Cheap shot from Golding: No political bias in Gleaner-commissioned polls
published: Sunday | May 27, 2007
Byron Buckley, Associate Editor
Bruce Golding, leader of the Jamaica Labour Party (centre), addresses supporters on the campaign trail in Savanna-la-Mar, Westmoreland, earlier this month. He is flanked by party colleagues Dr. Horace Chang (left) and Russell Hammond. Golding has implied that the Gleaner-Bill Johnson polls are biased towards the People's National Party.- photo by Dalton Laing
Stunned by last Sunday Gleaner's poll report that his Jamaica Labour Party (JLP) was trailing the rival People's National Party (PNP) by seven percentage point, Bruce Golding attacked the bearers of the bad news.
According to the JLP leader, Bill Johnson is the PNP's pollster on loan to the Gleaner Company. Cheap shot. The inference to be drawn is that the series of Bill Johnson polls commissioned by The Gleaner are biased in favour of the PNP.
A drowning man grasps at straws. Golding, understandably, might have experienced a sinking feeling on seeing his party drop five points since January when the JLP held a one-point lead over the PNP in Bill Johnson polls done for The Gleaner. Then, there was no PNP labelling of the pollster or The Gleaner.
All honky dory
Everything was, apparently, honky dory with Johnson's poll findings when The Sunday Gleaner's lead story of April 22, screamed, 'Tough to beat - Tufton poised to take St. Elizabeth South West for JLP'. In that story we reported that the JLP, with 52 per cent popular support, was ahead of the PNP at 25 per cent.
The previous week, The Sunday Gleaner reported in a front-page story, 'Portmore seat wide open', that the JLP (29 per cent) was leading the PNP (28 per cent) in St. Catherine South East. Johnson found that the JLP's Arthur Williams (28 per cent) was ahead of the PNP's Colin ************an (24 per cent). There was no complaint from Golding about polling bias.
On May 6, The Sunday Gleaner lead story was headlined, 'PNP ship sinking: JLP says Palmer's resignation indicative of a party in trouble.' The poll findings showed the parties tied at 33 per cent in voter support, but with the JLP's Sally Porteous at 42 per cent leading the PNP's Vando Palmer at 30 per cent. Palmer resigned as candidate two days before the poll results were published.
Furthermore, the May 13 edition of The Sunday Gleaner carried a front-page story, 'JLP has a shot at St. Andrew South East'. We reported the party standings, with the JLP at 35 per cent ahead of the PNP at 30 per cent. Golding must have been pleased; there was no protestation from him.
A tally of the five constituency polls carried by The Gleaner as at last Sunday shows the JLP ahead in three seats and the parties deadlocked in two. A sixth poll result carried today shows the JLP with 29 per cent and the PNP 26 per cent of popular support in St. James West Central. So, where is the PNP bias in The Gleaner's poll reports to which Golding alludes? Could it be that in an effort to steady himself from the impact of the poll findings, he accidentally threw a blow below the belt?
Accuracy of polls
Golding's reaction aside, the publishing of the parties' standings last week - PNP at 34 per cent and JLP at 27 per cent - ignited a firestorm of criticism about the accuracy or validity of Johnson's polls. People have questioned how the national poll findings did not reflect the trend from the constituency polls - a JLP lead. But is this a valid expectation? Can poll findings in five constituencies out of 60 reflect the national political situation?
The answer is no, because these five constituencies are not a representative sample of the entire 60. No attempts should be made to generalise a particular constituency poll finding. There is an exception to this rule which we will address later in this article.
Furthermore, based on the rules of research, the size of the sample (480) used in the constituency polls carries a larger margin of error - five per cent - compared to three per cent for the sample of 822 registered votes used in the national poll. This difference in error margin means the constituency polls are less accurate than the national poll with its smaller error margin. So, any comparison of the constituency poll findings with the national poll results is like comparing apples and breadfruit.
On the matter of margin of error, readers need to interpret poll results bearing this statistic in mind. Let me explain. When the margin of error of three per cent is applied to the PNP's popular standing of 34 per cent as captured by Johnson's recent national poll, the figure could increase or decrease by as much as three per cent in an actual election.
So, conceivably, the poll findings in the constituencies in which Johnson found the JLP leading could shift up or down by the five per cent margin of error in a real election as illustrated in the table.
Of course, movements within the error margin are not uniformed. Factors can affect the PNP and JLP simultaneously, and to different degrees, thus resulting in either party gaining or losing an advantage. In the cases of St. Andrew East, and Manchester Central, where both parties were in deadlock, any movement within the error margin could shift the balance of power.
Part of the difficulty readers expressed in response to the release of the party standings last Sunday was that the national poll results did not reflect the findings at the constituency levels. This is a misunderstanding on the part of some readers.
Pollster's credibility
The national poll results are not the aggregate of 60 mini-polls in constituencies. For the purpose of conducting a national survey, the island becomes one big constituency with respondents drawn from a wide cross-section of areas to ensure the sample is representative. This approach helps to minimise bias from, for example, garrison constituencies or political enclaves.
The credibility of pollster Bill Johnson was also called into question last week. Critics pointed to the variance in his poll findings related to the outcome of the general election in St. Lucia last year.
Close to election day, in an attempt to influence supporters, the ruling party of then Prime Minister Kenny Anthony released poll findings by Johnson indicating that the party was ahead of the opposition party in popular support. But, the ruling party subsequently lost the election six seats to the opposition's 11, while both parties tied for popular support.
Johnson explains that he had conducted a series of polls for the ruling party; and while the first of these showed the ruling party ahead of the opposition in popular support, the latter polls showed the party rapidly losing voter support. In fact, Johnson says, his last poll had accurately predicted a tie in popular votes for each party.
One lesson from the St. Lucian election for us is that the popular vote split does not directly reflect the pattern of voting in constituencies.
As mentioned earlier, there are instances where poll findings in particular constituencies are used to predict generalised outcomes. But, in fact, the prediction is based on historical patterns from actual election outcomes.
For example, St. Elizabeth SW has always gone to the party that forms the government after an election since Independence. Political scientists describe this as a weather-vane seat because it signals the direction of the political winds of change.
Hence, the importance of The Gleaner's probing of the electoral situation in a seat like St. Elizabeth SW. The findings there and in similar-type seats point to the likely national winner of the next general election.
published: Sunday | May 27, 2007
Byron Buckley, Associate Editor
Bruce Golding, leader of the Jamaica Labour Party (centre), addresses supporters on the campaign trail in Savanna-la-Mar, Westmoreland, earlier this month. He is flanked by party colleagues Dr. Horace Chang (left) and Russell Hammond. Golding has implied that the Gleaner-Bill Johnson polls are biased towards the People's National Party.- photo by Dalton Laing
Stunned by last Sunday Gleaner's poll report that his Jamaica Labour Party (JLP) was trailing the rival People's National Party (PNP) by seven percentage point, Bruce Golding attacked the bearers of the bad news.
According to the JLP leader, Bill Johnson is the PNP's pollster on loan to the Gleaner Company. Cheap shot. The inference to be drawn is that the series of Bill Johnson polls commissioned by The Gleaner are biased in favour of the PNP.
A drowning man grasps at straws. Golding, understandably, might have experienced a sinking feeling on seeing his party drop five points since January when the JLP held a one-point lead over the PNP in Bill Johnson polls done for The Gleaner. Then, there was no PNP labelling of the pollster or The Gleaner.
All honky dory
Everything was, apparently, honky dory with Johnson's poll findings when The Sunday Gleaner's lead story of April 22, screamed, 'Tough to beat - Tufton poised to take St. Elizabeth South West for JLP'. In that story we reported that the JLP, with 52 per cent popular support, was ahead of the PNP at 25 per cent.
The previous week, The Sunday Gleaner reported in a front-page story, 'Portmore seat wide open', that the JLP (29 per cent) was leading the PNP (28 per cent) in St. Catherine South East. Johnson found that the JLP's Arthur Williams (28 per cent) was ahead of the PNP's Colin ************an (24 per cent). There was no complaint from Golding about polling bias.
On May 6, The Sunday Gleaner lead story was headlined, 'PNP ship sinking: JLP says Palmer's resignation indicative of a party in trouble.' The poll findings showed the parties tied at 33 per cent in voter support, but with the JLP's Sally Porteous at 42 per cent leading the PNP's Vando Palmer at 30 per cent. Palmer resigned as candidate two days before the poll results were published.
Furthermore, the May 13 edition of The Sunday Gleaner carried a front-page story, 'JLP has a shot at St. Andrew South East'. We reported the party standings, with the JLP at 35 per cent ahead of the PNP at 30 per cent. Golding must have been pleased; there was no protestation from him.
A tally of the five constituency polls carried by The Gleaner as at last Sunday shows the JLP ahead in three seats and the parties deadlocked in two. A sixth poll result carried today shows the JLP with 29 per cent and the PNP 26 per cent of popular support in St. James West Central. So, where is the PNP bias in The Gleaner's poll reports to which Golding alludes? Could it be that in an effort to steady himself from the impact of the poll findings, he accidentally threw a blow below the belt?
Accuracy of polls
Golding's reaction aside, the publishing of the parties' standings last week - PNP at 34 per cent and JLP at 27 per cent - ignited a firestorm of criticism about the accuracy or validity of Johnson's polls. People have questioned how the national poll findings did not reflect the trend from the constituency polls - a JLP lead. But is this a valid expectation? Can poll findings in five constituencies out of 60 reflect the national political situation?
The answer is no, because these five constituencies are not a representative sample of the entire 60. No attempts should be made to generalise a particular constituency poll finding. There is an exception to this rule which we will address later in this article.
Furthermore, based on the rules of research, the size of the sample (480) used in the constituency polls carries a larger margin of error - five per cent - compared to three per cent for the sample of 822 registered votes used in the national poll. This difference in error margin means the constituency polls are less accurate than the national poll with its smaller error margin. So, any comparison of the constituency poll findings with the national poll results is like comparing apples and breadfruit.
On the matter of margin of error, readers need to interpret poll results bearing this statistic in mind. Let me explain. When the margin of error of three per cent is applied to the PNP's popular standing of 34 per cent as captured by Johnson's recent national poll, the figure could increase or decrease by as much as three per cent in an actual election.
So, conceivably, the poll findings in the constituencies in which Johnson found the JLP leading could shift up or down by the five per cent margin of error in a real election as illustrated in the table.
Of course, movements within the error margin are not uniformed. Factors can affect the PNP and JLP simultaneously, and to different degrees, thus resulting in either party gaining or losing an advantage. In the cases of St. Andrew East, and Manchester Central, where both parties were in deadlock, any movement within the error margin could shift the balance of power.
Part of the difficulty readers expressed in response to the release of the party standings last Sunday was that the national poll results did not reflect the findings at the constituency levels. This is a misunderstanding on the part of some readers.
Pollster's credibility
The national poll results are not the aggregate of 60 mini-polls in constituencies. For the purpose of conducting a national survey, the island becomes one big constituency with respondents drawn from a wide cross-section of areas to ensure the sample is representative. This approach helps to minimise bias from, for example, garrison constituencies or political enclaves.
The credibility of pollster Bill Johnson was also called into question last week. Critics pointed to the variance in his poll findings related to the outcome of the general election in St. Lucia last year.
Close to election day, in an attempt to influence supporters, the ruling party of then Prime Minister Kenny Anthony released poll findings by Johnson indicating that the party was ahead of the opposition party in popular support. But, the ruling party subsequently lost the election six seats to the opposition's 11, while both parties tied for popular support.
Johnson explains that he had conducted a series of polls for the ruling party; and while the first of these showed the ruling party ahead of the opposition in popular support, the latter polls showed the party rapidly losing voter support. In fact, Johnson says, his last poll had accurately predicted a tie in popular votes for each party.
One lesson from the St. Lucian election for us is that the popular vote split does not directly reflect the pattern of voting in constituencies.
As mentioned earlier, there are instances where poll findings in particular constituencies are used to predict generalised outcomes. But, in fact, the prediction is based on historical patterns from actual election outcomes.
For example, St. Elizabeth SW has always gone to the party that forms the government after an election since Independence. Political scientists describe this as a weather-vane seat because it signals the direction of the political winds of change.
Hence, the importance of The Gleaner's probing of the electoral situation in a seat like St. Elizabeth SW. The findings there and in similar-type seats point to the likely national winner of the next general election.
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