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IQ and the R&D Market Value Puzzle
Anne Marie Knott
Olin Business School Washington University in St. Louis
Carl Vieregger Olin Business School
Washington University in St. Louis [email protected]
James C. Yen Olin Business School
Washington University in St. Louis [email protected]
Abstract
The dominant measures of R&D effectiveness in studies of innovation are patent counts and R&D expenditures. Patent counts are problematic because they are neither universal (less than 50% of firms conducting R&D have any patents) nor uniform (10% of patents account for 85% of economic value). R&D expenditures are problematic because they are an input rather than an output. Moreover both measures exhibit anomalies in models of market value. Thus they are unreliable We propose and test a novel measure of R&D effectiveness (IQ) that appears to be universal, uniform and reliable.
August 22, 2011
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1. Introduction
R&D is important both to firms and the economy. R&D expenditures comprise 5.8% of
annual firm expenditures and the associated intangible assets comprise 5.6% of firm market
value.1 Moreover, R&D is believed responsible for 7% of real GDP growth.2 However two
things suggest R&D is failing to deliver on its promise. At the economic level, for the past fifty
years GDP growth has been slowing despite increasing R&D intensity. Similarly at the firm-
level a Booz-Allen study3 shows little link between R&D spending and performance.
One reason government policy and firm strategy are failing to deliver on R&D’s promise
is a dearth of measures of its effectiveness. The two dominant measures in empirical studies
have been R&D spending (an input measure) and patent counts (an intermediate measure, which
is sometimes treated as an input and other times treated as an output).
Although an input measure (R&D expenditures) can’t directly test effectiveness, it can
test whether firm investment behavior is consistent with behavioral models. To date however
empirical tests of the market value of R&D lead to an empirical puzzle. In particular, tests
indicate increases in R&D increase firm market value, which shouldn’t be true in equilibrium.
In contrast, the intermediate measure (patent counts) can be used as a coarse measure of
effectiveness (patent counts/expenditures), but is neither universal, uniform nor reliable: 1) less
than 50% of firms conducting R&D have any patents; 2) there is substantial variance in patents'
economic value, e.g., Scherer and Harhoff (2000) report that 10% of U.S patents account for 81-
85% of the economic value of all US patents; 3) patent counts are a poor predictor of firm market
value (Hall, Jaffe and Trajtenberg 2005).
1 estimates derived from firms in the 25 most R&D intensive industries 2 http://www.nsf.gov/news/news_summ.jsp?cntn_id=110139 (downloaded May 4, 2009) 3 http://www.strategy-business.com/media/file/sb41_05406.pdf
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What firms, policy makers and academics need is a reliable measure of R&D
effectiveness that matches constructs in formal models (so empiricists can test them) and
facilitates derivation of optimal R&D, so firms can both choose investment levels and determine
if that investment generates the desired output. In addition the measure should be universal
such that it can be generated for all firms engaged in R&D, and uniform such that it can be
compared across firms, or within the firm over time.
A good test of whether a measure of R&D effectiveness satisfies the reliability property
is its ability to predict firm investment behavior and firm market value (since all models of R&D
investment assume firms maximize the net present value (NPV) of long run profits--precisely
what market value captures). In addition the measure should pass simple tests of face validity.
We propose that firm-specific output elasticity of R&D (organizational IQ) (Knott 2008)
satisfies the above criteria, and in addition resolves the empirical anomalies associated with other
measures. Like individual IQ, organizational IQ is normally distributed across firms. In
principle, it captures firms’ technical problem solving capability in much the same way that
individual IQ captures individual analytical problem solving capability: those with higher IQ
solve more problems per unit of input (dollars for firms, minutes for individuals) than those with
lower IQ.
We estimate IQ for publicly traded US manufacturing firms engaged in R&D. We then
demonstrate 1) that IQ predicts firm R&D investment behavior and 2) that IQ resolves the
empirical puzzle of non-decreasing market value to R&D: It is not that increasing R&D
increases market value; it is that firms differ in their IQ, and those with higher IQ both have
higher optimal R&D and higher market value. Finally, we show that R&D spending beyond the
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optimum prescribed by IQ is wasted—market value is non-increasing in R&D above the
optimum.
Although the primary value of the measure is the academic implications for reinterpreting
past empirics and guiding future empirics, there are managerial implications as well. First,
increasing R&D will not increase market value; however increasing IQ will (and this appears
possible). Second, whereas firms seem to have a relative sense of their IQ (those with higher IQ
spend more on R&D), they lack an absolute sense—they tend to deviate from the optimum. We
believe this stems from the fact that firms don't know their IQ (in large part because the measure
hasn't been available). Finally, and most importantly, IQ offers a more universal and precise
measure of R&D effectiveness than existing alternatives. Attention to the IQ measure may
therefore improve R&D effectiveness just as Total Quality Management (TQM) improved
product quality (Zbaracki 1998) and hospital report cards reduced hospital mortality (Dranove,
Kessler, McClellan and Satterthwaite 2003).
The article begins by characterizing the empirical puzzle of non-decreasing market value
of R&D. We articulate how the IQ measure potentially resolves the puzzle. We then empirically
test propositions arising from the "IQ hypothesis" across the set of publicly traded US firms
engaged in R&D.
2. The empirical puzzle of market value to R&D
Theories of innovation, particularly within industrial organization economics (IO)
typically assume a) firms in an industry share a common R&D production function, and b)
market structure and firm R&D behavior are endogenously determined by three exogenous
conditions: demand, technological opportunity and appropriability (See for example Levin and
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Reiss 1988). If all firms in an industry share these conditions, then whether we employ game
theoretic logic (where each firm chooses its R&D investment assuming optimal investment by
rivals), or decision theoretic logic (where the firm chooses a research stream to maximize its
market value), investing beyond optimal levels should be penalized. In other words, if firms
have been investing optimally, then increases in R&D should decrease market value (as should
decreases in R&D).4
This is not borne out by empirical studies. In fact the empirical record consistently
demonstrates the opposite—increases in R&D increase firms’ market value. This was true for
Grabowski and Mueller (1978) who tested the impact of R&D on profits in an effort to examine
the potential role of R&D as an industry entry barrier, for Connolly and Hirschey (1984) who
tested the simultaneous effects of profits, R&D, and market concentration, for Pakes (1985) who
examined the impact of R&D on inventive output, for Jaffe (1988) who examined the impact of
technological opportunity and spillovers on R&D productivity, for Cockburn and Griliches
(1988) who examined the impact of patent protection on firm performance, for Chan,
Lakonishok and Sougiannis (2001) who examined whether the stock market fully values
intangible assets, for Hall, Jaffe and Trajtenberg (2005) who examined whether patent citations
improved estimates for the market value of R&D, and for Nicholas (2008) who examined the
stock market’s changing valuation of corporate patentable assets.
3. The IQ hypothesis
We propose the empirical puzzle of non-decreasing returns to R&D arises from the
theoretical and empirical assumption of a common production function across firms in an 4 One possible explanation for the anomaly is that firms systematically underinvest in R&D. This could occur for two reasons—1) they don’t know the optimal level, or 2) they face budget constraints (however such constraints shouldn’t persist if financial markets are efficient)
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industry. Under such an assumption differences in R&D investment are interpreted as responses
to exogenous shocks. We propose instead that firms differ in their R&D production functions.
Although all inputs are likely to exhibit heterogeneity in their output elasticities, we are
particularly interested in the elasticity of R&D. Following prior work (Knott 2008), we refer to
the firm-specific output elasticity of R&D as organizational IQ. This is captured as in Equation
1:
Y = K LR SA (1)
where:
Y = output
K = capital
L = labor
R = R&D
S = spillovers
A = advertising
Organizational IQ is obtained by estimating firms’ R&D production functions using a
random coefficients model. This allows the researcher to recover firm specific error terms and
interpret them as something meaningful. Thus firm differences are not something to be cleaned
out, but rather are something to lean on (Griliches and Mairesse 1998). This approach to
interpreting random coefficients is similar to Henderson and Cockburn’s (1996) interpretation of
firm fixed effects as capturing flexible managerial integration processes.
Because the firm specific error terms are normally distributed by construction, firm IQ
resembles individual IQ. Both capture problem solving capability. For individuals, IQ is
captured as the speed and accuracy of solving problems of increasing difficulty--within any
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given time constraint, individuals with higher IQ solve more problems correctly than those with
lower IQ. For firms, IQ is efficiency solving new problems. For any given level of R&D
spending, high IQ firms will generate more innovations, or for any given innovation, high IQ
firms will invest less developing it.
If, as we propose, firms differ in R&D elasticity, those IQ differences will have two
effects on market value: a direct effect and an indirect effect. The direct effect is that higher
output elasticity corresponds to higher revenues per dollar of R&D and accordingly higher
market value (net present value of revenues minus cost of R&D). The indirect effect is that the
elasticity endogeneously determines investment. In particular, firms with higher IQ have higher
optimal investment, R*:
1 2 4 5 0 ( )IQK L R S A e dK L R AR R
(2)
1
1
1 2 4 5 0
1*
IQ
RIQK L S A e
(3)
A sample combination of direct and indirect effects of IQ is depicted in Figure 1. The
indirect effect is captured in the lower curve showing the relationship between IQ and
investment: As raw IQ increases from 0.10 to 0.16, optimal R&D increases from $12 million to
16 million (left hand scale). The direct effect is captured in the upper curve showing the
relationship between IQ and market value: as IQ increases from 0.10 to 0.16, and R&D
increases accordingly, then market value increases from 1.3 to 1.6 (right-hand scale). The figure
presents an alternative logic to the empirical puzzle of non-decreasing returns to R&D: It is not
that increasing R&D increases market value, but rather, IQ jointly increases optimal R&D and
market value per dollar of R&D.
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-----------------------------------
Insert Figure 1 about here
-----------------------------------
To test the IQ hypothesis, we estimate three models of market value: simple OLS, fixed
effects (FE), and simulated fixed effects (SFE) (which treats deviations from the firm’s optimal
R&D, R*). Expectations for the market value of R&D differ across the models. Under an
generalized least squares (GLS) model, market value should increase with R&D because greater
R&D reflects higher IQ and accordingly higher output and market value per dollar of R&D.
Under an FE model, the effects of R&D are indeterminate because there is an optimal
level of R&D spending. If on average firms invest at the optimal level, deviations above the
optimum should have negative coefficients, whereas deviations below the optimum should have
positive coefficients. Since a standard FE model will treat excess investment as the inverse of
underinvestment, the net effect will depend on the extent of positive deviations relative to
negative deviations.
Resolving the indeterminacy requires a model that treats deviations above and below R*
symmetrically. Accordingly we construct a "simulated fixed effects" estimation which models
market value as a function of deviations from the firm's optimal R&D investment, R*. Under the
IQ hypothesis, market value should be non-increasing with deviations from R* (both
overinvestment and underinvestment).
4. Empirical approach.
Our empirical test of the IQ hypothesis has two components. The first component tests
whether the IQ measure predicts firm behavior. The second component tests the hypothesized
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relationships between market value and R&D across the three models. Before conducting either
test, we first estimate firms' IQs.
4.1 Estimating Firm IQ5
We derive firm R&D elasticities (IQ) by estimating the firm’s final goods production
function with a random coefficients model that allows for heterogeneity in the output elasticity
for R&D (as well as all other inputs). A random coefficients model represents a general
functional form model which treats coefficients as being non-fixed (across members of a cross-
section or over time) and potentially correlated with the error term. Random coefficient models
are those in which each coefficient has two components: 1) the direct effect of the explanatory
variable and 2) the random component that proxies for the effects of omitted variables. Our use
of a random coefficients specification follows from the need to capture firm specific estimates
for R&D elasticity. Equation 4 models output (value-added, Y) for firm i in year t with random
coefficients for all inputs (capital, K, labor, L, R&D, R, spillovers, S, and advertising, A) as well
as the intercept:
0 0 1 1 2 2 3 3
4 4 5 5
ln ( ) ( ) ln ( ) ln ( ) ln
( ) ln ( ) lnit i i it i it i it
i it i it it
Y K L R
S A
(4)
We estimate Equation 3 using the Stata program, xtmixed. xtmixed fits linear mixed
models (both fixed effects and random effects) using maximum likelihood estimation. The
5 This discussion closely follows Knott 2008 which estimates the R&D production function using revenues as the output variable together with the conventional four inputs (capital, labor, R&D and spillovers). Because we use ultimately examine market value, we changed the output variable to value-added and included the other important intangible asset (brand--captured via advertising) to the production function in Stage 1. In addition, we employ a newer Stata program xtmixed, rather than xtrc. xtmixed utilizes maximum likelihood estimation, which is superior to estimation via generalized least squares (the method in xtrc) (Beck and Katz 2007). Given these changes, estimated coefficients differ slightly from those in Knott 2008.
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random effects, _i, are not directly estimated, but we form best linear unbiased predictions
(BLUPs) of them (and standard errors) using xtmixed postestimation.
4.2 Behavioral impact of IQ
The behavioral tests check that firm R&D behavior corresponds with firm IQ. In
particular, if firms differ in their IQ and if their investment behavior conforms to equation 2, then
R&D should increase with IQ. Note this test assumes firms have an intuitive feel for their
productivity of R&D investments—that firms get them right on average.
4.3 Market value of R&D
The traditional functional form for estimating the market value of R&D was established
by Griliches (1981), and is largely retained in more recent tests (Hall et al. 2005, Nicholas 2008):
'
ln ln 1'it i t it
RQ m d u
A
(5)
This equation is derived from a simple definitional model of market value:
' 'V q A R (6)
where:
Q = V/A' (equivalent to Tobin's Q)
V = firm market value (equity plus debt)
A' = value of conventional assets (plant, equipment, inventories and financial assets)
R' = value of firm's intangible 'stock of knowledge'
q = market valuation coefficient of firm's assets, defined as exp(mi+dt+uit)
This model imposes some restrictive assumptions:
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1) assets exhibit constant returns to scale (CRS)
2) assets are additive in levels
3) the market value coefficient, q, is common across asset classes6
Given concerns with these restrictions, we estimate a more general functional form and
test whether the restrictions hold. To build our model we revert to first principles. The market
value, V, of the firm represents the net present value of future profits, where NPV of profits is
defined as revenues, Y, minus costs, c, divided by the firm’s discount rate, d, minus its growth, g:
( )Y c
V NPVd g
(7)
Substituting for revenues using the firm's production function and specifying costs yields:
1 2 3 4 5 0 /V K L R S A e c d g (8)
We make the assumption that in steady state flows represent the depreciation rates of
asset stocks for both R&D and advertising. This assumption relies on Knott, Bryce, and Posen
(2003) which characterized the knowledge accumulation function in the pharmaceutical industry
and found that R&D stocks reached steady state within three years. Thereafter, spending was
largely that required to compensate for obsolescence and to grow at the industry rate. This
finding of steady-state explains two empirical regularities: econometric equivalence between
stock and flow models and econometric equivalence of models with different lags (Griliches and
Mairesse 1984, Adams and Jaffe 1996). Accordingly, we can approximate stocks using flows7:
1 2 3 4 5 0k l r s a e (9)
We can then estimate market value using equation 10:
6 In some models the coefficient for R&D assets is allowed to be a scalar multiple of q 7 this is true because: Kt=(1-d)(Kt-1) + k Kt= Kt-1-dKt-1 + k in steady state, Kt= Kt-1 therefore k = dKt-1
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0 1 2 3 4 5 6ln ln ln ln ln ln lnV k l r s A d (10)
This approach yields some notable differences from the Griliches specification. First, inputs are
multiplicative (additive in logs). Second, the specification includes advertising. Third, assets are
not constrained to contribute equally to market value. Fourth, there is no CRS assumption.
We estimate equation 10 using three specifications: OLS, FE and SFE. In all cases we
cluster standard errors to account for the possible dependence among observations within firms.
If firms are investing optimally in R&D, then under the IQ hypothesis we expect to find that 3 is
positive and significant in GLS specifications, but non-increasing in simulated FE specifications.
Our primary tests use R&D expenditures as the knowledge asset. However we replicate
tests using patent counts as the knowledge asset. If patents are an output, they should be
significant in GLS and FE regressions of market value. If however they are an input, results
should match expectations for R&D expenditures.
4.4 Data and variables
We estimate firm IQ and the market value of R&D using a twenty-five year panel of all
publicly traded US firms engaged in R&D. Data for the study comes from the Compustat
industrial annual file for all active and inactive firms over the period 1981 through 2006.
Excluded from this data set are firms that are publicly traded subsidiaries of other publicly traded
firms (since their results would have already been reported within their parent firm’s results) as
well as firms trading on non-major stock exchanges (since the data are often pro forma rather
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than realized), firms with headquarters located outside of the US and firms with no advertising
expenditures.8
Firm level data items include (in $MM unless otherwise stated): market value (MVit)9,
value added as revenues minus cost of goods sold (Yit), capital as net property, plant and
equipment (Kit), labor as full-time equivalent employees (1000)(Lit), advertising (Ait), and R&D
(Rit). From these primary data, we derive a secondary measure: firm specific spillovers (Sit)
which is computed as the sum of the differences in knowledge between focal firm i and rival
firm j for all firms in the respective industry with more knowledge than the focal
firm: it jt it jt itj
S R R R R .10
Within the 25-year period, we restricted the sample to firms with at least seven years of
complete data. The final dataset comprises an unbalanced panel of 1177 firms and 13372 firm-
year observations. Summary statistics for these data are presented in Table 1a.
-----------------------------------
Insert Table 1a about here
-----------------------------------
In a secondary dataset we merge Compustat data with patent data collected by the NBER
Patent Data Project (PDP) under the leadership of Bronwyn Hall.11 This dataset includes patent
8 In principle we could include firms who report zero advertising expenditures. However there is a commonly held belief that some zero observations are instances of not reporting. We tested all propositions using an alternative data set that included firms with zero advertising. Whereas results for propositions are robust for this data set, the coefficient estimates for other inputs increase--suggesting an omitted variable problem 9 Market value is calculated as (stock price*common shares outstanding) + book value of preferred stocks + short term and long-term debt. 10 This functional form matches the probability density form in endogenous growth models (Jovanovic and Rob 1989, Jovanovic and MacDonald 1994, and Eeckhout and Jovanovic 2002), which captures the likelihood of obtaining superior knowledge in a random encounter with a rival. Empirical tests show this form to best match empirical reality in US manufacturing firms (Knott, Posen and Wu 2009). We test both 2-digit and 4-digit industry definitions for spillover pools. While results are simlar for both, we use 2-digit pools because they have greater explained variance--suggesting that firms utilize knowledge outside their narrowly defined industry. 11 http://elsa.berkeley.edu/~bhhall/patents.html
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data from 1976 to 2006. To merge the patent data with the Compustat data we follow Besssen
(2008). First, since owners of the patents change over time, patents must be matched to owners
dynamically. These dynamic matches are recorded in DYNAMIC data, and we thus merge
DYNAMIC data with the patent counts data. We then use DYNAMIC data to find the
appropriate gvkey (firm identifier) to assign the patents because patents change ownership when
firms are merged or acquired. Second, we sum over multiple assignees to get patents for each
company and merge this patent data with our Compustat firm data by matching the gvkey’s.
Finally we distinguish the firms that have zero patents from those whose number of patents are
missing. The merged data set (summarized in Table 1b) contains 753 unique firms and 5652
firm-year observations with non-zero patents, thus reducing our total observations by 58%. The
reduction directly illustrates the concern raised in the introduction that patents are not a universal
measure of R&D effectiveness.
-----------------------------------
Insert Table 1b about here
-----------------------------------
5. Results
5.1 Estimating firm IQ
Estimation results for the random coefficients specification of the R&D production
function (equation 3) are presented in Table 2. Our primary interest is in the firm specific
coefficients of R&D, 3i. However we first discuss the production function estimates more
generally. To do so, we compare the random coefficients (RC) estimates (Model 2) to those
from a GLS specification (Model 1).
-----------------------------------
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Insert Table 2 about here
-----------------------------------
Both the RC and GLS models exhibit constant returns to scale for purchased inputs (i.e.,
ignoring spillovers). The sum of purchased inputs is 0.992 in RC:
(0.130+0.478+0.154+0.239=0.992), while it is 1.002 for GLS:
(0.182+0.330+0.232+0.255=1.002). Conventionally we expect non-increasing returns to scale
for own inputs, but increasing returns with the inclusion of spillovers. Thus both specifications
conform to expectations.
Figure 2 presents a histogram of the 3i values for all 1170 firms with sufficient
observations to form estimates. For comparability with individual IQ we have rescaled the
values such that the mean value of 0.230 is set to 100 and the standard deviation of 0.181 is set to
15. Of the 1177 firms, 9.9% have elasticities that differ significantly from the value for 3.12
Thus we reject the conventional view of homogeneous firms.
-----------------------------------
Insert Figure 2 about here
-----------------------------------
To provide intuition for the measure, we present Figure 3 which shows the range of IQs
(min, max and mean) for the twenty industries with the greatest number of firms engaged in
R&D. A few things are worth noting. First, industries vary in their mean IQ. The surgical and
medical instruments and apparatus industry has the lowest mean (91), whereas the electronic
computers industry has the highest mean (108). The second thing worth noting is there is greater
variance of IQ within industries than across industries. On average the IQ range within industry
12 Note that xtmixed generates firm specific standard errors for each 3i. These differ from (and in general exceed) the standard error for 3. Significant IQs are defined using the firm specific standard error.
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is 61.6, though the range is lowest for electronic measurement equipment (26), and highest for
computer programming and data processing (97). This result of greater heterogeneity within
than across industries matches that for other measures of firm performance (Rumelt 1991,
McGahan and Porter 2002)
-----------------------------------
Insert Figure 3 about here
-----------------------------------
5.2 Behavioral impact of IQ
Next we test whether firm R&D investment corresponds with expectations under the IQ
hypothesis. In particular, if firms differ in their IQ and if their investment behavior conforms to
equation 2, then R&D should increase with IQ (lower plot figure 1). Table 3 presents results
from test of a reduced form of equation 213. The results confirm expectations. The coefficient
on IQ is 1.431 and significant at the 0.001 level after controlling for effects of the other inputs.
The economic impact of a standard deviation increase in IQ is to increase R&D spending 93%.
In addition to these formal tests we also present the deviations graphically in Figure 4. In
general firms tend to underinvest. Of the 12354 firm-year observations where we are able to
calculate the optimal R&D (R*), 1569 observations overinvest by more than 50%, while 7738
underinvest by the same amount. Interestingly, the firms most likely to underinvest are those
with an IQ of 110. This suggests perhaps these firms are using a strategy of matching rival R&D
intensity, when their higher IQ calls for higher investment.
-----------------------------------
Insert Table 3 about here 13 We test the equation: ln R = lnIQ + lnK + lnL +lnA
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Insert Figure 4 about here
-----------------------------------
5.3 Market value of R&D
The market value tests estimate R&D elasticity under three empirical specifications of
Equation 10. Table 4 presents results for these tests.
-----------------------------------
Insert Table 4 about here
-----------------------------------
Model 1 presents an GLS specification of equation 10. The coefficient on R&D is
positive and significant. This merely replicates results generating the empirical puzzle. The
empirical puzzle interpretation of the result is that R&D exhibits non-decreasing returns. The IQ
interpretation of the result is that the correlation between R&D and returns is due to an omitted
variable problem—higher IQ firms have both higher optimal R&D and higher market value per
dollar of R&D.
Model 3 presents an FE specification of equation 10. The coefficient on R&D is again
positive and significant. This test provides additional support for the empirical puzzle, but
provides no information on the IQ hypothesis because the impact of R&D on market value is
indeterminate in FE under the hypothesis.
To solve the indeterminacy problem we test a simulated FE specification of equation 10
(Model 5). To do this we decompose R&D spending into two multiplicative components:
optimal R&D, R* and deviation from optimum, R&D/R* (expressed as a ratio to preserve the
functional form of the production function). Results for that test indicate the coefficient on R*
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(.307) is significantly higher than the coefficient on R&D in model 1 (.256). This suggests firms
are better off at the optimum (which of course is by definition). In addition the coefficient on
deviations is significantly different from that on R*. To interpret the results, consider the case of
a firm investing at the optimum. The deviation ratio is 1, so the market value of R&D is (R*).307.
If however firms underinvest by 20%, then the ratio is 0.8, and the contribution from R is
(R*).307* (0.8).240. Thus the market value is 94.8% that at R*. Conversely at spending 20%
above R*, market value is only 4.5% above that at R*.
In sum, results for the behavioral and market value tests are all consistent with the
propositions for the IQ hypothesis. Firms differ in their IQ; firm R&D spending responds to
those differences; and the market value of R&D reflects those differences. Finally, R&D
investment above the optimum has a non-increasing impact on market value.
5.4 Patent tests
The above tests utilize R&D as the knowledge input. Because we are interested in
measures of R&D effectiveness, we also adopt specifications using patent counts as the
knowledge input. Before doing so, we first treat patents as an intermediate output and examine
the impact of R&D on patent counts. The results for this test are presented in Table 5. Table 5
presents the impact of R&D on the expected intermediate output.14 The results indicate that
R&D is highly significant and explains 39% of the variance in patent counts. A 10% increase in
R&D increases patents by 4.7%.
-----------------------------------
Insert Table 5 about here
----------------------------------- 14 We test the equation ln(PatentCounts) = lnR + ε
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Next we replicate the tests of market value replacing the R&D input with patents as the
intermediate input. Again we test GLS and FE specifications of equation 10.15 Results for the
market value of patent counts mimic those for R&D expenditures (both are shown in Table 4).
The coefficient on patent counts is positive and significant in the GLS specification (model 2),
insignificant in the FE (model 4). Thus patents appear to behave like an intermediate input
rather than as an output with intrinsic market value. In particular there appears to be an optimum
level of patents (just as there is an optimal level of R&D). Thus patent counts as a measure of
R&D effectiveness shares all the problems of R&D intensity, but compounds them with
problems of universality and uniformity.
5.5 Robustness checks
In addition to the models presented in Table 4, we performed a number of robustness
checks. With regard to IQ estimation (which flowed through all subsequent analyses) we tested
two different output variables (revenues and value added), and several sample constructions: 10
year versus 25 year, each with and without firms reporting advertising. With regard to functional
form of the market value model, we tested OLS specifications in addition to the GLS
specification, we also tested alternative configurations of the simulated fixed effects model
examining deviations from the optimum. Results for all such checks (available from the
corresponding author) confirm the basic results, but exhibit weaker measures of fit.
5.6 Test of Griliches restrictions
15 We present results for contemporaneous patent counts. However we also tested specifications using patent stocks. Results for patent stocks match those for patent counts: patent stocks are significant in the GLS specification (though less so than patents) and insignificant in the FE specification.
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Finally we tested the three Griliches restrictions. Results indicate the constant returns to
scale restriction is upheld. As noted in the discussion comparing the GLS and the RC
specifications for the production function (Table 2), the sum of purchased input coefficients is
not significantly different from 1.0. The other two restrictions are not upheld. The elasticity of
the assets differs across asset classes (capital, advertising, and R&D) in the market value models
(Table 4). The mean market value of capital is 0.420, whereas that for advertising is 0.145, and
that for R&D is .256. Third, and accordingly, assets are not additive in levels.
5.7 Mutability of IQ.
An obvious follow-on question given the significant impact of IQ on market value is
whether IQ is mutable. If R&D spending only affects market value to the extent it deviates from
the optimum, then a firm wanting to increase its market value through R&D, must first change its
IQ. Is this possible?
To test the mutability of IQ, we reduced the original sample to the set of firms present in
the data for all years between 1987 and 2006, resulting in 478 firms16. We then subdivided that
sample into two ten-year periods (1987-1996 and 1997-2006). We estimated IQ for each firm in
each ten year period according to a modified equation 317. Figure 5a crossplots the estimated
IQs for the late period versus the early period. The diagonal line represents the constant IQ line.
The figure indicates that IQ changes, however, those changes appear to be random.
-----------------------------------
Insert Figure 5 about here
-----------------------------------
16 We have to exclude advertising expenditures from our production model in the following tests because no firm has consecutive advertising data for 20 years. 17 Modified equation 3 becomes ln ( ) ( )ln ( )ln ( )ln ( )ln0 0 1 1 2 2 3 3 4 4Y K L R Sit i i it i it i it i it it
Page 21
Figure 5b summarizes these changes. The table reveals that of the 478 firms in the comparison
subsample, 163 increased their IQ. The mean value of the increase in the raw IQ was 0.114 (of
which 61 changes were statistically significant). The remaining 315 firms decreased their IQ.
The mean value of the decrease was -0.109 (of which 105 changes were statistically significant).
The fact that IQ changes randomly is consistent with the idea that firms don’t fully understand
their IQ nor the factors contributing to it. Again this is not surprising since the measure hasn't
been available.
6. Discussion.
R&D is important both to firms and the economy. Despite its importance, research and
practice are handicapped by the lack of reliable measures for R&D effectiveness. What firms,
policy makers and academics need is a measure of R&D effectiveness that matches constructs in
formal models (so empiricists can test them) and facilitates derivation of optimal R&D, so firms
can both choose investment levels and determine if that investment generates the desired output.
Ideally the measure should also be universal and uniform such that it can be compared across all
firms engaged in R&D.
We proposed that organizational IQ not only satisfied these criteria, but also resolved the
empirical anomalies associated with other measures. We estimated IQ for publicly traded US
manufacturing firms engaged in R&D then tested its implications in models of firm behavior and
market value. Our results indicate that firm behavior and market value conform to expectations
under the IQ hypothesis.
As a byproduct of our main inquiry we also examined the functional form for the market
value of intangible assets. In particular we tested a general form to see whether the restrictions
Page 22
in the more prevalent Griliches form were upheld. We found that while the constant returns to
scale (CRS) assumption was upheld, the common value of assets was not. By extension neither
is additivity of asset classes. Accordingly we advocate use of the more general form in tests of
market value to R&D.
In sum, the academic implications of these findings are 1) a resolution to the empirical
puzzle of market value to seemingly suboptimal behavior, 2) a better understanding of R&D
capability, optimal R&D behavior and the market value of R&D, and 3) perhaps most
importantly a universal, uniform and reliable measure of R&D effectiveness to replace the
proxies of R&D expenditures and patent counts. The IQ measure allows academics to compare
R&D effectiveness across all firms as well as within a firm over time.
There are managerial implications to these results as well. First, increasing R&D will not
increase market value, however increasing IQ will. Moreover, changes in IQ seem feasible.
Future work could examine the firm structures and processes distinguishing high IQ firms from
their lower IQ counterparts to inform what firms need to do to increase their IQ. Again, as with
the academic implications, perhaps the most important managerial implication is the new
measure of R&D effectiveness. Our results suggest firms have a relative sense of their IQ (R&D
spending increases with IQ), however they lack an absolute sense: 1) their R&D investment
tends to deviate from the optimum prescribed by IQ, and 2) IQ seems to change randomly rather
than purposefully. Neither of these results is surprising given the measure hasn’t exist
previously. Our hope is that adoption of the measure will improve R&D effectiveness just as
TQM improved manufacturing quality and hospital report cards improved hospital morbidity.
Page 23
References Adams, J. D., A. B. Jaffe. 1996. Bounding the effects of R&D: An investigation using matched establishment-firm data. RAND Journal of Economics 27 700–721. Beck, N. and J. Katz. 2007. Random coefficient Models for Time-Series-Cross-Section Data: Monte Carlo Experiments, Political Analysis 15: 182-195. Bessen, J. 2008. Matching Patent Data to Compustat Firms, NBER PDP Project User Documentation. Chan, L., J. Lakonishok and T. Sougiannis 2001 The Stock Market Valuation of Research and Development Expenditures. Journal of Finance, 56 (6): 2431-2456. Cockburn, I. and Z. Griliches 1988. Industry Effects and Appropriability Measures in the Stock Market's Valuation of R&D and Patents. American Economic Review, 78 (2): 419-423. Cohen, W., R. Nelson, and J. Walsh. 2000. Protecting Their Intellectual Assets: Appropriability Conditions and Why U.S. Manufacturing Firms Patent (Or Not). NBER Working Paper 7552. Connolly, R. and M. Hirschey 1984. R & D, Market Structure and Profits: A Value-Based Approach. Review of Economics & Statistics, 66 (4): 682-686. Dranove, D., D. Kessler, M. McClellan and M. Satterthwaite, 2003. Is More Information Better? The Effects of Health Care Quality Report Cards, Journal of Political Economy, 111:555-88. Eeckhout, J. & B. Jovanovic. 2002. “Knowledge Spillovers and Inequality.” American Economic Review, 92: 1290-1307. Grabowski, H. and D. Mueller 1978 Industrial research and development, intangible capital stocks, and firm profit rates. Bell Journal of Economics, 9 (2): 328-343. Griliches, Z. and J. Mairesse. 1984. Productivity and R&D at the firm level, in Z. Griliches, ed. R&D, Patents, and Productivity. University of Chicago Press, Chicago, IL. Hall, B., A. Jaffe, and M. Trajtenberg. 2005. Market Value and Patent Citations, RAND Journal of Economics, 36 (1): 16-38. Henderson, R. and I. Cockburn. 1996. Scale, Scope, and Spillovers: The Determinants of Research Productivity in Drug Discovery, RAND Journal of Economics, 27 (1): 32-59. Jaffe, A. 1988. Demand and Supply Influences in R&D Intensity and Productivity Growth. Review of Economics and Statistics, 70: 431-437. Jovanovic, B. & G. MacDonald. 1994. “Competitive Diffusion.” Journal of Political Economy, 102: 24-52.
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Jovanovic, B. & R. Rob. 1989. “The Growth and Diffusion of Knowledge.” Review of Economic Studies, 56: 569-582. Knott, A.M. 2008. R&D/Returns Causality: Absorptive Capacity or Organizational IQ, Management Science, 54: 2054 - 2067. Knott, A.M., D. J. Bryce, and H. E. Posen, 2003. On the Strategic Accumulation of Intangible Assets, Organization Science, 14 (2): 192-207. Knott, A.M., H. E. Posen, and B. Wu. 2009. Spillover Asymmetry and Why It Matters, Management Science, 55: 373 - 388. Levin, R. and P. Reiss. 1988. “Cost-Reducing and Demand-Creating R&D with Spillovers.” RAND Journal of Economics, 19(4): 538-56. McGahan, A. and M. Porter. 2002. What do we know about Variance in Accounting Profitability, Management Science, 48(7): 834-851. Nicholas, T. 2008. Does Innovation Cause Stock Market Runups? Evidence from the Great Crash, American Economic Review, 98 (4): 1370–1396. Pakes, A. 1985. On Patents, R & D, and the Stock Market Rate of Return. Journal of Political Economy, 93 (2):390-409. Rumelt, R. 1991. How Much Does Industry Matter? Strategic Management Journal, 12(3): 167-185. Swamy, P., and G. Tavlas. 1995. Random coefficient models: Theory and applications. Journal of Econometric Surveys, 9(2) 165–196. Zbaracki, M. 1998. The Rhetoric and Reality of Total Quality Management, Administration Science Quarterly, 43: 602-636.
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Table 1a. Summary for full data set
Variable Obs Mean Std. Dev. Min Max
ln(value add) 13372 4.128 2.465 -4.510 11.100ln(capital) 13372 3.178 2.784 -5.809 11.626ln(labor) 13372 0.044 2.284 -6.215 6.776ln(advertising) 13372 1.019 2.755 -6.908 8.821ln(R&D) 13372 1.863 2.490 -6.908 9.408ln(spillovers) 13372 7.319 4.365 -9.210 10.832Firm-level IQ 1177 0.230 0.181 -1.296 1.009
Table 1b. Summary for patent subset
Variable Obs Mean Std. Dev. Min Max
ln(patents) 5652 1.791 1.776 -1.609 8.367ln(patent stock) 5652 4.839 2.100 0.000 10.635ln(value add) 5652 5.498 2.260 -2.323 10.814ln(capital) 5652 4.745 2.536 -2.996 11.340ln(labor) 5652 1.333 2.121 -5.298 6.776ln(advertising) 5652 2.426 2.607 -6.215 8.821ln(R&D) 5652 3.245 2.308 -4.135 9.408ln(spillovers) 5652 7.017 4.796 -9.210 10.774ln(R*) 5652 4.673 2.843 -45.252 11.615Firm-level IQ 753 0.270 0.130 0.001 1.009
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Table 2. Estimates of equation 1
GLS RC
ln(capital) 0.182*** 0.130***(0.007) (0.012)
ln(labor) 0.330*** 0.478***(0.008) (0.016)
ln(advertising) 0.232*** 0.154***(0.004) (0.010)
ln(R&D) 0.255*** 0.230***(0.004) (0.011)
ln(spillovers) 0.003** 0.051***(0.001) (0.004)
Constant 2.800*** 2.545***(0.022) (0.047)
N 13979 13979
Standard errors in parentheses
* p<0.10 ** p<0.05 *** p<0.01
Dependent variable = ln(Value add)
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Table 3. Behavioral test of IQ
GLS
R&D Beta (IQ) 1.431***(0.061)
ln(sales) 0.847***(0.019)
ln(capital) 0.147***(0.014)
ln(labor) -0.262***(0.019)
ln(advertising) 0.074***(0.009)
Constant -3.222***(0.085)
N 13979
Standard errors in parentheses
* p<0.10 ** p<0.05 *** p<0.01
Dependent variable = ln(R&D)
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Table 4. Results of Market Value Tests
1 2 3 4 5
GLSa GLS Patents FEb FE
PatentsGLS with
R*
ln(capital expenditures) 0.420*** 0.593*** 0.249*** 0.285*** 0.410***(0.008) (0.013) (0.013) (0.024) (0.008)
ln(labor) 0.116*** 0.077*** 0.366*** 0.402*** 0.090***(0.009) (0.015) (0.033) (0.057) (0.010)
ln(advertising) 0.145*** 0.191*** 0.104*** 0.142*** 0.127***(0.005) (0.008) (0.015) (0.034) (0.006)
ln(R&D) 0.256*** 0.116***(0.006) (0.021)
ln(patents) 0.023*** 0.015(0.007) (0.013)
ln(R*) 0.307***(0.007)
ln(R&D / R*) 0.240***(0.006)
year effects included included included included included
Constant 3.862*** 4.841*** 4.708*** 4.861*** 3.901***(0.048) (0.129) (0.058) (0.095) (0.050)
N 13372 5915 13372 5915 12354
R2 NA NA 0.585 0.662 NA
Standard errors in parentheses and are adjusted in FE models for clusters in firms
* p<0.10 ** p<0.05 *** p<0.01
a: The R2 is not reported for GLS models
b: The R2 for each FE model is within groups
Dependent variable = ln(Market value)
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Table 5. Impact of R&D on intermediate output
OLS
ln(R&D) 0.465***(0.030)
Constant 0.284***(0.063)
N 5915
R2 0.386
Standard errors in parentheses are adjusted for clusters in firms
* p<0.10 ** p<0.05 *** p<0.01
Dependent variable = ln(patent count)
Page 30
Figure 1. Optimal investment versus R&D productivity (IQ) (Assumes joint contribution from all other inputs=100)
0
10
20
30
40
50
60
70
80
0.020.
030.
040.
050.
060.
070.
080.
090.10.
110.
120.1
30.
140.
150.
160.1
70.
180.
190.20.
210.
220.
230.
240.
25
Op
tim
al R
&D
sp
en
din
g
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
R&
D^I
Q optimal R
Rd IQ
RD for IQ
MV for “IQ”
Real source of MV (IQ)
Page 31
Figure 2. Histogram of firm IQ
050
100
150
200
250
Num
ber
of F
irms
50 100 150Firm IQ
Distribution of Firm IQ
Page 32
Figure 3. Intra-industry versus cross-industry variance in IQ
IQs by Industry
30
50
70
90
110
130
150
2834
2835
2844
3571
3572
3576
3577
3651
3661
3663
3674
3679
3825
3826
3841
3842
3845
7370
7372
7373
Industry SIC
Fir
m-L
evel
IQ
IQ Mean
IQ Max
IQ Min
SIC Mean Max Min Industry2834 105 149 55 Pharmaceutical Preparations2835 96 129 41 In Vitro & In Vivo Diagnostic Substances2844 99 128 76 Perfumes, Cosmetics & Other Toilet Preparations3571 108 127 96 Electronic Computers3572 99 118 65 Computer Storage Devices3576 103 121 81 Computer Communications Equipment3577 97 129 47 Computer Peripheral Equipment, Nec3651 93 108 56 Household Audio & Video Equipment3661 104 142 80 Telephone & Telegraph Apparatus3663 97 120 67 Radio & Tv Broadcasting & Communications Equipment3674 99 125 57 Semiconductors & Related Devices3679 97 120 63 Electronic Components, Nec3825 106 120 94 Instruments For Meas & Testing Of Electricity & Elec Signals3826 103 116 80 Laboratory Analytical Instruments3841 91 114 73 Surgical and Medical Instruments and Apparatus3842 104 128 81 Orthopedic, Prosthetic & Surgical Appliances & Supplies3845 104 147 62 Electromedical & Electrotherapeutic Apparatus7370 106 150 53 Services-Computer Programming, Data Processing, Etc.7372 103 162 68 Services-Prepackaged Software7373 101 142 68 Services-Computer Integrated Systems Design
Page 33
Figure 4. Actual R&D vs R* (Optimal R&D)
020
0040
0060
0080
0010
000
Act
ual R
&D
0 20000 40000 60000 80000Optimal R&D (R*)