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| Identifier: | 04LJUBLJANA830 |
|---|---|
| Wikileaks: | View 04LJUBLJANA830 at Wikileaks.org |
| Origin: | Embassy Ljubljana |
| Created: | 2004-09-03 04:00:00 |
| Classification: | UNCLASSIFIED//FOR OFFICIAL USE ONLY |
| Tags: | KPAO PGOV PINR SI |
| Redacted: | This cable was not redacted by Wikileaks. |
This record is a partial extract of the original cable. The full text of the original cable is not available.
UNCLAS LJUBLJANA 000830 SIPDIS SENSITIVE DEPT FOR EUR/PPD, EUR/NCE AND INR E.O. 12958: N/A TAGS: KPAO, PGOV, PINR, SI SUBJECT: BIAS IN SLOVENE OPINION POLLING: MORE ABOUT AFFORDABILITY THAN POLITICS? Sensitive but unclassified -- protect accordingly 1. (SBU) SUMMARY. As in most countries, the results of public opinion polls in Slovenia are widely discussed among media, politicians, pundits and the public. However, few of these "consumers" are aware of the methodologies that are used or the ease with which polling data can be manipulated. Although misrepresentation of polling data exists in virtually every country, the close relationships between polling centers, media outlets, and political parties in Slovenia make it incumbent on the consumer of opinion polls to study their methodologies closely and take all results with a grain of salt. In an analysis of polling methodologies used by different survey research centers in Slovenia, we have determined that professional pollsters are highly knowledgeable and cognizant of potential biases inherent in their polling methods. However, lack of sufficient funding in a small country often means that polls are done on the cheap and that many of the results contain considerable bias. More difficult to determine is whether bias is ignored intentionally and whether political parties can "commission bias" when paying for a poll. END SUMMARY. 2. (U) In late August, Post's Public Diplomacy Officer (who has a PhD in Political Science and a Master's- level certificate in Survey Research Analysis) conducted a series of interviews with researchers at three major polling centers in Slovenia: the Research Center for Public Opinion and Mass Communication at the University of Ljubljana; the DELO STIK polling agency affiliated with the leading Slovenian daily "Delo"; and the NINA MEDIA polling agency affiliated with the daily "Dnevnik." The following observations and comments are based on the interviews mentioned above and an analysis of the methodologies used by these polling centers. --------------------------------------------- -------- Sample Bias vs. Sampling Error: A crucial distinction --------------------------------------------- -------- 3. (U) One of the main problems with public opinion polls in Slovenia and one of the main causes of faulty analysis by the media lies with the fact that polling agencies often do not take adequate care to ensure that various biases are eliminated from their polling methodologies. Every opinion poll contains some bias and reducing bias to a minimum often comes at a great cost. Thus, every polling agency faces a tradeoff between bias and the cost of utilizing expensive procedures to minimize it. Since most polling agencies are businesses looking to make a profit, cost-cutting is prevalent; nevertheless, lower costs often mean less accuracy. 4. (U) Another major problem is that the media, who are the primary consumers and interpreters of opinion polls, often do not adequately understand the distinction between sample bias and sampling error. Opinion polls that have considerable bias but that have minimal error are often presented to the public as if they were quite accurate. Typically, for example, a media outlet will report that an opinion poll has a margin of error of plus or minus 2-5 percent. What they do not say, however, is that in addition to this margin of error (known as "sampling error"), these polls also--in fact invariably--contain sample bias, which can often skew a given poll by as much as 10, 15, or even 25 percent. A recent conversation with the news director of a major Slovenian television station revealed a complete failure to appreciate this crucial distinction. 5. (U) Sampling error is a measure of the likelihood that a perfectly random sample of the population will have the same characteristics as the population as a whole. Sampling error can be measured using a statistical formula. Sample bias, however, cannot be measured. Sample bias occurs when a polling agency consistently fails to obtain perfectly random samples of the population (often for a multitude of different reasons). For example, if a polling agency were to interview people only within a 50-mile radius of their headquarters, they would consistently fail to obtain a perfectly random sample of the population. However, extensive polling within this 50-mile radius could very well reduce the margin of error to plus or minus 2 percent, or even less. 6. (U) Sample bias is almost impossible to eliminate. Seemingly innocuous methodologies like phoning random numbers to conduct surveys can produce remarkably biased results. For example, poorer households tend not to own telephones (or subscribe to fewer lines), so phone interviews consistently bias the sample in favor of wealthier respondents, who in turn often have different voting preferences. On the other hand, if telephone polls are conducted during the day, they may consistently exclude working professionals (since they are less likely to answer their home phone) and thus overstate the views of the elderly, students, and the unemployed. While telephone penetration rates in Slovenia are estimated at 94 percent, and while most of the centers poll from 3:00-9:00 PM, the prevalence of telephone bias still exists and impacts polling results. This is true especially since "busier" members of household are less likely to answer the phone while those who have more free time are likelier to agree to participate in a survey. 7. (SBU) Polling agency directors were of course cognizant of such methodological flaws, but noted that telephone polls were cheaper than fieldwork and indicated that the exorbitant costs of fieldwork often prevented them from doing more methodologically rigorous polling. Polling on the cheap, they argued, was better than no polling at all. While it is true that some media in the U.S. regularly conduct methodologically substandard polls, these polls are usually discounted by polling professionals, who rely on the far more accurate analyses provided by academic institutions, major media outlets, and reputed polling organizations like Gallup, who have the financial means to conduct methodologically rigorous surveys. In Slovenia, the small number of polling centers and the modest funding they receive means that few polls employ a rigorous methodology. -------------------------------------------- Weighted Samples and Representative Regions -------------------------------------------- 8. (U) One standard method for reducing bias involves the "weighting" of survey samples. This involves factoring into the analysis the known differences between the sample and the population as a whole (usually determined from a census). For example, if you randomly telephone ten people and the result is that 3 women and 7 men answer the phone, and yet you know the population is split evenly between men and women, then to weight the sample you would simply multiply the responses of the women by 7/10 and the responses of the men by 3/10. The problem with this method, however, is that while it may be easy to weight responses by gender or area of residence, there are hundreds of other variables that simply cannot be weighted because their underlying values are unknown (e.g. religiosity, previous affiliation with the Communist Party, etc). Most Slovenian research centers weight their samples by gender, education, and region of residence. However, other variables like affluence, church attendance, and previous support for the Communist regime have all been shown to have a significant--and perhaps even greater--impact on political preferences than the variables currently in use. 9. (U) Another method for minimizing bias is to pick a representative region based on prior election results. This is sometimes called the "Peoria method." If a particular region or municipality within a country had election results that perfectly mirrored the national averages, then polling agencies will sometimes conduct methodologically rigorous polls within those regions in order to predict future election results. The problem with this method, however, is that populations shift and what may be a representative region during one election cycle may no longer be representative during a subsequent cycle. This is especially true if a new set of issues is being raised from one election to the next. ----------------------------------------- Slovenia's EP elections: What Went Wrong ----------------------------------------- 10. (SBU) The failure of most Slovenian polling agencies to adequately predict the European Parliamentary elections is mainly due to various different types of sample bias. While it is impossible to authoritatively determine why such bias occurred, one hypothesis that seems likely is that the winner of the EP elections--Nova Slovenija (NSi or New Slovenia)- -has a rather "unrepresentative" electorate. To cite but one example, NSi attracts both less educated voters and highly educated voters. So, if a polling agency samples a population and weights the sample by education, they may actually be missing the two extremes--the uneducated and the highly educated--and hence the result may under-represent the percentage of voters who would vote for NSi. 11. (SBU) Anecdotal evidence from field polls conducted by DELO STIK also indicates that New Slovenia's voters tend to be more fearful of the government (a relic of the Communist system), and hence less likely to answer public opinion polls out of fear that the government may be trying to keep tabs on them. If such suspicions really do exist, they could potentially result in a large understatement of the number of NSi voters within a given region. This sort of bias is also more likely in a telephone poll than in a field survey. 12. (SBU) The inability of Slovenian polling agencies to adequately predict the turnout for the EP elections also reflects a different type of bias, one associated with the way the survey questions are phrased and perceived by respondents. It is conventional wisdom that when asking respondents if they plan to vote in an election, 10-15 percent more respondents will claim they intend to vote than actually do. Such "social desirability bias" (as it is commonly known) stems from their desire to appear as conscientious citizens. A poll conducted by the Center for Public Opinion and Mass Communication indicated that even after the election was over, 12 percent more respondents indicated that they had voted than actually did. While polling center researchers were well aware of this bias and generally predicted the low turnout in the EP elections rather accurately, the media seemed more surprised that so many fewer voters would show up than had claimed they would vote. 13. (SBU) A final reason for the poor polling results in the run-up to the EP elections also has to do with the problem of low voter turnout. Many of the polling center directors we spoke with claimed that NSi voters were underrepresented in the pre-election voting because they are much more disciplined than the electorates of other parties (meaning that they are more likely to show up on election day--rain or shine). Since this is a quality that is difficult if not impossible to measure prior to election day itself, the pre-election polls generally overrepresented the other electorates and underrepresented NSi. -------------------------- The Tail Wagging the Dog? -------------------------- 14. (SBU) The bias inherent within different polling methodologies and its effect on the popularity of political parties is not unknown to polling agencies. Researchers at the Center for Public Opinion and Mass Communication told us that without properly weighting a sample for education, the results consistently favor right-of-center parties. From these and other comments, we believe that the effects of different methodologies are well known to those conducting survey data analysis in Slovenia. 15. (SBU) Gossip and conspiracy theories abound in Slovene political circles. Polling results are not immune. The chatter that we hear from our contacts, particularly among opposition members, is that polling is notoriously unreliable. The result, they say, is that the ruling coalition gets a boost from those who want to go with the winner. According to one source, the ruling LDS party commissions their own "real" polls for internal use that are cannily accurate, predicting the actual July European Parliament election results of one party to within half a percentage point. 16. (SBU) The director of Nina Media also admitted that he was personally friendly with many members of LDS and that they frequently joked with him about the results of his polls. Although he categorically denied that pressure was ever put on him to fudge the results, he admitted that most political parties did maintain regular contact with his polling agency and that they sometimes commissioned their own polls. He also confirmed that most parties are keen to benefit from higher polling results. As he said, "no one wants to look unpopular." -------- Comment -------- 17. (SBU) The level of knowledge and expertise among professional pollsters in Slovenia is very high. However, public opinion polls are extremely easy to manipulate by expert pollsters. Polling agencies that compete for contracts have an incentive to maintain a reputation for accurate polling, but that does not mean that other considerations do not come into play. In Slovenia, polling agencies are generally eager to cut costs and conduct polls on the cheap. Since the more accurate methodologies are usually the most expensive-- requiring field interviews and persistence in tracking down randomly chosen respondents--it is natural for agencies to sacrifice accuracy in order to cut costs. However, it is also true that if one wanted to bias a sample in favor of a particular political constellation- -either left-of-center or right-of-center--it would be very easy to do so. In fact, intentional bias of this sort could easily be attributed simply to the high cost of a more rigorous methodology. 18. (SBU) While election results generally validate the accuracy of a given polling agency, it is not impossible for inflated or deflated pre-election polls to encourage or dissuade potential voters and thus influence the result itself. Generally, therefore, one needs to take all polling results, and claims of manipulation, with a grain of salt and be aware of the fact that it is always easy to explain inaccuracies after an election is over. Parliamentary elections in Slovenia will be held October 3. HAAS NNNN
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