dynamic interaction between markets for leasing and selling automobiles we develop a model of dynamic interactions between price variations in leasing and selling markets for automobiles our framework assumes a differential game between multiple bertrand type competing firms which offer differentiated products to forward looking agents empirical analysis of our model using monthly us data from 2002 to 2011 shows that variations in selling cash market prices lead rapidly dissipating changes of leasing market prices in the opposite direction we discuss the practical implications of these results by augmenting a standard leasing valuation formula the additional terms represent the leased asset value changes that can be expected on the basis of past variations in automobile selling market prices

fixed costs and long lived investments abstract fixed costs models are difficult to analyze because they feature non degenerate time varying distributions of capital across firms if investments are sufficiently long lived however then the cross sectional distribution of capital holdings has virtually no bearing on the equilibrium and the aggregate behavior of fixed cost models is essentially identical to neoclassical models the findings are due to a near infinite elasticity of investment timing for long lived investments a feature shared by fixed cost models and neoclassical models irrelevance results found in numerical studies of fixed cost models are not parametric special cases but instead are fundamental properties of models with long lived investment goods

the forward fiscal guidance puzzle and a resolution abstract the forward fiscal guidance puzzle pertains to new keynesian models when monetary policy is temporarily caught in a liquidity trap 1 expected future fiscal shocks have an unbelievably large effect on current inflation and 2 the effect on current inflation is larger the further out is the shock expected to occur we illustrate the problem analytically then we use blue chip inflation forecasts to argue that the effects on inflation expectations should be small and finally we analyze two potential resolutions to the puzzle the first is the fiscal theory of the price level in a calibrated model with price inertia investment and long term debt we show that the fiscal theory resolves the second aspect of the puzzle but certainly not the first in our preferred resolution we return to a ricardian fiscal policy and we assume that the probability of a return to the taylor rule depends on the rate of inflation the model s predictions are in line with the evidence from the blue chip forecasts this article is part of a special issue entitled fiscal and monetary policies

the transition to digital television digital tv this paper studies the role of economic policy for the transition from analogue to digital television with particular attention to the switch off of the analogue terrestrial signal the analogue signal cannot be credibly switched off until almost all viewers have migrated to digital due to the policy objective of universal access to television but before switch off only part of the population can be reached with the digital signal in addition those who are reached need to spend more to upgrade their reception equipment than after switch off because the capacity to increase the power of the digital signal will be made available only then after reviewing the competitive structure and the role of government intervention in television markets we present the early experience of a number of industrialized countries in the transition to digital television we then formulate a micro econometric model of digital television adoption by individual viewers the model is calibrated to uk data and simulated to predict the impact of government policies on the take up of digital television policy makers can affect the speed of take up of digital television by 1 controlling the quality of the signals and the content of public service broadcasters 2 intervening in the market for digital equipment with subsidies and 3 publicizing the conditions and date of switch off of the analogue signal we find that if the analogue terrestrial signal is switched off only when certain aggregate adoption targets are reached strategic delays may arise and expectations may affect the success of the switch off policy jerome adda and marco ottaviani

the quantitative analytics of the basic neomonetarist model this paper constructs a dynamic macroeconomic model with less than perfect price flexibility which has a classical side consistent with real business cycle theory augmented by investment adjustment costs increasing returns to scale and a new flexible formalization of imperfect competition something akin to the classical dichotomy is justified by a mode of approximation appropriate for a model in which one state variable adjusts quickly while another state variable adjusts slowly even with investment adjustment costs monetary expansions are found to raise the real interest rate the determinants of real rigidity and the macroeconomic rate of price adjustment are investigated copyright 1995 by ohio state university press

why and when does the gender gap reverse diversity goals and the pay premium for high potential women abundant research has documented a gender pay gap women earn less than men all else being equal against the backdrop of an overall female penalty we propose that the widespread adoption of dive

targeted transfers and the fiscal response to the great recession abstract between 2007 and 2009 government expenditures increased rapidly across the oecd countries while economic research on the impact of government purchases has flourished in the data most of the increase in expenditures was in government transfers after documenting this fact we argue that future research should focus on the positive impact of transfers towards this we present a model in which there is no representative agent and ricardian equivalence does not hold because of uncertainty imperfect credit markets and nominal rigidities targeted lump sum transfers are expansionary both because of a neoclassical wealth effect and because of a keynesian aggregate demand effect

dampened expectations in the phillips curve a note abstract dampened inflation expectations have a significant impact on the new keynesian phillips curve this dampening not only flattens the long run phillips curve but it can also lead to a bias in the estimation of its short run slope it also affects the response of a small nk model to demand shocks and affects the optimal monetary policy in particular the price targeting result of the ramsey policy is violated when there is dampening

a quantitative analysis of the used car market we quantitatively investigate the allocative and welfare effects of secondary markets for cars an important source of gains from trade in these markets is the heterogeneity in the willingness to pay for higher quality newer goods but transaction costs are an impediment to instantaneous trade calibration of the model successfully matches several aggregate features of the u s and french used car markets counterfactual analyses show that transaction costs have a large effect on volume of trade allocations and the primary market aggregate effects on consumer surplus and welfare are relatively small but the effect on lower valuation households can be large

is there a glass ceiling over europe exploring the gender pay gap across the wages distribution using harmonised data from the european union household panel we analyse gender pay gaps by sector across the wages distribution for ten countries we find that the mean gender pay gap in the raw data typically hides large variations in the gap across the wages distribution we use quantile regression qr techniques to control for the effects of individual and job characteristics at different points of the distribution and calculate the part of the gap attributable to differing returns between men and women we find that first gender pay gaps are typically bigger at the top of the wage distribution a finding that is consistent with the existence of glass ceilings for some countries gender pay gaps are also bigger at the bottom of the wage distribution a finding that is consistent with sticky floors third the gender pay gap is typically higher at the top than the bottom end of the wage distribution suggesting that glass ceilings are more prevalent than sticky floors and that these prevail in the majority of our countries fourth the gender pay gap differs significantly across the public and the private sector wages distribution for each of our eu countries

asset prices in a huggett economy this paper explores asset pricing in economies where there is no direct insurance against idiosyncratic risks but other assets can be used for self insurance subject to exogenously imposed borrowing limits we analyze an endowment economy based on huggett 1993 11 both with and without aggregate risk our main innovation is that we obtain full analytical tractability by studying the case with maximally tight borrowing constraints we illustrate by looking at riskless bonds equity and the term structure of interest rates and we show that the model can reproduce many features of observed asset prices when idiosyncratic risks are quantitatively reasonable

blind ambition the effects of social networks and institutional sex composition on the job search outcomes of elite coeducational and women s college graduates in this paper i develop a perspective on women s career attainment focused on how employers salary offers may be constructed based on their assumptions regarding women s access to comparative salary information therefore although the use of social networks in job search may enhance women s actual knowledge of prevailing wages i hypothesize that institutional characteristics that employers could assume to constrain women s networks and concomitant access to salary information will directly affect salary offers as well as moderating the influence of network ties on pay to test this perspective job search outcomes of women attending elite coeducational and women s colleges were examined regarding the number of offers obtained women who consulted with proportionally more male peer and employed adult male advice ties received significantly more job offers than women using fewer male advice contacts with regard to salary offers this study reveals an institutional sex composition effect women exiting single sex institutions i e women s colleges received significantly lower salary offers than women from coeducational schools even after accounting for human capital job characteristics and institutional reputation the effects of social networks on pay were moderated by institutional sex composition such that women exiting women s colleges received lower returns in the form of salary to their cross gender advice ties than did women from a matched coeducational institution implications of these results for theories of social capital and women s occupational attainment are discussed

fiscal policy and economic recovery the case of the 1936 veterans bonus conventional wisdom has it that in the 1930s scal policy did not work because it was not tried this paper shows that scal policy though inadvertent was tried in 1936 and a variety of evidence suggests that it worked a decit nanced veterans bonus provided 3 2 million world war i veterans with cash and bond payments totaling 2 percent of gdp the typical veteran received a payment equal to annual per capita personal income this paper uses time series and cross sectional data to identify the eects of the bonus i exploit four sources of quantitative evidence a detailed household consumption survey cross state and cross city regressions aggregate time series and a previously unused american legion survey of veterans the evidence paints a consistent picture in which veterans quickly spent the majority of their bonus spending was concentrated on cars and housing in particular narrative accounts support these quantitative results a simple calculation suggests that the bonus added 2 5 to 3 percentage points to 1936 gdp growth

household saving micro theories and micro facts in this survey we review the recent theoretical and empirical literature on household saving and consumption the discussion is structured around a list of motives for saving and how well the standard theory captures these motives we show that almost all of the motives for saving that have been suggested in the informal saving literature can be captured in the standard optimizing model particular attention is given to recent work on the precautionary motive and its implications for saving and consumption behavior we also discuss the behavioral or psychological approach that eschews the use of standard optimization techniques and focuses instead on direct consideration on saving we provide a section on facts who save and how much we then discuss informally the recent decline in the u s saving rate and whether the theory is of much use in understanding this and other changes in aggregate saving rates over time we do not find any convincing explanation for the change in saving rates we also discuss some analyses of saving behavior over the life cycle addressing such questions as whether households save enough for retirement and whether the consumption patterns of older households can be rationalized within a simple life cycle model we also review a great number of studies of the consumption euler equations based on our analysis of the studies cited we conclude that there is still mixed evidence that consumption is excessively sensitive to income we also examine in depth the recent empirical literature on the precautionary motive we conclude that although some households do seem to have a significant precautionary motive at some points in their life cycle this motive is not so strong empirically as some investigators suggest

consumer spending and the economic stimulus payments of 2008 abstract we measure the change in household spending caused by receipt of the economic stimulus payments of 2008 using questions added to the consumer expenditure survey and variation from the ran

bounds on elasticities with optimization frictions a synthesis of micro and macro evidence on labor supply how can price elasticities be identified when agents face optimization frictions such as adjustment costs or inattention i derive bounds on structural price elasticities that are a function of the observed effect of a price change on demand the size of the price change and the degree of frictions the degree of frictions is measured by the utility losses agents tolerate to deviate from the frictionless optimum the bounds imply that frictions affect intensive margin elasticities much more than extensive margin elasticities i apply these bounds to the literature on labor supply the utility costs of ignoring the tax changes used to identify intensive margin labor supply elasticities are typically less than 1 of earnings as a result small frictions can explain the differences between micro and macro elasticities extensive and intensive margin elasticities and other disparate findings pooling estimates from existing studies i estimate a hicksian labor supply elasticity of 0 33 on the intensive margin and 0 25 on the extensive margin after accounting for frictions

consumer durables and inertial behaviour estimation and aggregation of s s rules for automobile purchases the s s model originally introduced in the study of inventories see arrow et al 1951 scarf 1959 has recently received renewed attention both in the durable consumption and in the investment and labour demand literatures caballero 1993 for instance appeals to these type of models to explain the time series properties of durable expenditure and in particular the persistence or slow adjustment of such a variable in this paper i model the purchase behaviour of automobiles by u s households as an s s rule i estimate a flexible specification of such a rule using a large microeconomic data set and study some of the aggregate implications of this type of inertial behaviour the paper is one of the first attempts at estimating directly the parameters of an s s rule using micro data because of this some of the methodological issues concerning the specification and the estimation of s s rules are relevant for many potential applications furthermore the paper is one of the first to discuss and quantify the aggregate implications of an s s rule estimated on micro data in the presence of non convex transaction costs a full and consistent characterization of individual behaviour is very hard and typically requires strong restrictions grossman and laroque 1991 prove that an s s rule is optimal for a consumption and investment problem under very special circumstances some of their results were extended by eberly 1991 and beaulieu 1993a b eberly 1991 in particular has derived some closed form solutions for durable consumption in the presence of transaction costs while caballero and engel 1994 construct a model of investment where an s s rule is optimal the main problem with these theoretical results is that it is only possible to show optimality of s s rules under very stringent conditions in particular a necessary condition to derive them is that the optimization problem faced by an individual consumer can be reduced to a problem with a single state variable unfortunately as pointed out by bar ilan and blinder 1992 even simple generalizations are extremely difficult to analyse

do sales tax credits stimulate the automobile market in this paper we quantitatively investigate the effectiveness of a sales tax reduction in stimulating sales and profits of durable goods manufacturers our question is motivated by policy makers recent interest in helping ailing automobile manufacturers and in replacing a fleet of highly polluting vehicles president obama s economic stimulus plan for instance has directly targeted the primary market by including a sales tax credit on purchases of new cars and trucks in this paper we show that the benefit of reducing the sales tax measured by its effect on firms profits and sales greatly decreases with the product s durability the magnitude of our findings indicates that one must carefully account for durability and firms behavior when evaluating such policies our findings are robust when we vary key parameters of the market

equilibrium in a durable goods market with lumpy adjustment abstract durable goods are an important component of the business cycle equilibrium models of durable goods markets are made difficult by the lumpy nature of individual purchases we show that a straightforward approximation of the distribution of durable goods holdings gives rise to a tractable equilibrium model we analyze the case of competition as well as that of a monopoly producer

vintage specific driving restrictions local air pollution has led authorities in many cities around the world to impose limits on car use by means of driving restrictions or license plate bans by placing uniform restrictions on all cars many of these programs have created incentives for drivers to buy additional more polluting cars we study vintage specific restrictions which place heavy limits on older polluting vehicles and no limits on newer cleaner ones we use a novel model of the car market and results from santiago s 1992 program the earliest program to use vintage specific restrictions to show that such restrictions should be designed to work exclusively through the extensive margin type of car driven never through the intensive margin number of miles driven if so vintage restrictions can yield important welfare gains by moving the fleet composition toward cleaner cars comparing well to alternative instruments such as scrappage subsidies and pollution based registration fees

more or less a model and empirical evidence on preferences for under and overpayment in trade in transactions abstract trade in transactions typically involve an exchange of an old used version for a new or newer version of the product when consumers trade in their used model for a new model the firm faces the choice of paying the consumer a relatively low price for the used model and charging a commensurately low price for the new model or paying a relatively high price for the used model and charging a commensurately high price for the new model the extant literature suggests that consumers always prefer to be overpaid in trade in transactions because they disproportionately value the gain associated with the revenues from the sale of the used version of the product the authors draw from the prospect theory value function to develop a simple analytical model that identifies a condition under which this preference for overpayment is reversed their model predicts that even when faced with economically equivalent price formats consumers prefer to be overpaid when the ratio of the price of their used product

the power of forward guidance revisited in recent years central banks have increasingly turned to forward guidance as a central tool of monetary policy especially as interest rates around the world have hit the zero lower bound standard monetary models imply that far future forward guidance is extremely powerful promises about far future interest rates have huge effects on current economic outcomes and these effects grow with the horizon of the forward guidance we show that the power of forward guidance is highly sensitive to the assumption of complete markets if agents face uninsurable income risk and borrowing constraints a precautionary savings effect tempers their responses to changes in future interest rates as a consequence forward guidance has substantially less power to stimulate the economy in addition we show that the business cycle dynamics of our incomplete markets model differ substantially from its complete market counterpart this contrasts with the well known results of krusell and smith 1998 we present approximate representations that can easily be incorporated into standard business cycle models

permanent income liquidity and adjustments of automobile stocks evidence from panel data a recent article by bernanke 1984 tests the rational expectations permanent income hypothesis using panel data on automobile expenditures he finds no evidence refuting the hypothesis this paper incorporates a threshold adjustment process into bernanke s model estimations based on a subset of the data used by bernanke reveal evidence that resale market imperfections and credit market constraints have important effects on automobile expenditures

the aggregate implications of machine replacement theory and evidence the authors study an economy in which producers incur resource costs to replace depreciated machines the process of costly replacement and depreciation creates endogenous fluctuations in productivity employment and output of a single producer the authors explore the spillover effects of machine replacement on other sectors of the economy and provide conditions for synchronized machine replacement by multiple independent producers the implications of their model are generally consistent with observed monthly output employment and productivity fluctuations in automobile plants synchronization of retooling across plants within the auto industry is widespread so that the fluctuations observed at the plant level have aggregate implications copyright 1993 by american economic association

durable goods an explanation for their slow adjustment at the microeconomic level durable purchases are often discontinuous and relatively large this feature has the potential to explain why aggregate expenditure on durables responds only slowly relative to the frictionless permanent income model to wealth and other aggregate innovations in this paper i develop new results on the problem of dynamic aggregation of stochastically heterogeneous units which help to characterize the connection between microeconomic behavior and aggregate dynamics in the presence of nonconvex adjustment costs using these results and splitting postwar u s aggregate durable purchases into different subcategories and time periods i provide further support for the view that lumpy microeconomic purchases play an important role in explaining the time series behavior of aggregate expenditure on durable goods

investment crowding out firm level evidence from northern germany michalek j ciaian p and kancs d a investment crowding out firm level evidence from northern germany regional studies the main objective of this paper is to estimate the extent to which firm investment is substituted crowded out by investment support policies granted under the european union rural development programme rdp the empirical analyses employed the difference in difference propensity score matching approach which allows several important sources of bias to be addressed such as selection bias simultaneity bias and functional form misspecification from which many previous studies suffer using panel data of 1333 firms from the schleswig holstein region in germany it is found that the crowding out effect of the rdp is close to 100 implying that firms use public support to substitute for private investments furthermore no evidence was found that due to the rdp programme support firms would have brought forward their investments planned originally for a later period rejecting t

the effect of implementing trade in strategy on duopoly competition abstract we study a firm that makes new products in the first period and collects used products through trade in along with new product sale in the second period to conduct a convincing analysis we initially evaluate the problem in a duopoly situation in which one firm firm a implements trade in and the other one firm b does not we subsequently introduce the competitive environment in a two period planning horizon to identify thresholds that determine the trade in operations and then derive the equilibrium decisions of the resulting scenarios we characterize the optimal production quantities that are associated with parameter b the sum of used product salvage value and government subsidy in the nash equilibrium results indicate that adopting trade in could bring competitive advantage for firm a in terms of market share and profit if the new product sale is comparatively profitable then the trade in firm may forgo some of the collection margin by raising the trade in rebate and selling additional units to increase new product sale in the second period moreover the total collection quantity does not always increase with government subsidy we consequently expand the model to the case where both firms compete in trade in and derive the corresponding decision space of the duopoly firms finally we explore the effect of adopting trade in on consumer surplus and compare it in the two models

household expenditure and the income tax rebates of 2001 using questions expressly added to the consumer expenditure survey we estimate the change in consumption expenditures caused by the 2001 federal income tax rebates and test the permanent income hypothesis we exploit the unique randomized timing of rebate receipt across households households spent 20 to 40 percent of their rebates on nondurable goods during the three month period in which their rebates arrived and roughly two thirds of their rebates cumulatively during this period and the subsequent three month period the implied effects on aggregate consumption demand are substantial consistent with liquidity constraints responses are larger for households with low liquid wealth or low income

pegging the interest rate on bank reserves a resolution of new keynesian puzzles and paradoxes abstract introducing bank reserves or money into the basic new keynesian nk model offers a resolution of nk puzzles and paradoxes the resulting models deliver local equilibrium determinacy under an exogenous interest rate on reserves and an exogenous nominal stock of reserves even for an arbitrarily small monetary friction this leads to a resolution of the forward guidance puzzle the fiscal multiplier puzzle and the paradox of flexibility as the monetary friction becomes vanishingly small the models converge to the basic nk model and serve to select a particular equilibrium of that model which also offers a resolution of the paradox of toil

monetary news shocks we pursue an empirical strategy to identify a monetary news shock in the u s economy we use a monetary policy residual along with other variables in a vector autoregression var and identify a monetary news shock as the linear combination of reduced form innovations that is orthogonal to the current residual and that maximizes the sum of contributions to its forecast error variance over a finite horizon real gdp declines in a persistent manner after a positive monetary news shock this contraction in economic activity is accompanied by a fall in inflation and a rapid increase in the nominal interest rate

understanding the role of trade ins in durable goods markets theory and evidence the act of trading in a used car as partial payment for a new car resonates with practically all consumers such transactions are prevalent in many other durable goods markets ranging from golf clubs to ct scanners what roles do trade ins play in these markets what motivates the seller to set up a channel to facilitate trade ins intuitively accepting a trade in would appear to stimulate demand for the producer s product but facilitating the resale of these used goods that substitute for new goods might also increase cannibalization although such transactions involve billions of dollars we know relatively little about this practice from the extant research literature this paper develops an analytical model that incorporates key features of real world durable goods markets i coexistence of new and used goods markets ii consumer heterogeneity with respect to quality sensitivity iii firms that anticipate the cannibalization problem arising from the coexistence of new and used goods and iv lemon problems in resale markets whereby sellers of used goods are better informed than buyers about the quality of their particular item in our analysis a trade in policy amounts to an intervention by the firm in the used goods market which reduces inefficiencies arising from the lemon problem it motivates owners to purchase new goods and reduces their proclivity to hold on to purchased goods because of the low price the latter would fetch in a lemon market we also show that trade in programs are more valuable for less reliable products as well as for products that deteriorate more slowly our analysis shows that producers in durable goods markets should consider trade in programs as a matter of routine despite cannibalization concerns arising from a more active resale market a producer s profits will inevitably rise from introducing trade ins given pervasive lemon problems we test the key predictions of the model about price and volume of trade by assembling a data set of transactions of u s automobile consumers and find broad support for our model

industry dynamics and the minimum wage a putty clay approach we document two new findings about the industry level response to minimum wage hikes first restaurant exit and entry both rise following a hike second there is no change in employment among continuing restaurants we develop a model of industry dynamics based on putty clay technology that is consistent with these findings in the model continuing restaurants cannot change employment and thus industry level adjustment occurs gradually through exit of labor intensive restaurants and entry of capital intensive restaurants interestingly the putty clay model matches the small estimated short run disemployment effect of the minimum wage found in other studies but produces a larger long run disemployment effect

evaluating central banks tool kit past present and future abstract we develop a structural dsge model to systematically study the principal tools of unconventional monetary policy quantitative easing qe forward guidance and negative interest rate policy nirp as well as the interactions between them to generate the same output response the requisite nirp and forward guidance interventions are twice as large as a conventional policy shock which seems implausible in practice in contrast qe via an endogenous feedback rule can alleviate the constraints on conventional policy posed by the zero lower bound quantitatively qe1 qe3 can account for two thirds of the observed decline in the shadow federal funds rate in spite of its usefulness qe does not come without cost a large balance sheet has consequences for different normalization plans the efficacy of nirp and the effective lower bound on the policy rate

the reaction of household consumption to predictable changes in social security taxes the key implication of rational expectations and the basic life cycle permanent income hypothesis that predictable changes in income have no effect on the growth rate of consumption expenditures is examined this implication is important for understanding the effectiveness and optimal timing of fiscal policy the causes and propagation of business cycles and the effects of income fluctuations on the growth rate of the economy using household level consumption data from the consumer expenditure survey whether expenditures on nondurable goods increase contemporaneously with predictable changes in social security tax withholding is tested it is found that households do change their consumption expenditures in response to the predictable fluctuations in income induced by the social security tax system

saving and liquidity constraints this paper is concerned with the theory of saving when consumers are not permitted to borrow and with the ability of such a theory to account for some of the stylized facts of saving behavior the models presented in the paper seem to account for important aspects of reality that are not explained by traditional life cycle models copyright 1991 by the econometric society

a further look at the propagation of monetary policy shocks in hank we provide quantitative guidance on whether and to what extent different elements of heterogeneous agent new keynesian hank models amplify or dampen the response of aggregate consumption to a monetary policy shock we emphasize four findings first the introduction of capital adjustment costs does not affect the aggregate response but does change the transmission mechanism so that a larger share of indirect effects originates from equity prices rather than from labor income second incorporating estimated unequal incidence functions for aggregate labor income fluctuations leads to either amplification or dampening depending on the data and estimation methods third distribution rules for monopoly profits that allocate a larger share to liquid assets lead to greater amplification fourth assumptions about the fiscal reaction to a monetary policy shock have a stronger effect on the aggregate consumption response than any of the other three elements

solving the incomplete markets model with aggregate uncertainty using the krusell smith algorithm and non stochastic simulations abstract this article describes the approach to computing the version of the stochastic growth model with idiosyncratic and aggregate risk that relies on collapsing the aggregate state space down to a small number of moments used to forecast future prices one innovation relative to most of the literature is the use of a non stochastic simulation routine

evaluating the impact of investment incentives the case of italy s law 488 1992 abstract italy s law 488 1992 allows firms willing to invest in lagging areas to receive a public subsidy by comparing subsidized firms with firms with rejected applications this paper evaluates whether the program made investments possible that otherwise would not have been made we find evidence that financed firms brought forward investment projects originally planned for the post intervention period to take advantage of the incentives we also find some support that subsidized firms may have taken some of the investment opportunities that unsubsidized firms would have exploited in the absence of incentives

durable goods oligopoly with secondary markets the case of automobiles we study the effects of durability and secondary markets on equilibrium firm behavior in the car market we construct a dynamic oligopoly model of a differentiated product market to incorporate the equilibrium production dynamics that arise from the durability of the goods and their active trade in secondary markets we derive an econometric model and estimate its parameters using data from the automobile industry over a 20 year period our estimates are used to provide a measure of the competitive importance of the secondary market

stimulating housing markets we study temporary fiscal stimulus designed to support distressed housing markets by inducing demand from buyers in the private market using difference in differences and regression kink research designs we find that the first time homebuyer credit increased home sales by 490 000 9 8 median home prices by 2 400 1 1 per standard deviation increase in program exposure and the transition rate into homeownership by 53 the policy response did not reverse immediately instead demand comes from several years in the future induced buyers were three years younger in 2009 than typical first time buyers the program s market stabilizing benefits likely exceeded its direct stimulus effects

household heterogeneity and the transmission of foreign shocks abstract we study the role of heterogeneity in the transmission of foreign shocks we build a heterogeneous agent new keynesian small open model economy hanksome that experiences a current account reversal households portfolio composition and the extent of foreign currency borrowing are key determinants of the magnitude of the contraction in consumption associated with a sudden stop in capital inflows the contraction is more severe when households are leveraged and owe debt in foreign currency in this setting the revaluation of foreign debt causes a larger contraction in aggregate consumption when debt and leverage are concentrated among poorer households closing the output gap via an exchange rate devaluation may therefore be detrimental to household welfare due to the heterogeneous impact of the foreign debt revaluation our hanksome framework can rationalize the observed fear of floating in emerging market economies even in the absence of contractionary devaluations

real balance effects and monetary policy i introduction modern literature on monetary policy rules employs new keynesian optimizing models that do not explicitly include monetary aggregates see e g rotemberg and woodford 1997 clarida et al 1999 taylor 1999 in these models the demand for output derives from the log linearization of the standard euler equation characterizing household s saving decisions the real money stock does not enter the is relation and therefore monetary policy affects output and inflation only through its effect on the real interest rate when the nominal interest rate is the policy instrument it is not necessary to specify a money market equilibrium condition see romer 2000 the practice of neglecting monetary aggregates in monetary policy analysis has recently been questioned by meltzer 1999 mccallum 2001 and nelson 2002 2003 in particular mccallum 2001 points out that although no explicit term involving money appears in the standard new keynesian setup long run inflation can still be pinned down by the economy steady state nominal money growth rate moreover mccallum 2000 2001 andres et al 2001 kremer et al 2003 woodford 2003 ireland 2004a and collard and dellas 2005 analyze the case in which the resources used by consumers in conducting transactions are modeled by a nonseparable function of consumption and real money balances meltzer 1999 2001 argues that changes in real monetary base generate effects on real aggregate demand not summarized by the real interest rate on short term securities nelson 2003 emphasizes the role of money in the transmission mechanism both as a proxy for a whole spectrum of rates of return and as an indicator variable which contains information about the state of the economy the main aim of the present article is to provide additional microfoundations for an explicit role for money in the current macroeconomic debate in particular i derive a real balance effect that explicitly enters the is relation within an optimizing general equilibrium framework of the new keynesian type according to de scitovszky 1941 haberler 1946 pigou 1943 and patinkin 1965 a change in real money balances has an impact on the real financial wealth of consumers and therefore affects consumption and output notably this effect is not considered in traditional models there is in fact empirical evidence showing that real monetary base growth is a significant determinant of consumption and output gap in both the united states and in the united kingdom see chari et al 1995 meltzer 1999 nelson 2002 the present article extends the dynamic stochastic new keynesian setup with money in the utility function by introducing overlapping generations as modeled by yaari 1965 and blanchard 1985 there are good reasons to base the demand side of the economy on a discrete time stochastic monetary version of the yaari blanchard model first this kind of extension allows one to maintain the main characteristics of the so called new neoclassical synthesis that is forward looking behavior of optimizing agents and incomplete nominal adjustment of prices featured in new keynesian theories goodfriend and king 1997 second the derivation of the real balance effect does not require nonseparability in the utility function thus the implications are analytically more tractable 1 third my framework is more general because it includes the immortal representative agent setup as a particular case my analysis attempts to examine whether the presence of an explicit real balance effect in the is relation helps evaluate the role for money in designing monetary policy rules i focus on basic issues concerning the design of monetary policy rules specifically i investigate whether it is necessary for monetary policy to overreact to inflation by raising the nominal interest rate by more than the observed increase in inflation to rule out equilibrium multiplicity

credit crises precautionary savings and the liquidity trap we use a model a la bewly huggett ayagari to explore the eects of a credit crunch on consumer spending households borrow and lend to smooth idiosyncratic income shocks facing an exogenous borrowing constraint we look at the economy response after an unexpected permananent tightening of this constraint the interest rate drops sharply in the short run and then adjusts to a lower steady state level this is due to the fact that after the shock a large fraction of agents is far below their target holdings of precautionary savings and this generates a large temporary positive shock to net lending we then look at the eects on output here two opposing forces are present as households can deleverage in two ways by consuming less and by working more we show that under a reasonable parametrization the eect on consumer spending dominates and precautionary behavior generates a recession if we add nominal rigidities two things happen i supply side responses are muted and ii there is a lower bound on the interest rate adjustment these two elements tend to amplify the recession caused by the credit tightening

the gender pay gap beyond human capital heterogeneity in noncognitive skills and in labor market tastes abstract focused on human capital economists typically explain about half of the gender earnings gap for a national sample of mbas we account for 82 percent of the gap by incorporating noncognitive skills for example confidence and assertiveness and preferences regarding family career and jobs those two sources of gender heterogeneity account for a quarter of the explained pay gap with half due to human capital variables and the other quarter due to hours worked and current job characteristics female mbas appear to pay a penalty for good citizen behavior choosing jobs that contribute to society and characteristics higher ethical standards

economic theory and the world of practice a celebration of the s s model it was the question of how best to balance the costs of ordering and of running out of stock against the costs of holding excess inventory that inspired kenneth arrow theodore harris and jacob marschak to introduce the s s model in 1951 in this celebratory article we show how this model not only answered important practical questions but also opened the door to a quite startling range of important and challenging follow up questions many of great practical importance and analytic depth the s s model has become one of the touchstone models of economics opening new vistas of applied economic theory to all who internalize its structure today it is universally applied to solve questions faced in inventory control the core model elements uncertainty and fixed costs of adjustment are ubiquitous which has resulted in its becoming the general purpose economic model of discrete adjustment the s s model has also become a profound source of inspiration for macroeconomists seeking to understand the role that discrete microeconomic adjustments play in macroeconomic fluctuations looking forward we foresee rapid growth in the use of s s modeling to aid households making complex and costly financial decisions such as when and how to terminate a mortgage in the projected era of household operations research new modeling challenges will arise due to enriched feedback from the world of practice

the environmental effect of green taxation the case of the french bonus malus a feebate on the purchase of new cars the bonus malus was introduced in france in 2008 less polluting cars benefited from a price reduction of up to 1 000 euro whereas the most polluting ones were subject to a taxation of 2 600 euro we estimate the impact of this policy on carbon dioxide emissions in the short and long run if the shift towards the classes benefiting from rebates is considerable we estimate the environmental impact of the policy to be negative while feebates may be efficient tools for reducing co2 emissions they should thus be designed carefully to achieve their primary goal

income and wealth heterogeneity in the macroeconomy how do movements in the distribution of income and wealth affect the macroeconomy we analyze this question using a calibrated version of the stochastic growth model with partially uninsurable idiosyncratic risk and movements in aggregate productivity our main finding is that in the stationary stochastic equilibrium the behavior of the macroeconomic aggregates can be almost perfectly described using only the mean of the wealth distribution this result is robust to substantial changes in both parameter values and model specification our benchmark model whose only difference from the representative agent framework is the existence of uninsurable idiosyncratic risk displays far less cross sectional dispersion and skewness in wealth than u s data however an extension that relies on a small amount of heterogeneity in thrift does succeed in replicating the key features of the wealth data furthermore this extension features aggregate time series that depart significantly from permanent income behavior

an ss model with adverse selection we present a model of the market for a used durable in which agents face fixed costs of adjustment the magnitude of which depends on the degree of adverse selection in the secondary market we find that unlike typical models the ss bands in our model contract as the variance of the shock increases we also analyze a dynamic version of the model in which agents are allowed to make decisions that are conditional on the age of the durable we find that as the durable ages the lemons problem tends to decline in importance and the ss bands contract

durable goods price cycles theory and evidence from the textbook market i introduction one of the features of the market for new textbooks is that the price of new textbooks is relatively inflexible over the life of an edition in the sense that it fails to decline as the end of an edition approaches this inflexibility seems surprising because the availability of used textbooks which are a close substitute for new textbooks rises as the textbook ages furthermore the willingness to pay of a purchaser of a new textbook who plans to resell the book should decline at the end of the edition as the introduction of a new edition will destroy the resale value of the previous edition both of these factors would be expected to put downward pressure on the price of the good as the edition ages our goal of this article is to develop a model of textbook pricing that is capable of explaining this price inflexibility over the life of an edition we model the textbook pricing decision as that of a monopoly seller of a durable good over the life of an edition of the good where the life of the edition is exogenously given at two periods and the introduction of a new edition kills off the used market for the previous edition we assume that the market for the good is made up of two types of consumers high valuation buyers who will keep the good and low valuation buyers who value the option of being able to resell the good in the used market after using the services of the good in the current period the willingness to pay of high valuation buyers will thus be constant over the life of an edition while that of the low valuation buyers will decline in the second period due to the elimination of the used market we show that this model may lead to an optimal price for the durable good that may either rise or fall over the life of an edition and identify two effects that influence the monopolist s pricing decision the first we refer to as the used goods supply effect which is the impact of the quantity of goods available in the used market on the optimal price of new goods in the second period we show that if the quantity of high valuation buyers is sufficiently low the price of new goods may be increasing in the quantity of used goods in the second period this results from the fact that the increased supply of used goods may reduce the elasticity of demand for new goods making it optimal for the monopolist to sell only to high valuation buyers in the second period the second effect is the potential for resale effect which is due to the fact that the ability to sell goods in the used market will raise the willingness to pay of low valuation buyers relative to that of high valuation buyers in the first period the combination of these two effects leads to the possibility that the monopolist will choose to sell to both types of buyers in the first period of the edition but to sell only to high valuation buyers in the second period our empirical analysis tests for the presence of used goods supply and potential for resale effects on the prices of new textbooks we utilize a panel dataset from college bookshops that contains price and quantity information for economics textbooks for each semester between 1997 and 2003 we estimate simple pricing equations with textbook fixed effects instrumental variables are also used to account for the potential endogeneity of a regressor we find that textbook prices increase as the share of used textbooks increases which is consistent with the presence of a used good supply effect in which the increased presence of used goods makes the demand curve for new goods less elastic we also find evidence that prices of the goods are higher in the last period of an edition controlling for the stock of used goods in the market this is consistent with the potential for resale effect our theoretical model can be distinguished from other work that has analyzed the optimal pricing problem for a monopoly seller of a durable good

optimal strategies for trade old for remanufactured programs receptivity durability and subsidy due to its environmental financial and marketing benefits businesses and governments have increasingly embraced remanufacturing however the weak demand for remanufactured reman product severely hinders the implementation of remanufacturing lately trade old for remanufactured tor programs are growing in popularity as they can boost reman product demand in this paper we investigate the conditions when a firm should offer a tor program and how to best implement it our main findings are 1 firms should offer tor programs only when reman product receptivity and new product durability satisfy a certain condition 2 in addition to the reman product receptivity the new product durability also plays a significant role in motivating consumers to participate in tor programs and finally 3 high product remanufacturability and government subsidies are strong incentives for firms to offer their tor programs our analysis provides insights for firms and governments on how to use tor programs to benefit businesses consumers and the environment

time is money rational life cycle inertia and the delegation of investment management abstract many households display inertia in investment management over their life cycles our calibrated dynamic life cycle portfolio choice model can account for such an apparently irrational outcome by incorporating the fact that investors must forgo acquiring job specific skills when they spend time managing their money and their efficiency in financial decision making varies with age resulting inertia patterns mesh well with findings from prior studies and our own empirical results from panel study of income dynamics psid data we also analyze how people optimally choose between actively managing their assets versus delegating the task to financial advisors delegation proves valuable to both the young and the old our calibrated model quantifies welfare gains from including investment time and money costs as well as delegation in a life cycle setting

the spending and debt response to minimum wage hikes abstract immediately following a minimum wage hike household income rises on average by about 250 per quarter and spending by roughly 700 per quarter for households with minimum wage workers most of the spending response is caused by a small number of households who purchase vehicles furthermore we find that the high spending levels are financed through increases in collateralized debt our results are consistent with a model where households can borrow against durables and face costs of adjusting their durables stock jel d12 d14 d91 j38

machine replacement and the business cycle lumps and bumps this paper explores investment fluctuations due to discrete changes in a plant s capital stock the resulting aggregate investment dynamics are surprisingly rich reflecting the interaction between a replacement cycle the cross sectional distribution of the age of the capital stock and an aggregate shock using plant level data lumpy investment is procyclical and more likely for older capital further the predicted path of aggregate investment that neglects vintage effects tracks actual aggregate investment reasonably well however ignoring fluctuations in the cross sectional distribution of investment vintages can yield predictable nontrivial errors in forecasting changes in aggregate investment

microeconomic adjustment hazards and aggregate dynamics the basic premise of this paper is that understanding aggregate dynamics requires considering that agents are heterogeneous and that they do not adjust continuously to the shocks they perceive we provide a general characterization of lumpy behavior at the microeconomic level in terms of an adjustment hazard function which relates the probability that a unit adjusts to the deviation of its state variable from its moving target we characterize rich cross sectionally dependent aggregate dynamics generated by nonconstant hazards we present an example based on u s manufacturing employment and job flows and find that increasinghazard models outperform constant hazard partial adjustment models in describing aggregate employment dynamics

turnover of used durables in a stationary equilibrium are older goods traded more this paper develops a dynamic model with transaction costs to determine the equilibrium resale pattern in a market for a durable good the key result is that the probability of resale is nonmonotonic in the age of the good trade volume is relatively low in the very beginning and in the middle of a good s life this result helps explain observed variations of resale rates across vintages for the u s market of used cars

preferences over wealth experimental evidence abstract preferences over wealth are a channel to explain why households in the aggregate are less responsive when real interest rates fall following such preferences they save more than would be optimal in a standard model however little is known about preferences over wealth empirically we run an intentionally simple lab experiment on intertemporal spending and saving decisions with 180 students under a positive discount factor zero interest and linear utility maximizing behaviour would imply spending any funds instantaneously while half of the participants behave optimally we find a robust pattern where participants on average form and maintain a stock of wealth consistent with wealth entering the utility function directly

solving heterogeneous agent models by projection and perturbation the paper proposes a numerical solution method for general equilibrium models with a continuum of heterogeneous agents that combines elements of projection and of perturbation methods the basic idea is to solve first for the stationary solution of the model without aggregate shocks but with fully specified idiosyncratic shocks afterwards one computes a first order perturbation of the solution in the aggregate shocks this approach allows to include a high dimensional representation of the cross sectional distribution in the state vector the method is applied to a model of household saving with uninsurable income risk and liquidity constraints techniques are discussed to reduce the dimension of the state space such that higher order perturbations are feasible

the new keynesian cross abstract the new keynesian nk cross is a graphical and analytical apparatus for heterogeneous agent hank models expressing key aggregate demand objects mpc and multipliers as functions of heterogeneity parameters it affords analytical insights into monetary fiscal and forward guidance multipliers and replicates the aggregate implications of quantitative hank the key parameter the constrained agents income elasticity to aggregate income depends on fiscal redistribution when it is larger smaller than one the effects of policies and shocks are amplified dampened with uninsurable idiosyncratic uncertainty this translates intertemporally through compounding discounting in the aggregate euler equation into further amplification dampening of future shocks

when do secondary markets harm firms to investigate whether secondary markets aid or harm durable goods manufacturers we build a dynamic model of durable goods oligopoly with transaction costs in the secondary market calibrating model parameters using data from the us automobile industry we find the net effect of opening the secondary market is to decrease new car manufacturers profits by 35 percent counterfactual scenarios in which the size of the used good stock decreases such as when products become less durable when the number of firms decreases or when firms can commit to future production levels increase the profitability of opening the secondary market

balladurette and juppette a discrete analysis of scrapping subsidies this paper studies the effects of subsidies on durable goods markets in particular we focus on a recent policy in france in which the governments of balladur and juppe subsidized the replacement of old cars with new ones to study this policy we construct a dynamic stochastic discrete choice model of car ownership at the household level the resulting decision rules and equilibrium conditions are used to estimate the underlying parameters of the model using aggregate data these policy functions are used to evaluate the short and long run effects of the french policies we find that these policies do stimulate the automobile sector in the short run but through the induced changes in the cross sectional distribution of car ages create the basis for subsequent low activity further while these policies increase government revenues in the short run revenues in the long run are lower relative to a baseline without intervention

unconventional monetary policy and bank risk taking abstract we analyze the presence of bank risk taking associated with unconventional monetary policy in the united states between 2008 and 2015 using corporate syndicated loan data at the bank firm level we measure monetary policy using the identification through heteroskedasticity approach with a var model to identify the risk taking channel we control for time varying heterogeneity in credit demand and supply our results indicate that accommodating monetary conditions are associated with overall lower loan spreads however the spread reduction is lower for riskier firms suggesting that there is no risk taking behavior in the syndicated loan market during the ump period

consumer durables evidence on the optimality of usually doing nothing the authors argue that lumpy nonconvex transaction costs are the norm for a wide range of economic decisions which are thus characterized by inertial behavior application of this idea to the consumption of durable goods yields an s s decision rule which when aggregated highlights the different expected behavior of average expenditure per purchase versus the number of purchases the empirical implications of this rule are presented and compared to other theories a battery of empirical tests generally supports the predictions of the model in particular it does a good job of explaining the time pattern of response of spending on durables to a change in income copyright 1992 by ohio state university press

environmentalism stimulus and inequality reduction through industrial policy did cash for clunkers achieve the trifecta the 2009 american cash for clunkers program which subsidized consumers who scrapped old vehicles and purchased new vehicles was promoted by appealing to multiple constituencies we evaluate the policy and alternatives according to its stated goals emissions reductions economic stimulus and reducing inequality we calibrate a dynamic partial equilibrium portfolio model to match consumer expenditure data from 1998 to 2011 focusing on heterogeneity across cars and trucks we find the program generated 0 17 in environmental benefits 0 28 in consumer surplus and 0 31 in net discounted additional spending per subsidy dollar since subsidies largely went to middle income infra marginal consumers the program exacerbated consumption inequality we evaluate alternative policy designs and find no policy which simultaneously improves all outcomes jel h23 l52 l92 d63

the effects of fiscal stimulus evidence from the 2009 cash for clunkers program we evaluate the impact of the 2009 cash for clunkers program on short and medium run auto purchases our empirical strategy exploits variation across u s cities in ex ante exposure to the program as measured by the number of clunkers in the city as of summer 2008 we find that the program induced the purchase of an additional 370 000 cars in july and august 2009 however we find strong evidence of reversal high clunker counties bought fewer autos in the 10 months after the program expired which offset most of the initial purchases we find no evidence of an effect on employment house prices or household default rates in cities with higher exposure to the program jel codes h20 e62 copyright 2012 oxford university press

the risk free rate in heterogeneous agent incomplete insurance economies abstract why has the average real risk free interest rate been less than one percent the question is motivated by the failure of a class of calibrated representative agent economies to explain the average return to equity and risk free debt i construct an economy where agents experience uninsurable idiosyncratic endowment shocks and smooth consumption by holding a risk free asset i calibrate the economy and characterize equilibria computationally with a borrowing constraint of one year s income the resulting risk free rate is more than one percent below the rate in the comparable representative agent economy

quality standards for used durables an indirect subsidy abstract we construct a theoretical framework to study the impact of quality standards for used durable goods on trade ows pro ts and consumer welfare we show that asymmetric quality standards generate trade in used goods from high to low standard countries while at the same time reducing trade in new goods producers in the exporting country bene t from this change while consumers lose in the importing country consumers are better off but domestic industry is hurt these ndings suggest that quality standards on used goods may be a powerful policy tool whose use should be monitored by the wto

the spirit of capitalism and stock market prices in existing theory wealth is no more valuable than its implied consumption rewards in reality investors acquire wealth not just for its implied consumption but for the resulting social status max m weber 1958 refers to this desire for wealth as the spirit of capitalism the authors examine both analytically and empirically implications of weber s hypothesis for consumption savings and stock prices when investors care about relative social status propensity to consume and risk taking behavior will depend on social standards and stock prices will be volatile the spirit of capitalism seems to be a driving force behind stock market volatility and economic growth copyright 1996 by american economic association

can more public information raise uncertainty the international evidence on forward guidance abstract central banks have used different types of forward guidance this paper reports cross country evidence showing that in general forward guidance mutes the response of government bond yields to macroeconomic news however calendar based guidance with a short horizon counter intuitively raises it using a stylized model where agents learn from market signals it shows that the public release of more precise information about future rates lowers the informativeness of market signals and as a consequence may increase uncertainty and amplify the reaction of expectations to macroeconomic news

the sensitivity of tests of the intertemporal allocation of consumption to near rational alternatives suppose a consumer sets consumption equal to income each period rather than following the optimal permanent income decision rule how much utility does he lose this paper finds that the answer is typically less than 10 cents 1 per quarter in environments specified by popular tests on aggregate data it includes calculations of the costs of excess sensitivity and excess smoothness to income and interest rate changes and the costs of ignoring information it concludes that the theory does not make predictions for aggregate tests that are robust to small costs such as information or transactions copyright 1989 by american economic association

the effect of unemployment on consumption an experimental analysis this paper reports on an experiment that investigates the apparently robust phenomenon of over sensitivity of consumption to current income using a particularly simple formulation we also investigate whether individuals correctly respond to their employment status we find that subjects over react our data enables us to investigate where this over sensitivity originates we conclude that economic agents differ in their ability to plan ahead and understand the dynamic process determining their employment status however agents seem able to respond appropriately to changes in the parameters governing their decision processes in that the comparative static predictions of the theory are largely confirmed

adjustment of consumers durables stocks evidence from automobile purchases this paper tests an optimal s s rule in household durable purchases and examines directly the resulting aggregate expenditure dynamics the observed decision rule responds to income uncertainty and growth as predicted by an s s model resulting from transactions costs tests against liquidity constraints find that about half the households purchase according to an optimal s s rule aggregating the s s rule over households produces a cross section distribution of durables holdings the empirical distribution is similar to that predicted theoretically as is its response to aggregate shocks furthermore simulations of aggregate expenditure based on the household distribution exhibit dynamics consistent with those observed in the 1980s

the timing of purchases and aggregate fluctuations we study the cyclical effects of the timing of durable goods purchases in a general equilibrium model in which both durable and non durable goods are consumed and the durable good is lumpy at the microeconomic level the timing of durable goods purchases supplies some insulation for nondurable consumption over the cycle at the macroeconomic level the timing decisions tend to amplify and propagate wealth and income shocks our model also allows for endogenous price determination when the price of the durable changes due to inflexibility of workers between sectors the effect of adverse shocks is even stronger and longer copyright 2005 wiley blackwell

dynamic product diversity the goal of this paper is to study the frequency of new product introductions in monopoly markets where demand is subject to transitory saturation we focus on those types of goods for which consumers purchase at most one unit of each variety but repeat purchases in the same product category the model considers in nitely lived forward looking consumers and rms we show that the share of potential surplus that a monopolist is able to appropriate increases with the frequency of introduction of new products and the intensity of transitory saturation if the latter is su ciently strong then the rate of introduction of new products is higher than socially desirable excessive dynamic product diversity jel classi cation numbers l12 l13

the role of automatic stabilizers in the u s business cycle most countries have automatic rules in their tax and transfer systems that are partly intended to stabilize economic uctuations this paper measures how eective they are at lowering the volatility of u s economic activity we identify seven potential stabilizers in the data and include four theoretical channels through which they may operate in a business cycle model calibrated to the u s data the model is used to compare the volatility of output in the data with counterfactuals where some or all of the stabilizers are shut down our rst nding is that proportional taxes like sales property and corporate income taxes contribute little to stabilization our second

uncertainty and consumer durables adjustment we characterize infrequent durables stock adjustment by consumers who also derive utility from non durable consumption flows in the presence of idiosyncratic income uncertainty the data we analyse include subjective future income uncertainty measures which we use as instruments in the estimation of relevant parameters of heterogeneous consumers dynamic adjustment problems the data feature two conceptually distinct sources of variation cross sectional heterogeneity of the sampled households dynamic problems and history dependent heterogeneity in their situation during the observation period we note that the latter should affect the likelihood but not the size of stock adjustment decisions and find broad support for theoretical predictions in formal selection controlled regressions based on this insight