frontier oil , begun in 1949 as wainoco oil , was a u.s. energy company .

its headquarters were located in houston , tx , and its subsidiary company , frontier refining & marketing , inc. , is located in denver , co . frontier 's primary products were gasoline , diesel , and asphalt , and were marketed in the rocky mountain and plains states .

frontier oil owned refineries in cheyenne , wy and el dorado , ks .

the cheyenne refinery has a capacity of 52,000 barrels per day ( 8,300 m ³ / d ) ( bpd ) and the el dorado refinery has a capacity of 110,000 bbl/d ( 17,000 m ³ / d ) .

on november 7 , 2007 , frontier announced that the third quarter of 2007 had been the most profitable in the company 's history .

they reported a total income of us $ 137,200,000 for the quarter , and $ 432,700,000 for the year to that point .

frontier merged with holly corporation effective as of july 1 , 2011 to form hollyfrontier corporation .

frontier oil

assist in oil inventory and control . maintain oil quality and safe handling procedures . western frontier services has a current opening for a packaging lead . . .
frontier tank lines , inc . * . crude oil driving experience preferred . drivers perform basic driving functions in operating a crude oil product transport truck , . . .
reyes said drilling at sc 50 coincided with the steep drop of oil prices so frontier oil wanted to negotiate lower rates but the drilling rig contractor opted to terminate the contract .
on frontier oil’s request , this was denied by the doe which ruled that the contract effectively expired in march 2015 .
western frontier services has a current opening for an oil refining lead position based at our grandview , wa headquarters . . . .
frontier oil limited ( fol ) is an indigenous oil and gas production and development company with a proven track record of developing and bringing into production both crude oil and non - associated gas ( nag ) from the uquo marginal field . the company was formed in 2001 to participate in the 2003 federal government of nigeria marginal field programme through which frontier oil acquired the uquo marginal field located in oml13 , onshore akwa ibom state .
laboratory environment , laboratory equipment , extracted oil , work orders . western frontier services has a current opening for an extraction second position . . .
regularly exposed to fuel , oil , and other chemicals . perform minor equipment maintenance inspections such as greasing , checking oil and fluids . . . .
“frontier oil contested the doe’s position and engaged the doe in discussions aimed at a mutually acceptable resolution of the issue , ” trans - asia said .
regularly exposed to fuel , oil , and other chemicals . perform minor equipment maintenance inspections such as greasing , checking oil , transmission fluid and . . .
regularly exposed to fuel , oil , and other chemicals . operate distributor truck in the loading and off - loading of hot oil materials . . . .
frontier tank lines , inc . has an immediate opening for crude oil truck driversworking out of the _ san antonio _ * , tx location . . . .
regularly exposed to fuel , oil , and other chemicals . honesty , pride , respect–these are the values the pioneers of the frontier west lived by . . . .
what tips or advice would you give to someone interviewing at frontier t . . .
view all frontier tank lines , inc . jobs in midland , tx - midland jobs
information on trans - asia petroleum’s annual report showed frontier oil earlier applied for force majeure after drilling contractor umw offshore drilling sdn . of malaysia unilaterally terminated its rig contract .
“they ( frontier oil ) are appealing because the doe ( department of energy ) wants to terminate the contract , ” trans - asia petroleum executive vice president raymundo reyes said .
frontier tank lines , inc . questions about work , benefits , interviews and hiring process :
frontier tank lines provides fuel transportation services throughout texas , as well as four additional states .
view all frontier tank lines , inc . jobs in san antonio , tx - san antonio jobs
manila , philippines – frontier oil corp . is seeking a two - year moratorium on its obligations under service contract 50 in north palawan , trans - asia petroleum corp . said in its annual report .
holly backed out of the deal , then frontier sued holly for breach of contract . holly countersued , claiming frontier hadn ' t been straight about its potential for legal liabilities . following a 2005 trial the court found that frontier had breached the merger agreement . in 2008 most of the beverly hills oilfield class action complaints against frontier were dismissed and frontier reached a $ 6 . 3 million settlement with the rest of the claimants . in my 2008 profile of frontier , then - chief executive james gibbs said at the time that although holly would still make a great partner , there was too much bad blood for a marriage .
in accordance with the terms of the merger , frontier shareholders received 0 . 4811 holly shares for each share of frontier common stock they owned at closing . the combined entity will begin trading today under the symbol hfc .
our vision is to become one of the leading african indigenous oil and gas exploration and production companies by 2020 .
frontier oil has been planning an initial public offering ( ipo ) since 2013 but has decided to withdraw its plans to go public in 2014 to wait for more favorable market conditions as it explores alternative listing possibility in another stock exchange .
today holly corp . and frontier oil announced a $ 7 billion merger of equals , creating a strong refining operation with a geographic niche in the southwest and rocky mountain states with five refineries and more than 440 , 000 bpd of processing capacity .
sc 50 contains the calauit field , which is estimated to contain 10 million to 13 . 2 million barrels of oil .
founded in 1994 , frontier is proud to be known as a company “founded by heavy equipment users , for heavy equipment users . ”
this deal was a long time coming . holly and frontier first announced a merger back in 2003 . but holly got cold feet with tort lawyers led by erin brockovich and sidekick edward masry rounded up 800 plaintiffs and filed a class action suit against frontier , alleging that a subsidiary ' s oilfield under beverly hills high school was causing cancer .
old wounds heal . both holly ' s and frontier ' s longtime chairmen lamar norsworthy and jim gibbs have handed control to a the next generation of matt clifton ( holly ) and mike jennings ( frontier ) . clifton will chair the new company , to be called hollyfrontier while jennings will be ceo . holly shareholders will end up with 51 % of the newco .
trans - asia petroleum , a subsidiary of trans - asia oil and energy development corp . ( soon to be renamed phinma energy corp . ) , owns a 10 percent participating interest in sc 50 .
our mission is to deliver oil and gas fields profitably and responsibly for the benefit of all stakeholders , using cost effective technology and innovative solutions , motivated and talented staff , best in class hsse and corporate governance practices .
fol , working with its financial and technical partner , has successfully brought the formerly stranded uquo marginal field into production and , in doing so , created a brand new gas development , supply and distribution infrastructure in the south east niger - delta . in addition , fol is the operator of a joint venture operating a crude oil evacuation and delivery infrastructure from 3 marginal fields located in omls 13 & 14 to the exxon mobil qua - iboe crude oil terminal .
hollyfrontier corporation , which has a refining capacity in excess of 440 , 000 barrels - per - day ( bpd ) across five refineries , serves the niche mid - continent , rocky mountain and southwestern refining markets and has access to growing regional domestic and canadian crude oil supplies .
frontier oil limited ( fol ) is a wholly owned nigerian e & p company formed in 2001 and awarded the uquo marginal field in february 2003 by the department of petroleum resources ( dpr ) as part of the federal government of nigeria ' s marginal field programme . fol is the operator of the uquo marginal field which it is currently developing with its joint venture partner . fol aims to become the leading indigenous independent non - associated gas producer by the end of 2015 and a leading indigenous e & p company in the west africa sub region by 2020 .
fol’s experience , as operator of the uquo marginal field , spans the entire hydrocarbon value chain , from seismic acquisition all the way through to production of crude oil and non - associated natural gas . core activities include : the development and effective deployment of quality , health , safety , security and environmental ( qhsse ) processes and systems ; judicious application of industry and national codes and standards ; adherence to regulatory processes and compliance with regulatory requirements ; effective management of third - party service provider relationships ; development of a robust and fully functional best–in - class community relations / community development program with the uquo marginal field’s host communities , amongst others .
the following is a
safe harbor
statement under the private securities litigation reform act of 1995 : the statements in this press release relating to matters that are not historical facts are
forward - looking statements
based on management ' s beliefs and assumptions using currently available information and expectations as of the date hereof , are not guarantees of future performance and involve certain risks and uncertainties , including those contained in our filings with the securities and exchange commission . although we believe that the expectations reflected in these forward - looking statements are reasonable , we cannot assure you that our expectations will prove correct . therefore , actual outcomes and results could materially differ from what is expressed , implied or forecasted in such statements . any differences could be caused by a number of factors , including , but not limited to , risks and uncertainties with respect to the actions of actual or potential competitive suppliers of refined petroleum products in the company ' s markets , the demand for and supply of crude oil and refined products , the spread between market prices for refined products and market prices for crude oil , the possibility of constraints on the transportation of refined products , the possibility of inefficiencies , curtailments or shutdowns in refinery operations or pipelines , effects of governmental and environmental regulations and policies , the availability and cost of financing to the company , the effectiveness of the company ' s capital investments and marketing strategies , the company ' s efficiency in carrying out construction projects , the ability of the company to acquire refined product operations or pipeline and terminal operations on acceptable terms and to integrate any future acquired operations , the possibility of terrorist attacks and the consequences of any such attacks , general economic conditions , risks and uncertainties with respect to our ability to realize fully or at all the anticipated benefits of the merger between holly and frontier and other financial , operational and legal risks and uncertainties detailed from time to time in the company ' s securities and exchange commission filings . the forward - looking statements speak only as of the date made and , other than as required by law , we undertake no obligation to publicly update or revise any forward - looking statements , whether as a result of new information , future events or otherwise .
combines two leading independent refiners to create the most profitable ( on a per barrel basis ) independent refiner in the u . s .
, president and chief executive officer , said :
hollyfrontier has significant refining capacity in fast growing , traditionally high demand areas and will take advantage of diversified revenue sources , expanded infrastructure and increased scale of assets . hollyfrontier is committed to safe , reliable and environmentally responsible operations , and to outstanding corporate citizenship . the completion of this merger is a significant event for our shareholders , who will benefit from the synergies of this combination and from the significant growth potential that we anticipate as one of the largest independent refiners in the u . s . we are excited to move forward and to deliver on the promise of this transaction to create value for shareholders .
, is an independent petroleum refiner and marketer that produces high value light products such as gasoline , diesel fuel , jet fuel and other specialty products . hollyfrontier operates through its subsidiaries a 100 , 000 barrels per stream day (
bpsd
) refinery located in
. hollyfrontier markets its refined products principally in the southwest u . s . , the
and in other neighboring plains states . a subsidiary of hollyfrontier also owns a 34 % interest ( including the general partner interest ) in holly energy partners , l . p .
holly has generated a lot of value since then , spinning off its pipeline assets into a master limited partnership , and acquiring two refineries in tulsa for a song and combining them .
both companies suffered when gasoline demand and refining margins collapsed in late 2008 and the adoption of carbon - cap - and - trade seemed imminent . but profits are up again , and shares of both companies have more than doubled in the past year . so how did holly get over the bad blood to make a deal now ?
and what ' s next for the new refining combo ? if they think they can get it past the federal trade commission , look for hollyfrontier to acquire western refining within a couple years .
please fill in the details above and click ' send message ' . your details will not be disclosed to anyone and is required for security and validation purposes only .
lagos office - no 9c joseph adu street , oniru estate , victoria island extension , lagos state , nigeria . eket office - no 7 imeh johnson street , opposite , exxonmobil airstrip , eket , akwa - ibom state , nigeria .
fol is a professionally managed and committed indigenous operator with ambitions of becoming one of the leading indigenous e & p companies in nigeria and a mid - size regional player .
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our products will perform to your satisfaction , or we will replace them , dollar for dollar , with any other product in our line , no questions asked .
reduce your downtime , maintenance requirements and overall repair and replacement costs increasing the useful life of your machinery .
our custom lubricants are formulated from the finest base stocks available , coupled with the most advanced additive technology on the market today .
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through onsite problem solving and the application of innovative technologies , we maximize production , optimize water use and overcome complex challenges in the . . .
through on - site problem solving and innovative technologies , our team provides solutions that help energy customers overcome complex challenges in the world’s . . .
how long does it take to get hired from start to finish ? what are the st . . .
please note that all salary figures are approximations based upon third party submissions to indeed . these figures are given to the indeed users for the purpose of generalized comparison only . minimum wage may differ by jurisdiction and you should consult the employer for actual salary figures .
umw offshore was tapped in september 2014 in a $ 20 - million deal .
“it’s under arbitration in singapore . there will be a resolution soon , ” he said .
its other project is sc 52 in cagayan valley , which is estimated to contain contingent gas resource of as much as 231 . 91 billion cubic feet .
i watched the livestream of a pre - sona forum last friday where the infrastructure secretaries presented their vision .
world war i , described as the “war to end all wars , ” was triggered by the assassination of archduke franz ferdinand of austria on june 28 , 1914 .
metro pacific investments corp . unit nlex corp . plans to start mobilizing for the construction of the north luzon expressway - south luzon expressway connector road project by the fourth quarter this year and begin . . .
the department of information and communications technology ( dict ) is prepared to fight for its preferred selection method . . .
investment promotion agency philippine economic zone authority ( peza ) remains upbeat that investments in economic zones this . . .
the national government plans to increase next year its borrowings to p1 . 19 trillion to finance possible higher fiscal deficit , . . .
the prevailing weakness of the peso versus the dollar should not be a cause for concern as the economy continues to benefit . . .
anz research said the philippines may sustain a robust economic growth this year that has led to rising inflation as well . . .
the bureau of the treasury yesterday made a full award of the 91 - day and 182 - day treasury bills , but decided to partially . . .
the market ended flat on the first trading day of the week amid sluggish trading and thin volume .
lucas matthysse’s trainer has fired warning shots against manny pacquiao six days ahead of the biggest boxing event . . .
take it from the man who worked two fights opposite wba welterweight champion lucas matthysse of argentina .
president rodrigo duterte will meet with newly elected prime minister mahathir bin mohamad next week to discuss terrorism . . .
wba welterweight champion lucas matthysse will spend the rest of fight week maintaining the optimum weight for his clash with . . .
las vegas - based international matchmaker sean gibbons is convinced manny pacquiao will dethrone wba welterweight champion . . .
lucas matthysse’s trainer has fired warning shots against manny pacquiao six days ahead of the biggest boxing event in this country since 1975 .
president rodrigo duterte will meet with newly elected prime minister mahathir bin mohamad next week to discuss terrorism and rebellion .
wba welterweight champion lucas matthysse will spend the rest of fight week maintaining the optimum weight for his clash with manny pacquiao at the axiata arena in kuala lumpur , malaysia on sunday .
las vegas - based international matchmaker sean gibbons is convinced manny pacquiao will dethrone wba welterweight champion lucas matthysse of argentina in kuala lumpur on july 15 either by a clear decision or a late stoppage .
with the tongue we praise our lord and father , and with it we curse human beings , who have been made in god’s likeness . — james 3 : 9
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knowledge spillover is an exchange of ideas among individuals .

in knowledge management economics , knowledge spillovers are non-rival knowledge market costs incurred by a party not agreeing to assume the costs that has a spillover effect of stimulating technological improvements in a neighbor through one 's own innovation .

such innovations often come from specialization within an industry .

a recent , general example of a knowledge spillover could be the collective growth associated with the research and development of online social networking tools like facebook , youtube , and twitter .

such tools have not only created a positive feedback loop , and a host of originally unintended benefits for their users , but have also created an explosion of new software , programming platforms , and conceptual breakthroughs that have perpetuated the development of the industry as a whole .

the advent of online marketplaces , the utilization of user profiles , the widespread democratization of information , and the interconnectivity between tools within the industry have all been products of each tool ’s individual developments .

these developments have since spread outside the industry into the mainstream media as news and entertainment firms have developed their own market feedback applications within the tools themselves , and their own versions of online networking tools ( e.g. cnn ’s ireport ) .

there are two kinds of knowledge spillovers : internal and external .

internal knowledge spillover occurs if there is a positive impact of knowledge between individuals within an organization that produces goods and/or services .

an external knowledge spillover occurs when the positive impact of knowledge is between individuals without or outside of a production organization .

marshall-arrow-romer ( mar ) spillovers , porter spillovers and jacobs spillovers are three types of spillovers .

knowledge spillover

our results identify further benefits for the originating firm that may be gained from knowledge spillover .
with this selection of previously published articles , professor acs provides a guided tour to the leading ideas in knowledge spillover theory . the volume not only includes some of the foundational writings on the use of knowledge in business and industry , but also brings us right up to date with some seminal articles illustrating the latest thinking on entrepreneurship , the knowledge spillover theory and the knowledge filter .
‘the knowledge spillover theory of entrepreneurship stands as a welcome contribution to entrepreneurship and management literature . ’ – james cunningham , journal of entrepreneurship
the complementary research designs at both firm level and patent level offer comprehensive view on firm explorative behavior under the influence of their knowledge spillover recipients .
with this selection of previously published articles , professor acs provides a guided tour to the leading ideas in knowledge spillover theory . the volume not only includes some of the foundational writings on the use of knowledge in business and industry , but also brings us right up to date with some seminal articles illustrating the latest thinking on entrepreneurship , the knowledge spillover theory and the knowledge filter . professor acs has written a new , authoritative introduction , which provides a comprehensive overview and informative discussion of the subject .
acs , z . j . , audretsch , d . b . , braunerhjelm , p . , & carlsson , b . 2009 . the knowledge spillover theory of entrepreneurship .
we suggest that a possible answer may come from the field of economics , and the particular phenomenon known as a “jacobs spillover . ” simply put , this is the effect produced by proximities of different businesses , as they invariably exchange knowledge and creative ideas , and the knowledge “spillover” of one enterprise becomes the resource for another . for jacobs , this was an inherent benefit of cities , and specifically , of the interactions afforded by urban adjacencies .
we contribute to the literature on exploration by identifying a source of knowledge that firms may more easily explore .
abstract : this paper calls attention on the effects of the economic properties of knowledge on its derived demand , an issue that has not received enough attention in the literature . the results of the analysis suggests that , because of the idiosyncratic – arrovian – properties of knowledge , a chain of effects takes place : ( i ) in downstream markets the price of goods that have been produced using knowledge as an intermediate good , falls , ( ii ) consequently the derived demand in upstream knowledge markets – both within corporations and by them to knowledge - intensive business services – has a lower position , and ( iii ) the price of knowledge is lower than it should be were knowledge a standard good traded in competitive markets , ( iv ) with negative consequences in terms of adverse selection of large scale high quality research projects , but ( v ) possible compensating effects stemming from the use of knowledge spillovers to generate cheaper knowledge . such results have important implications for economic policy discussions and decisions .
knowledge spillover occurs when recipient firms combine the knowledge of an originating firm with other knowledge . when recipient firms combine the originating firm ' s knowledge with knowledge that is unfamiliar to the originating firm , the recipient firms potentially provide insight to the originating firm on the viability of exploring such knowledge . by mimicking its recipient firms , the originating firm reduces the challenge and uncertainty of exploring unfamiliar knowledge domains . we examine the exploration activities of 87 telecommunications equipment manufacturers over a ten - year time period . we argue that those firms that operate in competitive and dynamic market environments promoting conservative risk - taking behavior will value such uncertainty reduction more highly and thus rely to a greater extent on their recipient firms for guidance on where to explore for new expertise . in contrast , firms in high - growth market environments are more likely to look beyond the activities of recipient firms when exploring new technological domains and rely less on mimicking their recipient firms .
it is well understood that the non - rival nature of knowledge as a productive asset creates the possibility of
knowledge spillovers ,
whereby investments in knowledge creation by one party produce external benefits by facilitating innovation by other parties . at least since zvi griliches ' seminal paper on measuring the contributions of r & d to economic growth ( 1979 ) , economists have been attempting to quantify the extent and impact of knowledge spillovers . one line of research of this type has utilized patent citations to identify a
paper trail
that may be associated with knowledge flows between firms .
acs z . j . , audretsch d . b . ( 2010 ) knowledge spillover entrepreneurship . in : acs z . , audretsch d . ( eds ) handbook of entrepreneurship research . international handbook series on entrepreneurship , vol 5 . springer , new york , ny
stepan ,
in 1890 the english economist alfred marshall developed a theory of knowledge spillovers
. see more here : urltoken
the results suggest a
half - full cup
with respect to the validity of patent citations as indicators of knowledge spillovers . taking the responses at face value , the likelihood of knowledge spillover conditional on the observation of a patent citation is significantly greater ( in both the statistical and quantitative senses ) than the unconditional likelihood . nonetheless , a large fraction of citations , perhaps something like one half , do not correspond to any apparent spillover . we believe that these results are consistent with the notion of citations as a noisy signal of the presence of spillovers . this implies that aggregate citation flows can be used as proxies for knowledge spillover intensity , for example between categories of organizations or between countries . further work is needed , however , to refine our understanding of the mechanisms by which these flows move and the relationship of those mechanisms to the citation process .
assuming that these responses can be taken at face value , they suggest that a significant , but not overwhelming , fraction of the
links
indicated by a patent citation correspond to some kind of spillover . across the different aspects captured by each of these questions , typically one - quarter of the responses correspond to a fairly clear spillover ; perhaps one - half of the answers indicate no spillover , and the remaining quarter indicate some possibility of a spillover . it is also clear that addition of citations by the inventor ' s patent lawyer or the patent examiner is the primary reason for citations to patents unknown to the inventor .
jaffe , adam b ; trajtenberg , manuel ; and henderson , rebecca .
geographic localization of knowledge spillovers as evidenced by patent citations .
anselin , l . , varga , a . , & acs , z . j . 2000 . geographic and sectoral characteristics of academic knowledge externalities .
jaffe , a . , trajtenberg , m . , & henderson , r . 1993 . geography , location of knowledge spillovers as evidence of patent citations .
very little of this research has attempted to determine the modes or mechanisms of communication that actually permit knowledge to flow . further , most of the work has simply assumed that citations or other proxies are sufficiently correlated with knowledge flows to allow statistical analysis of the proxies to be informative regarding the underlying phenomenon of interest .
a . marshall was definitely the first , but i would recommend looking at the early publications of z . j . acs & d . b . audretsch , as they introduce the knowledge spillover theory of entrepreneurship . also i believe the following publication will be of your interest : jaffe a . b . , trajtenberg m . , henderson r . ( 1993 ) , geographic localization of knowledge spillovers as evidenced by patent citations . quarterly journal of economics . 108 ( 3 ) , pp . 577 - 598 .
a third question relates to the mode of knowledge spillover . even for the
true
citations , only about 18 % indicated that they had had either direct communication or had been exposed to some kind of presentation or demonstration of the cited invention . another 18 % indicated that they learned through
word of mouth
or had read the patent document itself .
acs , z . j . , anselin l . , & varga , a . 2002 . patents and innovation counts as measures of regional production of new knowledge .
agarwal , r . , audretsch , d . , & sarkar , m . ( 2007 ) . the process of creative construction : knowledge spillovers , entrepreneurship and economic growth .
carlsson , b . , acs , z . , audretch , d . , & braunerhjelm , p . 2009 . knowledge creation , entrepreneurship and economic growth : a historical review .
it seems likely that all of these spillovers might in fact have additional interactive spillover charactertistics – that i might , for example , also find a new job near my home on the way to another destination , and then share a creative bit of knowledge with a colleague , and then perhaps purchase some wood pellets at the local furniture store , and so on . that is , such spillovers might in fact form a kind of “spillover network” that has additional synergies . as this network grows within the city , its capacity to generate additional unforeseen spillovers also grows exponentially with its number of nodes , following the compounding power of networks .
braunerhjelm , p . , acs , z . , audretsch , d . b . , & carlsson , b . 2010 . the missing link : the knowledge filter and endogenous growth .
by conceptualizing exploration behavior within the realm of managerial risk - taking , we show how firms can explore new knowledge domains in a way that reconciles the tension of taking on additional risk in an already uncertain environment .
overall , the results confirm that citations can be interpreted as providing a ( noisy ) signal of spillovers . the difference in spillover score between the citations and placebos is quantitatively and statistically significant . the other variables generally have plausible and often significant effects . overall , the spillover score is higher if the
cited
patent is more recent . interestingly , analyses that separate the true citations from the
placebos
show that this combined effect mixes a significantly positive effect for the citations with a significantly negative effect for the placebos . for the citations , this is consistent with more recent patents being more useful , and older citations being more likely to be non - spillovers included by the lawyer or examiner . it could also reflect the possibility that the inventor ' s memory of actual communication is better with respect to more recent technology . conversely , for the placebos , the spillover index is
abstract : this paper explores the role of immigrant employees for a firm ' s capability to absorb international knowledge . using matched employer - employee data from denmark for the years 1999 to 2009 , we are able to show that non - danish employees from technological advanced countries contribute significantly to firm ' s economic output through their ability to access international knowledge . the empirical results suggest that the immigrants ' impact increases if they come from technological advanced countries , have a high educational level , and are employed in high - skilled positions . however , the latter does not hold for immigrant managers .
abstract : the relative importance of intra - industry or inter - industry knowledge spillovers for the growth of cities remains an open question . using a unique data set on the growth of 109 british cities during 1951–1991 , we find evidence suggesting that the most important knowledge spillovers occur between rather than within industries , which is consistent with jacobs ( 196910 . jacobs , j . 1969 . the economy of cities , new york : vintage books . view all references , 198511 . jacobs , j . 1985 . cities and the wealth of nations , new york : vintage books . view all references ) .
a spillover is also an example of a process in which the output of one system becomes the input of another system , which is then able to transform it in some important way . a close analogy is the “metabolic pathways” of biological systems . such processes typically do not operate in isolation , but as part of complex “metabolic networks . ” this allows a complex interactive sequence of processing , with the efficient assembly of very complex outputs as a result .
nor is the jacobs spillover the only such externality that seems to be operating in cities . we may also consider the physical proximity of the consumption of resources , which may account for similar kinds of urban synergies . for example , stockholm and other cities use “combined heat and power” to utilize the waste heat from power generation to heat homes . many businesses use the waste output of one process as the input of another – for example , wood manufacturing businesses may use waste wood chips as a fuel source .
this paper reports on a preliminary attempt to improve this situation . the idea for this survey came from r & d managers whom we were interviewing to test whether the picture of knowledge flows produced by patent citations was consistent with the managers ' impressions . one of these managers commented that he couldn ' t let us talk to the scientists who worked for him , but that he couldn ' t stop us from contacting them via the postal address that appears on their issued patents .
in order to test formally whether the respondents ' answers relating to citations are different from those for the placebos , we constructed a composite spillover index for each
cited
patent , using the answers to all 4 questions . this index was constructed by consolidating the possible answers to each question to produce a score of 0 , 1 or 2 , and then adding these scores across the 4 questions . we then undertook an ordered probit analysis of this score , using as regressors variables that would seem likely to foster communication between the cited and citing inventors , variables that might foster the inventor ' s
many of the important concepts in the economics of technological change are fundamentally unobservable . we routinely rely , therefore , on proxies or indicators for the concepts of interest . often , our only test of the validity of these measures is the extent to which the proxies are correlated in the way that our theory says that their underlying concepts should be . in this paper , we provide an additional kind of evidence about the unobservable process of knowledge transfer , and the relationship of patent citations to that process .
this , i suggest , indicates a promising research agenda for further investigation . the tangible goal might be to develop a “spillover network” or “metabolic network” model that might explain some of the more significant synergies and metabolic network - like aspects of urban systems , with the capacity to make differential comparisons based upon morphology . such a model would ideally be capable of making useful predictions about choices in urban and infrastructure design , and urban and economic policy . such a model might also facilitate the ability to monetize the currently unpaid costs of unsustainable urban development , and the long - term economic benefits of more sustainable development .
but the key observation of interest to us is that the spillover is an output of one system , which becomes an input into another – and this “virtuous circle” has a synergetic effect , increasing the economic efficiency of the city . this seems to be the case particularly when multiple variables are involved , and the synergies can compound through a kind of network effect . for glaeser et al . ( 1992 , 2009 ) , this synergy from spatial proximity represents a core advantage of cities , and may even explain why cities are economically attractive places at all . this was also a theme of jacobs’ own book the economy of cities ( 1969 ) .
the jacobs spillover is one form of an “externality” – an effect of an economic transaction that is not agreed to by the parties of that transaction , or factored into the accounting of such an economic transaction , but does have a consequence for one or more of the parties , whether positive or negative . an example of a large - scale negative externality is the depletion of resources like oil , or the accumulation of greenhouse gases that cause climate change . these phenomena will eventually impose a real cost , whether or not it is factored into the transactions . ( thus , one promising line of research is in ways to “monetize” these externalities , so that they can provide more direct economic benefits or penalties , and thus work to incentivize the sustainable use of resources . )
there is another interesting question to explore . why is it that some suburban areas seem to have comparable levels of economic activity from spillovers , without the close proximity of people in cities ? why do they also have high emissions rates , which might suggest here is no correlation with economic spillovers as we suggest here ? we hypothesize that this is because they are reproducing the conditions of proximity that facilitate spillover within cities , but doing so artificially , through relatively high - resource consuming activities – particularly , they are driving many trips of long distances in single - occupant automobiles . they are also performing other high - consumption , low - efficiency activities – living in isolated large homes , consuming poor - durability goods , living a “drive - through” lifestyle . they are able to maintain the economic spillovers after a fashion , using automobiles , cell phone contact , email , and other more artificial forms of contact – but only with a lifestyle that requires prodigious ( and very likely unsustainable , it appears ) inputs of resources .
in addition to the use of individual citation
links
as possible evidence of knowledge flow , a number of authors have utilized the total number of citations received by a patent as an indicator of the relative significance of patents . both our citing and cited inventor surveys asked the inventors to rate the
technological significance
and the
economic importance
of the inventions , and also asked whether the patent had been licensed and whether it had been commercialized . jaffe , trajtenberg and fogarty ( 2000 ) presents results of regressions of the log of total citations received on these indicators of importance . for this purpose , the citing and cited responses were combined into one dataset . in order to control for variations in citation practice by field and changes in propensity to cite and extent of truncation over time , all regressions include technology field and grant year dummy variables . in addition , based on the findings of jean lanjouw and mark schankerman ( 1999 ) , we also included the log of the number of claims made by each patent , to allow for the possibility that patents that consist of more claims are more highly cited .
the survey results suggest that communication between inventors is reasonably important , and that patent citations do provide an indication of communication , albeit one that also carries a fair amount of noise .
received by their patents from subsequent patents ( the
cited inventor
survey ) . for the
citing inventor survey , we asked the inventor a series of questions about the extent , timing and nature of communication that they had had with the inventors of three previous patents . two of these previous patents were patents that appeared among the citations made by the surveyed inventor ' s patent . the third previous patent was a
placebo
patent that was not cited by the surveyed inventor , but which was granted in the same patent class and year as one of the actually cited patents . in the survey questionnaire this placebo was not identified or distinguished in any way ; all three of the earlier patents were referred to as
cited patents .
cited inventors were also asked a series of questions about the economic and technological significance of their inventions .
citing survey , based on patents granted to these inventors in 1993 . we received 214 partial or complete responses to the
cited inventor survey , based on patents granted to these inventors between 1985 and 1993 .
we discuss here the responses to four questions asked of the citing inventors about their cited and
placebo
patents . one of the questions sought responses on a likert scale to a question regarding the overall degree of familiarity of the citing inventor with the cited invention . for the patents that were in fact cited , 28 % of the responses indicated a 4 or 5 on the likert scale , indicating a significantly high familiarity ; just under half of the respondents rated their familiarity at the low end of the scale . in contrast , over 80 % of the respondents rated their familiarity with the
placebo
patent at the lowest possible level .
when they learned about the
cited
invention . for the
true
citations , about 38 % of respondents indicated that they had learned about the cited invention either before or during the development of their own invention . about one - third indicated that they had learned about it after essentially completing their invention , including cases where they learned about it during the preparation of their own patent application . a little less than one - third indicated that , despite the presence of the patent citation , they had not learned about the cited invention before receiving our survey . this is not surprising , because citations to inventions unknown to the inventor can be generated by the inventor ' s patent attorney or the patent office examiner .
consistent with the answers regarding timing , almost 40 % indicated that it was the process of their own patent application that had caused them to learn of the previous invention .
the last question in this section , perhaps ambitiously , tried to get at the issue of the nature of assistance that the citing inventor may have received from the cited invention . respondents were given a set of choices that we thought possible , and also invited to
write in
their own responses . again , about 60 % of the respondents indicated some specific way in which they had benefited from the
cited
invention ; the single most common response was that the cited invention represented a concept that could be improved upon .
the
other
responses provided by the inventors also provide some insight into the nature of possible interactions . examples include :
the technology from patent 1 was incorporated in the product which used my invention .
the other patents gave credibility to our idea - they showed our ideas were ' feasible ' to the people not intimately involved in our idea .
remembering that communication occured , other controls , and a dummy variable for whether the score pertains to a
true
citation as opposed to a placebo . results of these analyses are presented in jaffe , trajtenberg and fogarty ( 2000 ) .
lower the more recent the
cited
invention . since these represent patents that were not , in fact , cited , there should not have been communication ; thus the negative coefficient for the placebos is consistent with the inventors ' giving more accurate answers with respect to more recent patents , and more often
mistakenly
indicating communication with respect to older patents .
we included the ( log of ) total citations received by the
cited
patent to control for the overall
importance
of that patent . it exhibits a positive effect , meaning that more important patents are perceived to have generated greater spillovers , whether because the spillovers are truly greater or simply more likely to be remembered by the respondent . similarly , cited patents whose inventors reside in the same state as the citing inventor are perceived to have generated greater spillovers . these two variables are
ought to be correlated with spillovers for the citations , but is uncorrelated with these things for the placebos .
the results provide some evidence that citations are correlated with significance or importance as perceived by the inventors themselves . each of the indicators is positively correlated with log citations , with the coefficients achieving t - statistics that vary from just below to just above 2 , depending on the question . there is no particular indication as to whether citations are more associated with technological versus economic significance . the claims variable is strongly significant , though its elasticity of about . 25 suggests strong diminishing returns to increasing the number of claims , as distinct from the constant returns relationship suggested by lanjouw and schankerman . if the claims variable is excluded from the regression , the effect of the perceived importance variable increases , suggesting that importance , as perceived by the inventor , reflects both the
size
of the patents as indicated by the number of claims , and the importance or significance of each of the claims .
griliches , zvi .
issues in assessing the contribution of r & d to productivity growth .
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ and michael s . fogarty .
report on a survey of inventors ,
national bureau of economic research ( cambridge ma ) working paper no . xxxx , february 2000 .
lanjouw , jean o . and schankerman , mark .
the quality of ideas : measuring innovation with multiple indicators .
national bureau of economic research ( cambridge ma ) working paper no . 7345 , september , 1999
brandeis university and nber , ms 021 , brandeis university , waltham ma 02454 - 9110 , usa , ajaffe @ brandeis . edu ; tel aviv university and nber , eitan berglas school of economics , tel - aviv university , tel - aviv 69978 , israel , manuel @ urltoken ; and case - western reserve university , center for regional economic issues , wickenden 311 , case - western reserve university , cleveland oh 44106 , usa , msf3 @ post . cwru . edu . we thank richard anderson for his help in editing and administering the survey , and melinda miller and margeret lister fernando for research assistance .
patent citations or references appear on the front page of a granted patent . they serve the legal function of identifying
prior art
upon which the current invention builds . for more detail , see jaffe , trajtenberg and rebecca henderson , 1993 .
ii the survey instruments were
pretested
on about 20 experienced inventors and the survey questions refined in response to their questions and comments . space limitations preclude a detailed description of the survey and survey samples . for these details , see jaffe , trajtenberg and fogarty ( 2000 ) .
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edited by zoltán j . ács , professor , london school of economics and political science and university professor , school of policy , government and international affairs , george mason university , us
35 articles , dating from 1945 to 2008 contributors include : p . aghion , k . j . arrow , w . j . baumol , r . henderson , a . jaffe , b . jovanovic , r . e . lucas , jr . , j . schumpeter , s . shane , l . zucker
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we highlight factors that influence how firms explore new technological domains , specifically how firms can gain insight from their recipient firms , rather than a firm ' s general propensity to exploration , or the choice between exploration and exploitation .
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hi , i need to analyse historical data about tai indexes for countries . i am interested in the period 1990 - 2017 , can someone tell me where i can . . .
dear experts , i am using stata command xtabond2 and system gmm for my very first project . according to arellano and bond ( 1991 ) , arellano and . . .
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i am trying to replicate the methods of other papers using fa which describe applying the factor scores to their data . i have a 7 point likert . . .
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one of the most frequently asked topics i come across is how to create simple scales from likert - scored items . apparently there are a lot of . . .
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just as the economy has been besieged by a wave of technological change that has left virtually no sector of the economy untouched , scientific understanding of the innovative process—that is , the manner by which firms innovate , and the impact such technological change has on enterprises and markets—has also undergone a revolution , which , although somewhat quieter , has been no less fundamental . well into the 1970s , a conventional wisdom about the nature of technological change generally pervaded . this conventional wisdom had been shaped largely by scholars such as alfred chandler ( 1977 ) , joseph schumpeter ( 1942 ) , and john kenneth galbraith ( 1956 ) who convinced a generation of scholars and policymakers that innovation and technological change lay in the domain of large corporations and that small business would fade away as the victim of its own inefficiencies .
these keywords were added by machine and not by the authors . this process is experimental and the keywords may be updated as the learning algorithm improves .
thanks go to al link for his thoughtful comments and insights as well as to the suggestions made by a number of other contributors to this volume .
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note : this is a working paper presented at the symposium “scaling in cities” at arizona state university , co - organized with the santa fe institute , university college london and the environmental structure research group ( sustasis foundation ) , in october 2011 .
among analysts of urban resource use , energy use and greenhouse gas emissions , one rather perplexing and tantalizing phenomenon has been widely recognized . across the globe , there is an enormous variation in the per - capita rates of consumption , but often without corresponding variations in income , standard of living , or other metrics of “quality of life . ” for example , the world resources institute ( 2009 ) reports a roughly six - fold increase in rates of co2 emissions per capita , comparing residents of stockholm , sweden , to residents of the united states as a whole ( including many suburban and rural communities ) . ( figure one . ) both populations enjoy a comparably high standard of living that is , if anything , higher in stockholm by most measurements .
some of this variation can perhaps be explained by cultural and geographic differences . but it is very hard indeed to explain such a wide variation with such factors alone . in addition , there are great variations even within countries , as the work of mckinsey & co . ( 2008 ) and the world resources institute ( 2009 ) show . the per - capita rate of co2 emissions in new york city is roughly one - third of the overall us rate , and the rate in stockholm is roughly one - half of sweden’s national rate .
urban morphologists , intrigued by this data , have looked for variations of morphology that might accont for the variations , such as density , urban distributions , and transportation system variations ( e . g . solutions research project , 2010 ) . but the magnitudes that are accounted for in these models are generally far lower than the actual variations observed , even when corrected for obvious variables like climate and income . it seems clear that many other factors contribute to the variation , including infrastructure efficiency and personal consumption patterns . even the identifiable elements , however , seem unable to explain the large magnitude that is observed .
what , then , can account for such a magnitude of variation ? it seems that there may be some other kind of mechanism or mechanisms that have not yet been recognized .
such resource “spillovers” seem to operate in other realms too . if my daily activities are grouped close together , i may use the same trip by streetcar to stop along the way to meet another need that i might otherwise accomplish with a separate trip . these “transit spillovers” might account for a significant part of transit reduction in urban areas , beyond simply reduced distances between destinations .
in ecological systems , we can see a corollary when the excess chemical output or “waste” of one system becomes the input or resource of another . when these processes are part of a larger ecological network , the productivity of the system in biological terms can be greatly accelerated , while the “waste” of the system – the outputs that are not re - used – can be greatly reduced , or even brought to essentially zero . this network of “spillovers” – that is , of outputs becoming inputs – therefore represents a dramatic increase in the “efficiency” of the system – its ability to achieve high states of order with low waste .
is a similar kind of process perhaps going on in cities ? can we use this model to understand and perhaps enhance the puzzling but remarkable resource efficiency of cities ? can we use it to confront the daunting problem of climate change , and , as suggested by the empirical observaitons , dramatically reduce the emissions of people within cities ? this problem takes on special relevance as we see new patterns of urbanization around the globe , and the indications are that these new urban areas will follow the us model of very high consumption of resources with high levels of waste , and very high emissions per capita – a disturbing implication for the prospects of catastrophic climate change .
one revolves around the subject of urban density , or persons per unit of land – a controversial and problematic topic to be sure . is urban density the only identifiable factor that affects this externality , or can we measure and model other factors ? what about certain patterns of spatial distribution – for example , of uses , or of street networks , or of transit modes ? what about jacobs’ own hypothesis that walkable street - based urbanism , with its close stitching of private and public realms , was a critical mode of human connection , not reproduced in other forms of transportation ?
another , more distant but ultimately most important line of inquiry is to explore strategies to exploit this phenomenon , assuming it can be substantiated . can planners use strategies of “self - organization” to catalyze the spontaneous growth of such urban “metabolic networks” ? can they be facilitated with economic tools , such as pricing signals and other mechanisms ? what is the role of “top - down” planning , such as the placement of initial elements of infrastructure and the like ? our hunch is that a mix of all these strategies could be powerful and effective .
glaeser , e . ( 1992 ) . “growth in cities . ” journal of political economy , vol . 100 .
glaeser , e . ( 2009 ) . “the wealth of cities : agglomeration economies and spatial equilibrium in the united states . ” national bureau of economic research .
jacobs , j . ( 1969 ) . the economy of cities . new york : random house .
mckinsey & company ( 2009 ) pathway to a low - carbon economy : version 3 of the global greenhouse gas abatement cost curve , p . 7 .
world resources institute ( 2009 ) co2 emissions per capita . accessed september 23 , 2011 at urltoken
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