When Parties Matter: 
The Conditional Influence of Party Positions 
on Voter Opinions about European Integration.*

by Leonard Ray

Department of Political Science
240 Stubbs Hall
Louisiana State University
Baton Rouge, LA 70803
lray2@lsu.edu

* Paper prepared for presentation at the annual meeting of the Western Political Science Association, Las Vegas, Nevada, March 15-17 2001.  

The European Union is one of the most ambitious attempts in recent history to peacefully integrate sovereign political entities.  In its early years the process of European integration was relatively insulated from public opinion by the general obscurity of intergovernmental negotiations and the prevailing elite consensus in favor of integration.  With the admission of relatively euroskeptical nations, and the expansion of the scope of EU policymaking, European integration has become more controversial and salient to European public opinion.  At the same time, the increasing frequency of treaty revisions, with their attendant referenda, give public opinion a powerful role in constraining the future development of the EU.  It may not be an overstatement to claim that it has never been so important to understand the determinants of public support for the European Union.  This paper argues that political parties can be vital factors in shaping public opinion.
Political parties play a central role linking citizens of a democratic society with the political institutions of that polity.  Rumors of party "decline" notwithstanding, no other organizations have emerged that can play a comparable role in regard to aggregating and articulating the opinions of citizens.  Parties are also important sources of political information, and can exert a powerful influence on public opinion.
This view of political parties as sources of political information and opinion has fallen out of favor in the political science literature.  Since the appearance of Downs’ treatise, the tendency in political science has been to explain similarities between the positions of parties and the opinions of voters by claiming that the parties change their positions in order to maximize votes.  It has been pointed out that this “bottom up” explanation of the mass-elite connection is generally more popular among American political scientists than among Europeans, who tend to describe the relationship between parties and voters as a “top-down” model of elite leadership (see Holmberg 1997.)  Some Americanists argue that this situation is changing as Americans rediscover political persuasion (see Cobb and Kuklinski 1997.)
Such a “top down” model of opinion leadership is particularly appropriate for the topic of public support for the European Union.  With a few notable exceptions, party positions on the issue of European integration have been remarkably stable.  Prior research both by Steenbergen and Scott (1997) and [reference removed] has demonstrated that the direction of the relationship between party position and electorate opinion runs primarily from the party to the electorate.  This paper addresses the contingent nature of political leadership by analyzing the conditional influence of political parties on public support for European Integration.  The opinions of voters will be modeled as a function of the position taken by the party supported by each voter, and the strength of that influence will be assumed to vary systematically.  
The argument that political actors influence public opinion about European integration is not new.  Many scholars have insisted that such an influence exists, although not all have tested this proposition, and the empirical record on this point is mixed.  The hypothesized political influences have been found by some studies, and rejected by others.  Null results and anomalous findings in this literature have given rise to ad hoc speculation and theorizing about the conditional nature of political effects, but these theories have not been systematically tested.  This paper will evaluate several of the arguments found in the literature on public support for European integration as well as new theories drawn from the psychological literature on persuasion.
Early research often concluded that the influence of political elites on European opinion about integration was minimal.  While Ronald Inglehart identified the charismatic euroskepticism of Charles De Gaulle as a political influence on French support for the European Community (Inglehart 1970), the absence of political effects in Britain, Italy, or Germany led him to conclude that party preference has little influence on attitudes about European integration.  Later work cast even more doubt on the extent of political influence and Inglehart wrote in 1971 that issues of integration "transcend" party cleavages  (1971).  Wilgden and Feld concluded that voter perceptions of party positions are somewhat influential, however, they discounted the overall importance of this influence because of the large pro-integration consensus among European elites. (Wilgden and Feld 1976).  Inglehart and Rabier concluded that partisanship has a substantial influence on opinion only in Denmark (1978.)  
The question of elite effects on opinion was revisited in the 1990's.  After casting doubt on the usefulness of postmaterialism as a predictor of support for integration, Janssen urged that research "be directed at the role political elites play in teaching the public what to think about it." (1991 p.468).  Several scholars did turn their attention to political elites, with a focus on political parties.  Evidence from the 1989 European Elections Study indicates that the opinions of party electorates are generally related to the positions taken by parties, although the strength of this relationship varies considerably across nations.  (Van der Eijk and Franklin 1991).  A seminal piece on the economic determinants of EU support endorsed the search for political influences concluding that  "political campaigns, elite actions, and the international environment can independently move public opinion."(Eichenberg and Dalton 1993; p 530).  
However, work inspired by the ratification of the treaty of Maastricht in the early 1990's reached inconsistent conclusions about political effects.  Franklin, Marsh and McLauren (1994) find evidence that voting behavior in the referenda on the Maastricht treaty is linked to support for incumbent parties.  Siune, Svensson, and Tonsgaard reach the opposite conclusion about the Danish referenda of 1992 and 1993, arguing that party affiliation played little role in forming opinions. (1994)  More recent work analyzing almost all of the available data on referenda about the EU has indicated that supporters of incumbent parties do generally support the EU, but that the magnitude of the incumbency effect varies according to institutional characteristics of the referenda. (Sciarini and Hug 2000.)
Research outside of the context of referenda also has found contradictory results about party influence.  Dutch and Taylor examine the link between support for incumbent governments and support for integration, and find no connection.  Nonetheless, they conclude that "the trend in support for EU integration is a result of elite-driven diffusion." (1997; p. 75)  Gabel (1998) finds significant effects for class partisanship and incumbent support, although the magnitude, and in one case, direction, of these effects change over time.  Another recent work in the field clearly demonstrates the patterns of results and non-results often found.  Investigating the determinants of EU support in seven nations, Anderson finds strong political influences in Denmark and France, weaker effects in Ireland and Portugal, and no effects in Belgium, Germany and the Netherlands.  (Anderson 1998).
One difficulty in the literature on political effects on support for European integration is the wide variety of ways in which political effects have been conceptualized and measured.  Some authors have used general ideological positions of parties as proxies for party positions on integration.  Others have assumed that governing parties are naturally sending pro integration cues to their voters by virtue of their incumbency.  Some scholars have obtained actual measures of party positions from voter's perceptions, a practice which opens the door to rationalization effects.  Objective measures of party positions have been used far less frequently, notably by authors such as Wessels 1996, Steenbergen and Scott 1997, and Van der Eijk and Franklin 1991.  
This paper moves beyond the existing literature in three ways.  First, it identifies the factors that strengthen or attenuate the influence of political actors on public opinion.  I suggest that the mixed pattern of results in the literature is explicable because elite influence, while present, will vary with the national political context and the characteristics of the messages sent by political leaders.  Further, I expect that individual voters vary in their responsiveness to party cues.  Second, it demonstrates the influence of partisan cues at four points in time, demonstrating the independence of the results from events such as European elections and referenda.  The data employed were gathered during the "ordinary time" between high profile European events, as well as during referenda and EP election campaigns.  Understanding patterns of party influence on public attitudes towards European integration lies in structural characteristics of political parties, the nature of the national political contexts, and the characteristics of voters.  These characteristics persist between referenda and EP elections, and they condition the role parties play during these "European" events.  Third, it employs interval level measures of the positions of political parties on the issue of European integration.  These measures provide a more accurate indicator of party position than do the commonly used proxies of ideology or incumbency because of the imperfect relationship between incumbency, ideology, and support for the European Union.  The resulting analysis allows for a more precise evaluation of the conditional effects of party positions on electorate opinion.  
	This paper argues that the influence of political parties on public opinion has been understated by previous research in part because this influence is contingent on several factors.  The hypotheses presented below introduce the five factors which I argue will increase or decrease the influence of party cues on individual opinion.

Hypotheses
Several hypotheses about the conditional nature of elite influence on public opinion can be derived from the literatures on European integration and on political communication.  In the literature on European integration, the absence of consistent political effects is alternately attributed to the low salience of the issue of integration, to internal party divisions, and/or to a pro-integration elite consensus.  These factors are sometimes presented as ad hoc explanations for anomalous findings, or used to justify the omission of political variables.  In no case have they been systematically tested.  The literature on political communication identifies several characteristics of individuals which should lead them to be more or less receptive to the cues sent by political parties.  

The party unity hypothesis:
One of the prime suspects in much recent discussion of the weakness of party-voter linkages on the issue of European integration is internal party dissent.  Internal divisions on European issues are often thought to be endemic in European parties.  Frequently scholars have asserted that such internal splits are a product of the mismatch between the cleavage systems that gave rise to parties, and the new issue of European unification. (Bogdanor 1989, Franklin, Marsh and McLaren 1994, and Van der Eijk and Franklin 1996)  As Van der Eijk and Franklin put it:
“The party systems in European countries arose long before the process of European Unification began… The questions, however, which currently are of central importance in the politics of the European Union cut across the divisions between national parties, with minorities even within nominally pro-European parties being often vociferously opposed to all things European” (1996:370).

Disagreement within parties about the correct position to take on European integration can be expected to weaken the ability of a party to influence the opinions of its electorate.  The presentation of contradictory messages by various party leaders will muddle the cues sent by the party to its supporters.  Cues will be muffled as well if internal party divisions deter a party from public discussion of European issues.  By highlighting an issue on which the party is divided, party leaders risk an embarrassing display of public dissent at best and a debilitating party schism at worst.  This logic informs the first hypothesis:
H1. The influence of party positions on voter opinions will be increase as party unity on this issue increases.

The issue salience hypothesis:  
Several theories of party competition posit that issues vary significantly in their importance across the political parties within a party system.  According to the ‘issue-ownership’ hypothesis developed by Petrocik (1996), parties cannot credibly take positions on all possible political issues.  The premise is that people who associate certain views with specific parties, are more receptive to messages that confirm these existing stereotypes.  For this reason, during the electoral campaign, candidates (or parties) are likely to gain the most by advertising on those issues over which they can claim ‘ownership.’
Similarly ‘directional theory’ presumes that issues represent a choice between two sides of a question and that party competition takes place on the basis of centrifugal forces Rabinowitz and Macdonald (1989), Listhaug et al. (1990), Macdonald et al. (1991, 1998).  Voters evaluate the party signaling the strongest stand in their ideological direction as the party ‘best’ situated on that dimension.  The ‘saliency theory’ of party competition also claims that political parties build their electoral coalitions around those issues where they have the support of a majority of the electorate.  Parties stress these issues, while downplaying or ignoring issues where their opponents hold the majority view. Budge and Farlie (1983).  All three of these theories suggest that the salience of an issue is an important variable, and one that will vary across parties.  The differential importance of issues across parties informs the second hypothesis:
H2. The influence of a party’s position on the issue of European integration will have upon voter’s opinions increases as the importance of the issue of European integration to the party increases.

The elite consensus hypothesis:
The national political context also plays a role in mediating the distinctiveness of party cues.  It has been suggested that parties avoid stressing the issue of integration because it is simply not a useful issue for differentiating among parties (Lange and Davidson Schmidt n.d.).  The argument has generally been used in the context of elections to the European Parliament.  “The lack of inter-party policy differences on European matters makes it difficult for parties to fight [European] elections on European issues”(Eijk and Franklin 1996:369).  Duch and Taylor cite consensus as the culprit behind the absence of incumbency effects (1997 p.78).  Conversely, Martin Slater noted the politicization of European issues in the "new" member states of the 1970's.  He attributed this to the activity of counter elites who broke with the prevailing pro EU consensus (1982).  I expect that the existence of an elite level consensus among political parties will suppress the politicization of the issue of European integration, and thus reduce the effectiveness of party cues.  This forms the third hypothesis:
H3. The effect of party positions will increase as the variation in positions taken by political parties of each nation increases.

There is a large literature on political communication which examines the factors which may influence the persuasiveness of political messages.  Many of these factors are characteristics of the actual message such as the use of emotional language, the complexity and the length of the message, etc.  These factors are not directly applicable to the present analysis because the actual text of the cues sent by parties is not readily available.  However, other factors identified by the political communications literature are relevant.  The most important of these are individual level characteristics of message recipients which lead some individuals to be more receptive to persuasive communication than are others.

The affective credibility hypothesis:
One factor identified in the communications literature is the perceived credibility of the source of the communication.  Communications research often distinguished between two distinct facets of credibility.  The first component of credibility is a cognitive one, which indicates the degree to which recipients of a communication view the source as providing accurate information.  This aspect of credibility is termed “cognitive” by Chebat, Filiatrault, and Perrien (1990) “qualification” credibility by Rogers and Bhowmik, (1970) and “expertise” credibility by Sternthal (1978.)  The second aspect of credibility involves the positive affect recipients have for the source of the communication.  This aspect is termed “affective” credibility (Chebat, Filiatrault, and Perrien (1990), “safety” credibility (Rogers and Bhowmik, 1970) or sometimes “trustworthiness” credibility (Sternthal 1978.)  For the present analysis, there is no available data on the perceived accuracy of the various political parties.  It is thus impossible to determine the “cognitive” credibility of each potential source.  The data do, however, permit an estimation of the affective component of credibility.  This informs the fourth hypothesis:  
H4. The effect of party positions will be an increasing function of the strength of party attachment.

	The political interest hypothesis:
Another individual attribute which I expect will mediate the effect of partisan cues is interest in and attention to political matters.  An awareness of the positions of parties would seem the sine qua non of political persuasion.  There is a tradition in political science going back to Rosneau (1961) of describing the flow of political information as a “two step” process where “opinion leaders” accept new messages before they reach a broader mass public.  More recently, Zaller (1992) has shown that those individuals who pay the most attention to the media will react first to shifts in elite opinion.  Likewise, I would expect the influence of party cues to be greatest for those individuals who are the most interested in politics.
This hypothesis is not uncontroversial.  Some recent research in political communication has demonstrated that interest in political matters may decrease persuadability ( Cobb and Kuklinski 1997.)  The explanation for this effect draws upon the psychological literature on social judgment theory.  As described by Granberg (1982) social judgment theory suggests that stimuli are evaluated “on the basis of the context in which they appear” (307)  The implication for political science is that reactions to new communications are conditioned by previously held attitudes.  While this argument supports the hypothesis about credibility effects presented above, it suggests that individuals who have firmly held opinions about an issue are more likely to react to communications by altering their assessment of the source of the communication than by altering their opinion about the issue.
Results of the psychological research on the mediating effects of involvement are complex.  Petty and Cacioppo have found that involvement increases persuasion effects under some conditions (1979.)  Johnson and Eagly argue that the psychological literature uses “involvement” in three substantially different ways, with corresponding differences in the impact on persuasion (1989, 1990.)  According to their review of the literature, involvement is “value relevant” when the issue in question is part of a subject’s “ego or self concept.”  Value relevant involvement decreases persuadeability because of the subject’s attachment to the attitude in question.  Alternately, involvement can be “outcome relevant” if the issue is of “personal importance” to the subjects.  In this case, involvement increases one’s motivation to process, and thus to accept a persuasive argument.  Finally, “impression involvement” occurs when subjects wish to make a good impression on the source of the persuasive message.  
In this analysis, personal interest in politics is assumed to increase the likelihood that an individual receives and processes cues from political actors.  As such, interest should increase the potential for persuasion by political parties.  This analysis explicitly refuses the inference that increased interest implies persuasion damping “ego involvement” with the issue of European integration.  Therefore the hypothesis to be tested is the following:
H5. The effects of party positions will be strongest for those individuals who are interested in and attentive to political matters.

Data and Measurement
The issue of European integration lends itself to testing the hypotheses presented above.  The existence of the same political issue in multiple national contexts, with comparable cross national data, provides the conditions needed to empirically evaluate the influence of national context on the party-voter relationship, and the multi party political systems of most European nations allow for an examination of party level effects.  The existence of biannual Eurobarometer surveys provides the necessary indicators of individual level characteristics such as political engagement and closeness to parties, as well as a measure of the dependent variable, support for European integration.
These hypotheses about the conditional nature of partisan influences will be tested empirically using public opinion data drawn from the Eurobarometer opinion polls, and party level data collected through an expert survey.  The Eurobarometer data used are drawn from surveys 21, 22, 29, 30, 37, 38, and 44.2 bis which corresponded to the dates of the expert survey data.  The Eurobarometer data were made available through ICPSR, with the exception of corrected data for Eurobarometer 29 which was obtained through the Zentralarchive in Cologne.  The expert survey data on party positions appeared in the European Journal of Political Research (Ray 1998.)  The operationalization of each variable is described briefly below; more detailed information about question wording is presented in Appendix A.

The Dependent Variable: Support for European Integration.
	I measure opinion about European integration using an additive index of responses to two survey questions which have both been asked consistently across the Eurobarometer surveys used in the analysis.  The first question asks respondents to evaluate “efforts being made to unify” Europe, the second asks for an evaluation of “your country’s membership” in the European Union.  (See Appendix A for question and response wording.)    These two questions are workhorses of the European integration literature, and have been used by a number of previous studies (Janssen 1991, Gabel and Palmer 1995, Wessels 1995, Fraser, Nelson and Guth 1997, Gabel 1998.)  While the results of the present analysis are not particularly sensitive to the choice of indicator for the dependent variable, there are certain benefits to the use of the index employed here.  The technique of consolidating these two questions into one index had been shown to produce a particularly reliable indicator of support for European integration (Gabel 1998.)  The use of this measure also permits the comparison of the present results with those of prior research.  The formula for the construction of the index is given in Appendix A.  Summary statistics for this variable are presented in Table 1.

[Insert Table 1 about here]

Independent Variables:
	The analysis in this paper predicts individual opinions about European integration using the positions taken by the political party supported by that individual.  In order to assign party positions to individual respondents, one must first assign respondents to parties.  This is done using responses to the standard Eurobarometer question "If there were a general election tomorrow, which party would you vote for."  There are two benefits of using this contemporary measure of party preference over the alternative retrospective vote question.  First, the retrospective question will not accurately reflect the current party preference of the voter if she has, for any reason, changed party allegiances since the last national election.  Second, the congruence between current and past party preferences will decrease as the time elapsed since the last national election increases.  Because this time since the last election varies considerably across European nations, the retrospective question introduces unnecessary nation specific error into the analysis.
Party positions on the issue of European integration are then mapped onto respondents according to their party preferences.  Data on party positions are drawn from an expert survey conducted in 1996 which provides estimates of the position taken by each party in the European Union in four different time periods, 1984, 1988, 1992, and 1996.  In this survey, described in detail in Ray 1999, country experts were asked to evaluate the positions of each political party in their country on three dimensions.  These dimensions were 1. the overall position of the party on the issue of integration, 2. the extent of internal dissent within the party on the issue of integration, and 3. the importance of the issue to the party.  135 experts responded to the survey, with a mean of 8 respondents per country.  Summary statistics for these variables are reported in Table 2.  The response scales used by the experts are reproduced in Appendix A.  

[Insert Table 2 about here]

Conditional Effects
Five interaction terms are included in the model in order to determine whether the influence of party cues is enhanced by certain national, party and individual level factors.  The national level factor hypothesized to influence the impact of party cues in the extent of “elite consensus” on the issue of integration.  In order to test the elite consensus hypothesis, a measure of the extent of cross party agreement on the issue of European integration is needed.  For this analysis, national variation in party positions is indicated by the standard deviation of party positions in each nation.  The variation in party positions ranges from a low of .93 in Spain in 1988 to a high of 2.85 in Austria in 1996.
Two party level factors are hypothesized to reinforce the ability of parties to influence the opinions of their supporters.  These are party unity and issue importance to the party.  The importance of the issue of integration to the party is measured on a five point scale running from 1 = "issue is of no importance" to 5 = "the most important issue."  As Table 2 indicates, there is a gradual trend of increasing salience of the issue of integration.  The party scoring lowest on this scale is the Dutch Evangelical People’s Party with a 1.33 in 1984 and the highest score is a 4.40 for the Austrian People’s Party in 1998.  Internal party unity is measured on a five point scale running from 1 = majority opposition to the leadership's position, to 5 = complete unity.  No parties fall into the lowest category on this measure.  The lowest observed level of party unity is a 2 for the Swedish Social Democrats in 1996.  Several parties scored a 5 out of 5 for party unity.
The two individual level factors hypothesized to influence the effectiveness of party cues are attentiveness to political matters and strength of attachment to the preferred party.  These are measured using responses to two Eurobarometer survey questions.  Political attention is indicated using frequency of political discussion.  By employing this question, I am assuming that those individuals who discuss politics are more aware of and interested in it than are others.  Of course, as I indicated above, there is the risk that these individuals have strongly held opinions which are not easily shifted by persuasive appeals.  Admittedly, this indicator is a rather blunt instrument.  However, the question does have the unique advantage of inclusion in all of the Eurobarometer surveys analyzed here.  Party attachment was measured using the Eurobarometer question “Do you consider yourself close to any political party?”  Responses ranged from a high of 3 “very close” to a low of 0 “close to no particular party.”

Control variables:
Several other individual level characteristics have been shown to affect opinion about European integration.  Cross-national differences in opinion towards European integration are well documented, and a vector of country dummies is included to capture these effects.  Recent work by Gabel (1998) has identified “human capital” as a particularly strong predictor of individual opinions about the EU.  In fact, Gabel concludes that the substantive effect of human capital factors is much greater than any other set of theoretical measures, including partisanship.  His primary measures of human capital are educational level, occupational status and income.  Measures of these characteristics are thus included as control variables.  Other work has highlighted the existence of a “gender gap” in support for the EU.  (Nelson, Fraser and Guth 1999, Gabel 1998)  Accordingly, a dummy variable for gender is included among the controls.  (See Appendix A for the coding of the control variables.)

Analyses and Results
Four datasets were created by pooling the individual level data from the Spring and Fall Eurobarometers corresponding each year where party position data were available (1984, 1988, 1992, and 1996.)   For each year, the parameters for a regression equation predicting individual support for European integration were estimated using OLS.  In order to model the conditional effect of party cues, five interaction terms are included in the regression equation.  
Each of these interaction terms consists of the indicator for party position on the issue of integration multiplied by one of the factors hypothesized to mediate the influence of party positions.  In order to model the damping effect of elite consensus on party cues, the standard deviation of national party positions was multiplied by the measure of party position to create an interaction term reflecting the additional impact party positions have on individual opinion when parties disagree on an issue.  For the two interactions which capture the influence of party unity and issue importance (to the party), party position is multiplied by a measure for party unity and by the measure of issue importance, both of which are extracted from the expert survey.  The last two interaction terms were included to capture the effects of individual level characteristics which are hypothesized to mediate a respondent’s response to party cues.  These are party position multiplied by political awareness (measured by frequency of discussion) and position multiplied by the indicator of closeness to one’s preferred party.  Each of these five interactions is coded so that the expected sign of the interaction term is positive.
The regression analysis includes parameters for the measure of party position as well as the five variables used to create the interaction terms to ensure that any observed interaction effects are not the spurious effects of the national, party, and individual level factors hypothesized to mediate the influence of party cues.  In addition the demographic and national control variables described above are included.  The full regression equation has 30 parameters and the following form.
Support = α + 1 (Importance  Position) + 2 (Unity  Position) + 3 (Variation  Position) 
+ 4 (Discussion  Position) + 5 (Closeness  Position) + 6 Position + 7 (Importance) 
+ 8 (Unity) + 9 (Variation) + 10 (Discussion) + 11 (Closeness) 
+ 12 Gender + 13 Status + 14 Income + 15 High Education+ 16 Low Education	
+ 17 Denmark + 18 Germany + 19 Greece + 20 Spain+ 21 France + 22 Ireland 
+ 23 Italy + 24 Luxembourg + 25 Netherlands + 26 Britain + 27 Portugal + 28 Sweden + 29 Finland + 30 Austria + Error

The results of the OLS estimation are presented in Table 3.  In all four years analyzed, all five of the interaction terms are positive, as expected.  The results strongly support hypotheses 2, 3, and 5.  The results also support hypothesis 1, with an anomalous result for 1992.  While the results are consistent with Hypothesis 4, they are much weaker suggesting that either the theoretical basis for or operationalization of this hypothesis is problematic.

[Insert Table 3 about here]

The interactions with issue importance, variation in party position, and closeness to preferred party are substantial and statistically significant across all 4 time periods.  Party positions do appear to exert a stronger effect on individual opinions about European integration when the issue is an important to the party, as surmised in Hypothesis 2.  Hypothesis 3, which predicted that party positions would influence opinion more strongly as national level variation in party positions increased, is also strongly supported by these results.  The parameters also support Hypothesis 5, that individuals who feel close to the political party they support will be most affected by the positions taken by that party.  
The results generally support hypothesis 1, that party unity increased persuasion.  The interaction with party unity is significant in three years, but dips well below the level required for statistical significance in 1992.  The decline in the mediating power of party unity in 1992 is suggestive.  1992 coincided with the signature of the treaty of Maastricht and the first round of referenda to ratify that agreement.  Referenda were held that year in two member states where parties were internally divided over European issues (Denmark and France.)  If referenda tend to increase the persuasive power of political parties, then this effect could have compensated for the reduced internal cohesion of the French and Danish parties.
Hypothesis 4 is weakly supported by these results.  The parameter for the interaction with political discussion is substantively small, and drops below statistically significance in both 1992 and 1996.  The declining significance of the interaction with political discussion is also interesting.  As was mentioned above, political awareness could be expected to enhance persuadability if it implies simply a greater likelihood of receiving political cues.  Conversely, it would decrease persuasion if awareness is associated with the holding of firm opinions.  As overall awareness about the European Union increased from 1984 to 1996, the degree to which politically aware individuals hold strong opinions on European issues may well have increased.  If so, the mediating influence of political awareness will gradually decrease, and may eventually become negative.
While these results tell us about the contingent nature of political influence, what do they say about the overall substantive impact of party positions?  The interpretation of the parameter for party position is difficult because of the inclusion of five interaction terms.  The baseline effect of party positions represents the influence party positions would have on individual opinions in the hypothetical (and impossible) event that the values on the interaction terms were all zero.  Therefore this parameter is, by itself, rather meaningless.  Because the effect of party cues is a function of contextual variables, it will vary across individuals.  For any individual, the influence of party position on the opinions of that individual is the sum of the baseline parameter for party position, plus the effects of the interaction terms.  The total effect of party position for a given observation is thus calculated by summing those terms from the regression equation which include party position:
Effect = 6 + 1 (Importance) + 2 (Unity) + 3 (Variation) + 4 (Discussion) + 5 (Closeness)

The substantive magnitude of the effect of party position is easier to interpret if one considers the predicted effects for specific hypothetical cases.  By inserting the mean values of the contextual variables (presented in tables 1 and 2) and the parameters (from Table 3) into the equation above, we can compute the effect of party position on the opinions of the “average” respondent for each year.  These estimates of the total effect of party position on a typical respondent are presented in Table 4.  The estimated effect of party position ranges from 1.250 to 5.516.  It increases steadily from 1984 to 1992, then recedes in 1996.  In substantive terms, for such a “typical” respondent, a shift on party position over the range of possible positions (from 1 to 7) would result in an increase in support of 8.75 in 1984, of 26.523 in 1988, of 38.612 in 1992, and of 25.914 in 1996.  After 1984, this mean effect of party positions is somewhat larger that the effects of the socioeconomic control variables.  

[Insert Table 4 about here]

Perhaps more important than the “mean effect” of party positions is the significant variation in the influence of party cues according to values on the mediating factors.  Table 4 also presents the total effect of party position across a range of values on each of the contextual factors (holding the other contextual variables to their mean values.)  A shift of party position of 1 unit could result is an much as a 7 or 8 point shift in opinion towards integration for respondents with high levels of party attachment, or who support parties for which the issue is an important one.  Given that respondents may score highly on more than one of these variables, the maximum observed values for party influence are even higher than Table 4 suggests.  The highest observed values in each year were 8.98 in 1984, 11.33 in 1988, 12.16 in 1992, and 9.91 in 1996.  This suggests that under certain circumstances (party unity, high issue importance, distinctive party positions, and party closeness) the effects of party positions may overwhelm the direct effects of socioeconomic factors.  Conversely, the impact of party positions disappears when these conditions are absent.    

Discussion
This research indicates that the positions taken by political parties on the issue of European integration do matter for public opinion about European integration.  The position taken by a party does act as a cue for supporters of that party.  However, the strength of this effect varies significantly according to characteristics of the party, of the national context, and of the individual party supporter.  These findings have important implications both for the future development of the European Union and for our broader understanding of the nature of the elite- mass linkage.
The results suggest a further increase in the strength of party-electorate links.  Over the past fifteen years, parties have taken clearer and more differentiated stands on European issues, in part due to the emergence of clearly euroskeptical parties.  The increased salience of the issues surrounding European integration, coupled with the increase in party unity, and in the variation in positions taken by parties should tighten the connection between party positions and the opinions of voters.  
Any expectation of a monotonic increase in the influence of parties is, however, belied by the spike in party influence in 1992.  While four time periods are clearly insufficient for a definitive statistical analysis of temporal effects, the results are suggestive.  1992 stands out as a high water mark for party influence.  The great public visibility of European integration in a year which saw the signature of the Treaty on European Union is the obvious explanation for the increase in party effects in 1992.  In addition, the sudden decline in the mediating effect of party unity in 1992 suggests that when the issue of European integration is particularly salient, parties get their messages out regardless of their internal opposition.
The implications of these findings for the course of aggregate public support for European integration are contingent on developments in the party systems of Europe.  The appearance of Euroskeptical parties in European party systems should increase the impact of party cues, increasing support for the EU among the adherents of pro EU parties while simultaneously increasing opposition among their own supporters.  The net effect will depend on the positions taken by parties. The positions taken by political parties will not only affect public opinion on this issue, but also affect how much influence the parties themselves can exercise.  Though the days of elite level bargaining insulated from public opinion by a “permissive consensus” seem to be over, the fate of the European Union lies as much as ever in the hands of the political leadership of Europe.
The findings also illuminate broader questions of the ability of political elites to shape public opinion.  There is no reason to suspect that the issue of European integration is so particular that these results will not generalize to other political issues and contexts.  To the extent that issues differ in their association with specific parties, the ability of parties to shape opinion on those issues will be affected.  A secular increase or decrease in party attachment will be accompanied by a corresponding change in party persuasiveness.  Party unity bolsters the persuasiveness of parties, although this effect may vanish when an issue is particularly salient.  The determination of the generalizability of these findings is, at it often must be, left to future research.

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Table 1.  Summary Statistics on dependent and independent variables drawn from the Eurobarometer Surveys.
Variable	Year	Mean	Minimum	Maximum	Number of Observations a	
Index of Support for 	1984	71.39	0	100	9931	
European Integration	1988	74.25	0	100	12692	
	1992	76.14	0	100	9500	
	1996	67.21	0	100	36134	
						
Frequency of	1984	.99	0	2	9931	
Political Discussion	1988	.92	0	2	12692	
	1992	1.10	0	2	9500	
	1996	1.96	0	2	36134	
						
Closeness to a	1984	1.55	0	3	9931	
Political Party	1988	1.21	0	3	12692	
	1992	1.32	0	3	9500	
	1996	1.18	0	3	36134	
a  Respondents with missing values on any of the variables used in the regression analysis (Table 3) were excluded.

 Table 2.  Summary Statistics on Party and Contextual Variables from the Expert Survey.a
Variable	Year	Mean	Minimum	Maximum	Number of Observations b	
Party Position	1984	5.32	1	7	9931	
	1988	5.60	1	7	12692	
	1992	5.73	1	7	9500	
	1996	5.53	1	7	36134	
						
Importance of Issue	1984	3.04	1.33	4.22	9931	
to Party	1988	3.17	1.50	4.25	12692	
	1992	3.45	1.86	4.33	9500	
	1996	3.52	1.86	4.40	36134	
						
Internal Party Unity	1984	4.11	2.87	5	9931	
	1988	4.72	2.75	5	12692	
	1992	3.95	2.11	5	9500	
	1996	3.86	2	5	36134	
						
Variation in	1984	1.84	1.11	2.50	9931	
Party Positions	1988	1.76	.93	2.43	12692	
	1992	1.84	1.04	2.61	9500	
	1996	1.83	1.12	2.85	36134	

a  These values differ from those presented in the EJPR (Ray 1998) because they were computed from the individual level datasets produced by merging Eurbarometer survey data with party level data from the expert survey on party positions.  The means should be interpreted as mean scores across individual respondents, or as weighted means of the political parties, where each party is weighted by its popular support as indicated by the Eurobarometer’s party preference question.
b Respondents with missing values on any of the variables used in the regression analysis (Table 3) were excluded.

Table 3.  Regressing Public Support for Integration on Party Positions Interacted with Party Characteristics and National Context.
Independent Variables used to Predict Individual Level EU Support	1984	1988	1992	1996	
Interactions with Party Position:					
     With Issue Importance to Party	2.703**	3.328**	2.458**	1.336**	
     With Party Unity  (6 - Party Dissent)	3.639**	1.174**	.429	1.513**	
     With Variation in Party Positions	1.584**	1.917**	3.110**	1.640**	
     With Political Discussion	0.563*	0.478*	0.469	0.868	
     With Closeness to Party	0.488**	1.163**	1.573**	1.034**	
Baseline effects for Interactions					
    Effect of Party Position	-25.926**	-16.874**	-13.198**	-12.744**	
    Issue Importance to Party	-10.006**	-20.118**	-17.975**	-8.406**	
    Party Unity  (6 - Party Dissent)	20.892**	8.923**	3.297	8.836**	
    Variation in Party Positions	-13.966**	8.108	-13.391	-11.982**	
    Political Discussion	-.288	.734	.082	.414	
    Closeness to Party	-1.478	-4.985**	-8.007**	-4.121	
(control variables continued on next table)					
Adjusted R Square	.175	.183	.137	.125	
Number of Observations	9931	12692	9500	36134	
* = p < .05          ** = p < .01

Table 3 (continued).  Regressing Public Support for Integration on Party Positions Interacted with Party Characteristics and National Context.
Control Variables	1984	1988	1992	1996	
Socio-Economic Controls					
    Gender	-.979*	-2.810**	-1.789**	-1.962**	
    High Occupational Status	3.427**	2.188**	.863	4.917**	
    Income	.660**	1.487**	-1.009**	2.187**	
    Low Education	-3.509**	-2.177**	-3.004**	-2.004**	
    High Education	2.083**	3.050**	4.950**	5.406**	
National Controls (Belgium = reference)					
     Denmark	-24.682**	-37.584**	-11.022	-	
     France	2.497*	-7.387	-.415	7.469**	
     Germany		-27.519	-4.421	4.755**	
     Greece	-9.323**	-15.179	-.022	9.739**	
     Ireland	-7.926**	-	8.154	19.468**	
     Italy	4.396**	1.626	8.510*	17.497**	
     Luxembourg	4.516	-14.770	-	12.394**	
     Netherlands	8.567**	-8.753	2.287	11.086**	
     United Kingdom	-21.129**	-9.930*	-3.399	-4.912**	
     Portugal	NA	-5.111	12.891*	11.210**	
     Spain	NA	14.585**	10.785**	6.512**	
     Austria	NA	NA	NA	-4.580**	
     Finland	NA	NA	NA	-4.126**	
     Sweden	NA	NA	NA	-1.239	
Intercept	85.810**	99.918**	132.083**	72.332**	
Adjusted R Square	.175	.183	.137	.127	
Number of Observations	9931	12693	9500	36134	
* = p < .05          ** = p < .01

Table 4.  Influence of Party Position on Individual Opinion for Different Values on the Contextual and Partisan Variables.

Variable	Value	1984	1988	1992	1996	
Mean party effect	NA	1.250	3.786	5.516	3.702	
						
Party Characteristics						
    Unity of Party †	5	4.48934	4.7609	5.97108	5.43069	
	4	0.85034	3.5869	5.54208	3.91769	
	3	-2.7887	2.4129	5.11308	2.40469	
	2	-6.4277	1.2389	4.68408	0.89169	
	1	-10.067	0.0649	4.25508	-0.6213	
						
    Importance of Issue to Party	5	6.54851	9.8767	9.32624	5.68547	
	4	3.84551	6.5487	6.86824	4.34947	
	3	1.14251	3.2207	4.41024	3.01347	
	2	-1.5605	-0.107	1.95224	1.67747	
	1	-4.2635	-3.435	-0.5058	0.34147	
National Context						
    Deviation of Party Positions	max	2.29607	5.0766	7.69334	5.37729	
	mean	1.25063	3.7865	5.51634	3.70285	
	min	0.09431	2.2261	2.81064	2.54009	
						
Individual Characteristics						
    Frequency of Political Discussion	2	1.9009	4.3027	5.93469	3.74104	
	1	1.3379	3.8247	5.46569	2.87304	
	0	0.7749	3.3467	4.99669	2.00504	
						
    Closeness to Parties	3	2.58971	7.0313	9.72411	6.6239	
	2	2.10171	5.8683	8.15111	5.5899	
	1	1.61371	4.7053	6.57811	4.5559	
	0	1.12571	3.5423	5.00511	3.5219	

† These negative values are artifacts since no parties exhibit unity scores this low.

Appendix A.
Sources and coding of variables in the model.

Dependent Variable
The dependent variable is an additive index of the following two Eurobarometer survey questions:

Q1 “In general, are you for or against efforts being made to unify Western Europe?” 
                     3.  For - very much                                        
                     2.  For - to some extent                                   
                     1.  Against - to some extent                               
                     0.  Against - very much                                    

Q2 “Generally speaking, do you think that your country’s membership of the European Community is a good thing?”  
                     2.  Good thing                                             
                     1.  Neither good nor bad                                   
                     0.  Bad thing                                              

The index of support is scaled to range from 0 to 100.  Support = (Q1 + Q2) * 20.

Independent Variables
The measures of party position, issue importance, and internal party dissent are drawn from an expert survey described in Ray (1999).  These variables are coded as follows:

Party Position is indicated by the mean response of experts to the following query:
The overall orientation of the party leadership toward European integration:
	1 = Strongly opposed to European integration
	2 = Opposed to European integration
	3 = Somewhat opposed to European integration
	4 = Neutral, no stance on the issue of European integration
	5 = Somewhat in favor of European integration
	6 = In favor of European integration.
	7 = Strongly in favor of European Integration

Issue Importance is indicated by expert’s responses using the following scale:
The relative importance of this issue in the party's public stance:
	1 = European Integration is of no importance, never mentioned by the party
	2 = European Integration is a minor issue for the party
	3 = European Integration is an important issue for the party
	4 = European Integration is one of the most important issues for the party
	5 = European Integration is the most important issue for the party

and Internal Dissent is measured as follows:
The degree of dissent within the party over the party leadership's position:
	1 = Complete unity
	2 = Minor dissent
	3 = Significant dissent
	4 = Party evenly split on issue
	5 = Leadership position opposed by a majority of party activists

The measure of inter-party disagreement is simply the standard deviation of party positions for each nation in each year.

Individual level measures of closeness to parties and political engagement are drawn from the Eurobarometer surveys.

The measure of Party Closeness is based upon the following Eurobarometer question:
“Do you consider yourself to be close to any political party?  If so, do you feel yourself to be very close to this party, fairly close or merely a sympathiser?”
3.  Very close
2.  Fairly close
1.  Merely a sympathiser
0.  Close to no particular party

Political Engagement is indicated by the Eurobarometer question about discussion of political issues.
“When you get together with your friends, would you say you discuss political matters frequently, occasionally or never?”
3.  Frequently
2.  Occasionally
1.  Never

Control Variables

The control variables are all taken from the Eurobarometer surveys.

Female is a dummy variable for sex coded 1 if the respondent is female, 0 otherwise.
High Occupational Status is a dummy variable coded 1 if the respondent is a professional, executive, or business owner.
Low Education is a dummy variable coded 1 if the respondent left school at the age of 15 or earlier.
High Education is a dummy variable coded 1 if the respondent left school at or after the age of 20.
Income is the respondent’s income quartile, where 1 indicates the lowest quartile, and 4 the highest.  Note that non respondents are recoded as being at the median income level (2.5).
Country dummies are coded 1 for respondents from that EU member state, and 0 otherwise.  

Abstract

	The literature on public support for European integration often suggests that political elites play an important role shaping public attitudes towards the European Union.  However, empirical findings to date reveal an inconsistent pattern of political effects with partisan variables predicting individual opinion in some contexts, but not in others.  Using data from the Eurobarometer series of surveys, this paper tetsts hypotheses to explain national, partisan, and individual level variations in the strength of the party/voter connection.  The results support the hypothesis that disagreement among parties increases the distinctiveness and persuasiveness of party positions.  Party unity and issue salience are also found to increase the persuasiveness of party cues.  Individuals with higher levels of party attachment are also the most influenced by the positions taken by parties.  These results help to explain when and where political parties will exercise the greatest, and the least, influence over public opinion.