Estimating Candidate Valence: Kawai & Sunada (2025)
Distilled · extracted by claude-sonnet-4-6 Jun 26, 2026, verified by claude-sonnet-4-6 Jun 26, 2026, extracted by gpt-6-luna Oct 4, 2026, verified by gpt-6-luna Oct 4, 2026
JEL (IAR-assigned): D72, C57, C51 · assigned from the abstract, not the journal
What this is. This page is a distilled skeleton of Kawai and Sunada (2025). Read the original at https://doi.org/10.3982/ECTA20496 to replicate or extend the results.
The paper develops a structural method for estimating candidate valence (unobservable quality that affects vote share) from data on vote shares, campaign spending, savings, and strategic entry in U.S. House elections from 1984 to 2008. Adapting the control function approach of Olley and Pakes (1996) from production function estimation, the authors embed vote shares in a dynamic election game and use the injectivity of uncontested incumbents’ policy functions to construct a control function for incumbent valence. Challenger valence is identified from the first-order conditions of the candidates’ spending and saving decisions, treating them as a GMM moment system. Results show incumbents have roughly 3.5 percentage-point higher valence than challengers on average, with challengers exhibiting wider dispersion (IQR 9.2 pp vs. 3.8 pp for incumbents). Equalizing challenger and incumbent valence increases the average challenger winning probability from 6.5% to 12.1%. A regression discontinuity decomposition following Lee (2008) finds that the total 10.2 pp incumbency advantage in vote share decomposes into about 21% from valence, 43% from spending, and 19% from policy positions. The valence measure is validated against the observable seriousness dummies of Maestas and Rugeley (2008), showing positive and statistically significant Spearman rank correlations (Table VI, p. 491).
Core results
Section titled “Core results”| # | Result | Locator | Magnitude as reported |
|---|---|---|---|
| R1 | Average valence of incumbents exceeds challengers | Fig. 4, p. 489; text p. 488 | ~3.5 pp vote share advantage; incumbents 0.035 units higher |
| R2 | Dispersion of valence measures | Fig. 4, p. 489; text p. 488 | IQR incumbents 3.8 pp; IQR challengers 9.2 pp |
| R3 | Counterfactual challenger winning probability (equal valence, no spending adj.) | §7, Fig. 8, p. 493 | Rises from 6.5% to 12.1% |
| R4 | Counterfactual challenger winning probability (equal valence, with spending adj.) | §7, Fig. 8, p. 493 | 11.0% vs. baseline 6.5% |
| R5 | Total incumbency advantage (RD estimate) | Table VII col. (i), p. 495 | 10.2 pp (SE 0.012) |
| R6 | Valence component of incumbency advantage | Table VII cols. (ii)-(iii), p. 495; text p. 496 | 2.1 pp combined (~21% of total) |
| R7 | Spending component of incumbency advantage | Table VII cols. (iv)-(v), p. 495; text p. 496 | 4.3 pp (~43% of total) |
| R8 | Policy position component of incumbency advantage | Table VII cols. (vi)-(vii), p. 495; text p. 497 | 1.9 pp (~19% of total) |
| R9 | Open-seat candidates have a lower mean valence than challengers in incumbent races, with a wide distribution | Figure 4, p. 489; text p. 489 | Mean valence is 1.5 pp lower than incumbent-race challengers; IQR 7.8 pp; upper tail resembles incumbents |
| R10 | Winner-loser valence differences vary by candidate type | Figure 5, p. 490; text p. 490 | Mean valence: incumbent winners 0.017 vs losers 0.013; challenger winners 0.052 vs losers -0.023; open-seat winners -0.006 vs losers -0.058 |
| R11 | Party heterogeneity is concentrated among challengers | Figure 5, p. 490; text p. 490 | No significant incumbent-party difference; Republican vs Democratic challenger means are -0.005 vs -0.034 in incumbent races and -0.020 vs -0.044 in open-seat races |
| R12 | Estimated challenger valence correlates positively with observed seriousness measures | Table VI, p. 491; text p. 491 | Spearman rho for Serious 25/50/75/90 = 0.065 [0.008], 0.128 [0.000], 0.128 [0.000], 0.152 [0.000]; qC regression slopes = 0.270 (SE 0.088), 0.705 (0.142), 0.817 (0.169), 0.984 (0.172); N=1,703 each |
| R13 | Model fit closely matches vote-share levels, with some overprediction of incumbent wins | Figure 6, p. 492; text p. 491 | Mean predicted vote share 0.632 vs realized 0.633; predicted incumbent win probability 91.8% vs realized 94.5% |
| R14 | Predicted candidate actions are close to observed spending and savings distributions | Figure 7, p. 492; text pp. 491-492 | Predicted vs actual log spending: incumbents 12.60 vs 12.94, challengers 11.02 vs 11.30; log saving: incumbents 11.42 vs 10.73, challengers 6.64 vs 5.89 |
| R15 | The control-function vote-share estimates imply opposing spending effects for incumbents and challengers | Table IV, p. 486; text pp. 486-487 | Incumbent spending 0.039 (SE 0.020), challenger spending -0.039 (0.011), open-seat spending 0.015 (0.006); one-SD effects about +2.7 pp, -6.9 pp, and +1.5 pp, respectively; first-column SEs use 500 bootstrap samples |
| R16 | OLS reverses the incumbent-spending sign when candidate valence is omitted | Table IV, p. 486; text p. 487 | OLS incumbent-spending coefficient -0.019 (SE 0.004); challenger-spending coefficient -0.027 (0.002) |
| R17 | Spending responses moderate the equalized-valence counterfactual | Figure 9, p. 494; text p. 494 | Log incumbent spending rises about 0.30 (about $144,600); challenger spending rises about 0.18 (about $16,400); incumbent value falls from 3.18 at baseline to 2.97 in either counterfactual |
| R18 | Party-specific RD estimates show distinct valence, spending, policy, and tenure components | Table VII, p. 495; text pp. 495-497 | Democratic/Republican valence estimates 0.026 (SE 0.011)/0.005 (0.009, insignificant); spending 0.526 (0.138)/-0.650 (0.133); policy 0.179 (0.055)/0.169 (0.049); combined tenure 3.989 terms (0.599), or -0.3 pp; N=2,320 in each column |
| R19 | Estimated fund-raising cost and spending-benefit parameters | Table V, p. 488 | c1=0.001 (SE 0.000), c2=0.158 (0.038), etaI=5.972 (0.732), etaC=12.781 (3.945), alpha=2.670 (0.158), gamma=0.021 (0.005); standard errors use 500 bootstrap samples |
| R20 | Estimated average fund-raising costs and personal benefits from spending | Figure 3, p. 488; text pp. 487-488 | Mean cost relative to win utility: contested incumbents 0.238, challengers 0.162, uncontested incumbents 0.155; mean spending benefit: 0.076, 0.070, and 0.074, respectively |
| R21 | Challenger entry and entrant policy positions respond to candidate and district characteristics | Table III, p. 485; text pp. 485-486 | Republican/Democratic entrant mean absolute policy position 0.888 (SE 0.137)/0.630 (0.149); higher Republican partisanship predicts more Democratic-incumbent challenger entry but less Republican-incumbent challenger entry; unemployment raises entry when incumbent and President share a party; tenure predicts more extreme entrants (mean-position coefficient 0.017, SE 0.004) |
| R22 | Policy extremity and election-cycle effects enter vote shares, while tenure is insignificant | Table IV, p. 486; text pp. 486-487 | betaP=-0.031 (SE 0.021), implying a 4.5 pp penalty for the most extreme candidate in a centrist district; beta tenure=-0.001 (0.002, insignificant); same-party presidential midterm coefficient=-0.030 (0.009) |
Overall (paper’s conclusion). Incumbents hold a persistent and quantitatively meaningful valence advantage over challengers that extends beyond spending capacity and more centrist policy positions. The 10.2 pp total incumbency advantage decomposes into roughly 21% from valence, 43% from spending, and 19% from policy positions, implying that spending-focused interventions such as subsidizing challengers’ campaigns will be only partially effective. Open-seat candidates’ valence distribution resembles that of incumbents in its upper tail, but has a larger mass of low-valence candidates.
Theory / model
Section titled “Theory / model”The paper embeds vote shares in a dynamic Markov Perfect Equilibrium model of U.S. House elections (solution concept: Maskin and Tirole (1988)). In each period , a stage game is either an election with an incumbent or an open-seat election. State variables for contested elections are .
Vote share equation. The incumbent’s vote share is (p. 467, eq. 1):
where are spending (disbursements) of the incumbent and challenger; are their policy positions; is the district’s ideal policy position; is the incumbent’s tenure; is a vector of district controls; are the unobservable valence terms (candidate fixed effects in vote share units); and . The winning probability follows (p. 468, eq. 2):
Incumbent’s dynamic program. Facing a challenger with known valence and policy , the incumbent chooses spending and savings to solve (p. 468, eq. 3):
where . Here is the normalized utility from winning, is the fund-raising cost (strictly decreasing in , so higher-valence incumbents face lower marginal cost), is the consumption value of spending, , and is the endogenous retirement probability. The ex ante value function before the challenger’s entry decision realizes is (p. 470, eq. 4):
where is the equilibrium entry probability and is the joint distribution of the entering challenger’s valence and policy.
Challenger’s problem. The general election challenger solves (p. 470, eq. 5):
A potential challenger enters if and only if , where the entry threshold is defined implicitly by (entry cost ; p. 471). Challengers with higher valence are more likely to enter.
Entry and primary-selection objects. The probability that entrant m wins the primary integrates the reduced-form nomination probability over the other entrants (p. 470, eq. 6):
The endogenous probability of any challenger entry follows from the candidate-specific valence cutoffs (p. 472, eq. 7):
For two potential entrants, the selected general-election challenger’s joint valence-policy distribution is decomposed by whether only candidate 1 enters, only candidate 2 enters, or both enter and a primary winner is selected (p. 472, eq. 8):
The first term in (8), the probability candidate 1 enters alone with valence and policy below the cutoffs, is (p. 472, eq. 9):
For N=2, the probability entrant 1 wins the primary integrates the nomination probability over entrant 2’s policy and valence above the entry cutoff, plus the probability entrant 2 does not enter (p. 472, eq. 10):
Two propositions that drive identification. Proposition 1 (Injectivity, p. 473): If the marginal cost of fund-raising is strictly decreasing in , then the policy functions of uncontested incumbents are one-to-one from to , holding other state variables fixed. This mirrors the invertibility of the investment function in Olley and Pakes (1996) and allows expressing as a function of observables. Proposition 2 (Sufficient statistic, p. 473): is a sufficient statistic for the distribution of the general-election challenger’s valence . This parallels the propensity score in Olley and Pakes (1996) and allows conditioning out the challenger selection bias.
Method
Section titled “Method”The four-step estimation adapts the control function strategy of Olley and Pakes (1996) to handle two unobservables ( and ) and a dynamic game structure.
The sufficient statistic for the selected challenger’s valence distribution implies the conditional mean restriction (p. 475, eq. 11):
Step 1: Vote share equation and incumbent valence. By Proposition 1, substitute into the vote share equation. Decompose and use Proposition 2 to write . The endogeneity-corrected vote share equation becomes (p. 476, eq. 1’):
where is orthogonal to by construction, so and are valid instruments. The coefficients and are identified by variation in holding constant. The sieve minimum distance estimator of Ai and Chen (2003) is applied to the semiparametric equation.
Step 2: Challenger valence and structural parameters. The first-order conditions of the contested incumbent’s spending and saving decisions jointly identify challenger valence and structural parameters . The spending and saving FOCs are (p. 478, eqs. 12-13):
where is the standardized expected vote margin (p. 478, eq. 14):
GMM treats the FOCs as moment conditions and identifies by requiring that the two expressions for obtained from eqs. (12) and (13) coincide at the true parameter values.
Estimation sequence and moments. Section 3.3 (p. 480) estimates the entry probability and entrant-policy distribution first, then estimates the conditional vote-share equation by sieve minimum distance. Candidate payoff parameters and challenger valence are estimated by GMM using the spending and saving first-order conditions (eqs. 12-13); continuation values use forward simulation after nonparametric maximum-likelihood estimation of action distributions, policy functions, retirement, and state transitions. Open-seat parameters use analogous GMM conditions, and remaining candidate valences are recovered by stacking the four candidate first-order conditions per contested election as moments (Supplemental Appendix 10.6). The paper fixes the two-year discount factor at 0.9 and normalizes utility from winning to 1 (p. 478).
Forward simulation of continuation values. The continuation value and its derivative are computed by forward simulation using the methods of Hotz, Miller, Sanders, and Smith (1994) and Bajari, Benkard, and Levin (2007), estimating the distribution of actions and outcomes nonparametrically without solving for an equilibrium at each candidate parameter value.
Functional form specifications (p. 484):
where ensures is positive and strictly decreasing in .
Steps 3-4. Open-seat election parameters (including ) are identified by analogous GMM from open-seat candidates’ FOCs. Valence for incumbents who never appear in uncontested elections is recovered by solving all four FOCs jointly as a system of equations in , stacked as GMM moments.
Empirical specifications
Section titled “Empirical specifications”Vote share specification. The full parameterization estimated in Section 5 is (p. 483):
where is estimated as a linear function of the Republican partisanship index ; is log population density (interacted with incumbent party ) to capture differential urban vs. rural electoral strength; captures retrospective voting through unemployment interacted with whether the incumbent is of the same party as the President; and election cycle FE include midterm, first-term President, and their interaction. Identification uses elections in which the incumbent has previously been uncontested, and requires that varies across elections holding fixed (the control for ).
Key parameter estimates from the control function approach (Table IV, p. 486): (SE 0.020), (SE 0.011), (SE 0.021), (SE 0.003). Standard errors for and are from 500 bootstrap samples. A standard deviation increase in incumbent spending raises incumbent vote share by about 2.7 pp; the same for challenger spending decreases it by about 6.9 pp. OLS estimates of are negative and significant (Table IV, col. 2), reflecting omitted-variable bias from the positive correlation between challenger strength and incumbent spending.
Selection and entrant-policy estimation. The auxiliary selection objects use state covariates including the uncontested-incumbent control, war chest, tenure, policy position, district partisanship, and district controls. The entry probability is estimated by Probit, and entrant policy extremity is modeled as a discretized normal whose mean and standard deviation are linear in the listed state variables (Table III, p. 485):
The functions include seven-knot B-spline bases of the uncontested-incumbent control and election-cycle indicators; the entry equation also includes party-specific constants. Table III reports standard errors in parentheses. The estimation uses incumbent-election states, including contested and uncontested elections; Table I reports 3,065 contested and 787 uncontested incumbent elections.
Validation regression. For each Maestas and Rugeley seriousness indicator (25, 50, 75, and 90), the paper estimates a separate linear regression of the observed seriousness measure on challenger valence (Table VI, p. 491):
Each regression uses 1,703 challengers from 1992-2000; Table VI reports standard errors in parentheses and Spearman rank correlations with their p-values in square brackets. The paper does not report fixed effects for these regressions.
Counterfactual analysis (Section 7, p. 493, Figure 8). To assess the role of valence differences, each challenger’s is replaced by the corresponding percentile of the incumbent valence distribution. The baseline mean challenger winning probability is 6.5%. Equalizing valence without allowing spending to adjust raises this to 12.1%. Allowing candidates to adjust spending to their new equilibrium levels (using the estimated policy functions) yields 11.0%. The moderation comes primarily from increased incumbent spending (log spending increases by about 0.30 points, or roughly $144,600).
Incumbency advantage decomposition (Section 8, p. 494-497, Table VII). Following Lee (2008), the incumbency advantage is defined via the regression discontinuity limit (p. 494, eq. 15):
The same RD regression is estimated replacing the outcome (period vote share) with candidate valence, log spending, and policy position in turn. Using the bias-corrected RD estimator of Calonico, Cattaneo, and Titiunik (2014), the total incumbency advantage is 10.2 pp (SE 0.012, Table VII col. i, bandwidth 0.092). The valence component (combined Democratic and Republican RD estimates multiplied by the vote share effect) is 2.1 pp. The spending component (Democratic and Republican log spending RD estimates, Table VII cols. iv-v, converted via and ) is 4.3 pp. The policy component (Democratic and Republican policy position RD estimates, Table VII cols. vi-vii) is 1.9 pp. Sample for the RD: all election pairs in which neither period is uncontested (N = 2,320 per column).
Datasets used
Section titled “Datasets used”| Dataset | Role in paper | Wiki page |
|---|---|---|
| FEC campaign finance data (2011) | Spending, fund-raising, and savings for all U.S. House candidates, 1984-2008 | no page yet |
| CQ Press electoral database | Electoral outcomes and candidate characteristics | no page yet |
| U.S. Census Bureau (2015) | Congressional district demographics (population density) | Census |
| Bureau of Labor Statistics (BLS, 2011) | Local area unemployment statistics (retrospective voting controls) | BLS |
| POLIDATA (2015) | Presidential vote shares by district (source for partisanship index) | no page yet |
| Bonica (2023) DIME database | Incumbent and challenger policy positions (ideology scores from campaign contributions) | no page yet |
Sample scope: 3,065 contested elections with incumbents, 787 uncontested elections, 445 open-seat elections, all from the 1984-2008 U.S. House election cycle (biennial). Dollar values normalized to 1984 dollars and reported in units of $1,000. Dropped observations include elections in Louisiana and Texas 1996 (affected by Supreme Court redistricting rulings), elections involving major scandals, and elections in which candidates’ spending or savings are near zero, or a policy position is missing.
When to read the full paper
Section titled “When to read the full paper”Read Kawai and Sunada (2025) to (i) replicate or extend the structural valence estimation procedure, in particular the forward simulation of continuation values and the GMM system from first-order conditions (Supplemental Appendices 10.5-10.6); (ii) examine the model fit in detail (Figures 6-7, p. 491-492), which compares predicted vs. realized vote shares and predicted vs. actual candidate actions; (iii) study the full incumbency advantage decomposition with binned scatter plots of valence, spending, and policy position at the 50% vote share threshold (Figures 10-13, pp. 495-498); or (iv) see the cross-validation against the Maestas and Rugeley (2008) seriousness measure (Table VI, p. 491). The replication code and non-restricted data are available at https://doi.org/10.5281/zenodo.14172367; restricted data (CQ Press, POLIDATA) are subject to an exemption and were shared separately with the journal.
Attribution and rights
Section titled “Attribution and rights”Kawai, Kei, and Takeaki Sunada. “Estimating Candidate Valence.” Econometrica, Vol. 93, No. 2 (March, 2025), pp. 463-501. DOI: 10.3982/ECTA20496. © 2025 The Econometric Society. All rights reserved; no Creative Commons license; standard copyright. This page is an extract-only distillation: it reproduces a structured summary of the paper’s methods, equations, and findings for research reference under fair-use conventions for scholarly excerpts. LLM-distilled and verified against the source PDF; results have not been independently reproduced.