P.
- 1137-1154 Intergenerational effects in the diffusion of new technology: the case of mobile phones
by Liikanen, Jukka & Stoneman, Paul & Toivanen, Otto
- 1155-1182 Upgrading and niche usage of PC operating systems
by Kretschmer, Tobias
- 1183-1211 Entrepreneurs' human capital and the start-up size of new technology-based firms
by Colombo, Massimo G. & Delmastro, Marco & Grilli, Luca
- 1213-1235 Cooperative R&D between vertically related firms with spillovers
by Ishii, Akira
- 1237-1263 Heterogeneity in R&D cooperation strategies
by Belderbos, Rene & Carree, Martin & Diederen, Bert & Lokshin, Boris & Veugelers, Reinhilde
- 1265-1287 Exit option in hierarchical agency
by Kim, Doyoung & Lawarree, Jacques & Shin, Dongsoo
- 1289-1307 Regulation with non-price discrimination
by Sand, Jan Y.
- 1309-1325 A positive theory of give-away privatization
by Debande, Olivier & Friebel, Guido
- 1327-1347 Delegating recruitment under asymmetric information
by Sengupta, Sarbajit
- 1349-1375 Piecewise procurement of a large-scale project
by Yildirim, Huseyin
2004, Volume 22, Issue 7
- 887-915 Strategic debt and patent races
by Jensen, Richard & Showalter, Dean
- 917-949 Financial constraints and product market competition: ex ante vs. ex post incentives
by Povel, Paul & Raith, Michael
- 951-981 Delegated monitoring versus arm's-length contracting
by Dequiedt, Vianney & Martimort, David
- 983-996 Money-back guarantees and market experimentation
by Nizovtsev, Dmitri & Novshek, William
- 997-1015 An alternating-move price-setting duopoly model with stochastic costs
by Eckert, Andrew
- 1017-1038 Collusion under yardstick competition: an experimental study
by Potters, Jan & Rockenbach, Bettina & Sadrieh, Abdolkarim & van Damme, Eric
2004, Volume 22, Issue 6
- 737-757 Nonlinear price discrimination with a finite number of consumers and constrained recontracting
by Hamilton, Jonathan & Slutsky, Steven
- 759-782 Where to locate in a circular city?
by Gupta, Barnali & Lai, Fu-Chuan & Pal, Debashis & Sarkar, Jyotirmoy & Yu, Chia-Ming
- 783-797 Inter-league competition for talent vs. competitive balance
by Palomino, Frederic & Sakovics, Jozsef
- 799-820 Two-part tariff competition in duopoly
by Yin, Xiangkang
- 821-834 Can vertical integration by a monopsonist harm consumer welfare?
by de Fontenay, Catherine C. & Gans, Joshua S.
- 835-848 Idiosyncratic shocks in an asymmetric Cournot oligopoly
by Fevrier, Philippe & Linnemer, Laurent
- 849-861 Private labels: psychological versioning of typical consumer products
by Soberman, David A. & Parker, Philip M.
- 863-884 Shirking and motivations in firms: survey evidence on worker attitudes
by Minkler, Lanse
2004, Volume 22, Issue 5
- 593-609 Non-cooperative networks in oligopolies
by Billand, P. & Bravard, C.
- 611-631 Network competition and interconnection with heterogeneous subscribers
by Hahn, Jong-Hee
- 633-645 Direct and indirect network effects: are they equivalent?
by Clements, Matthew T.
- 647-653 A note on critical masses, network externalities and converters
by Andreozzi, Luciano
- 655-677 Dynamic duopoly with congestion effects
by Laussel, Didier & de Montmarin, Maxime & Van Long, Ngo
- 679-692 The competitive effects of mergers between asymmetric firms
by Thomas, Charles J.
- 693-713 Innovation, market structure and the holdup problem: investment incentives and coordination
by Wickelgren, Abraham L.
- 715-733 Predation due to adverse selection in financial markets
by Fernandez-Ruiz, Jorge
2004, Volume 22, Issue 4
- 443-480 Determinants of opposition against EPO patent grants--the case of biotechnology and pharmaceuticals
by Harhoff, Dietmar & Reitzig, Markus
- 481-502 The effects of mergers on company employment in the USA and Europe
by Gugler, Klaus & Yurtoglu, B. Burcin
- 503-522 Advertising efficiency and the choice of media mix: a case of beer
by Fare, Rolf & Grosskopf, Shawna & Seldon, Barry J. & Tremblay, Victor J.
- 523-540 Persistence in prescriptions of branded drugs
by Richard, Oliver & Van Horn, Larry
- 541-559 Firms' age, process innovation and productivity growth
by Huergo, Elena & Jaumandreu, Jordi
- 561-574 Strategic delegation in experimental markets
by Huck, Steffen & Muller, Wieland & Normann, Hans-Theo
- 575-590 Takeovers and the dynamics of information flows
by Chemla, Gilles
2004, Volume 22, Issue 3
- 289-308 Competing models of firm profitability
by Slade, Margaret E.
- 309-328 Preemption and rent dissipation under price competition
by Boyer, Marcel & Lasserre, Pierre & Mariotti, Thomas & Moreaux, Michel
- 329-350 Barter for price discrimination
by Guriev, Sergei & Kvassov, Dmitri
- 351-387 A model of collusion timing
by de Roos, Nicolas
- 389-411 Resale price maintenance in an oligopoly with uncertain demand
by Wang, Hao
- 413-425 Timing of investments, holdup and total welfare
by Smirnov, Vladimir & Wait, Andrew
- 427-440 Motivating devoted workers
by Glazer, Amihai
2004, Volume 22, Issue 2
- 147-162 Oligopoly competition in fixed cost environments
by Durham, Yvonne & McCabe, Kevin & Olson, Mark A. & Rassenti, Stephen & Smith, Vernon
- 163-184 The limited liability effect in experimental duopoly markets
by Oechssler, Jorg & Schuhmacher, Frank
- 185-192 Vertical foreclosure versus downstream competition with capital precommitment
by Baake, Pio & Kamecke, Ulrich & Normann, Hans-Theo
- 193-217 Cournot versus Walras in dynamic oligopolies with memory
by Alos-Ferrer, Carlos
- 219-239 Product differentiation with consumer arbitrage
by Aguirre, Inaki & Paz Espinosa, Maria
- 241-251 Strategic alliances, joint investments, and market structure
by Eerola, Essi & Maattanen, Niku
- 253-267 Infrastructure quality in deregulated industries: is there an underinvestment problem?
by Buehler, Stefan & Schmutzler, Armin & Benz, Men-Andri
- 269-288 Monitoring and market power in credit markets
by Hyytinen, Ari & Toivanen, Otto
2004, Volume 22, Issue 1
- 1-24 Strategic investments with spillovers, vertical integration and foreclosure in the broadband access market
by Foros, Oystein
- 25-43 Vertical integration and R&D information flow: is there a need for 'firewalls'?
by Milliou, Chrysovalantou
- 45-65 High-tech clusters, technology spillovers, and trade secret laws
by Fosfuri, Andrea & Ronde, Thomas
- 67-81 Technological externalities and economies of vertical integration in the electric utility industry
by Nemoto, Jiro & Goto, Mika
- 83-100 Wages and productivity growth in a dynamic monopoly
by Bester, Helmut & Petrakis, Emmanuel
- 101-134 A structural econometric model of price discrimination in the French mortgage lending industry
by Gary-Bobo, Robert J. & Larribeau, Sophie
- 135-145 Cost of delay and endogenous price leadership
by Pastine, Ivan & Pastine, Tuvana
2003, Volume 21, Issue 10
- 1435-1459 Competitive pressure and economic integration: an illustration for Spain, 1983-1996
by Siotis, Georges
- 1461-1487 The independent submarkets model: an application to the Spanish retail banking market
by de Juan, Rebeca
- 1489-1526 A new methodology linking concentration dynamics to current and steady-state profits:Examining Korean industrial policy during take-off
by Jeong, Kap-Young & Masson, Robert T.
- 1527-1556 Testing dynamic oligopolistic interaction: evidence from the semiconductor industry
by Zulehner, Christine
- 1557-1569 Low price equilibrium in multi-unit auctions: the GSM spectrum auction in Germany
by Grimm, Veronika & Riedel, Frank & Wolfstetter, Elmar
- 1571-1589 Efficiency outcomes of market concentration and managed care
by Sari, Nazmi
- 1591-1600 Horizontal mergers, entry, and efficiency defences
by Spector, David
- 1601-1622 Preemptive mergers under spatial competition
by Brito, Duarte
- 1623-1642 Monopoly, competition and information acquisition
by Dimitrova, Magdalena & Schlee, Edward E.
2003, Volume 21, Issue 9
- 1217-1225 The economics of intellectual property at universities: an overview of the special issue
by Link, Albert N. & Scott, John T. & Siegel, Donald S.
- 1227-1253 The anchor tenant hypothesis: exploring the role of large, local, R&D-intensive firms in regional innovation systems
by Agrawal, Ajay & Cockburn, Iain
- 1255-1270 Assessing spillovers from universities to firms: evidence from French firm-level data
by Monjon, Stephanie & Waelbroeck, Patrick
- 1271-1300 Disclosure and licensing of University inventions: 'The best we can do with the s**t we get to work with'
by Jensen, Richard A. & Thursby, Jerry G. & Thursby, Marie C.
- 1301-1322 Optimal incentives for income-generation in universities: the rule of thumb for the Compton tax
by Beath, John & Owen, Robert F. & Poyago-Theotoky, Joanna & Ulph, David