Despite the near constant news of Brexit and the parliamentary votes, the Conservatives appear to be holding steady at 40%.\u00a0 Labour’s slow downward trend resumed suddenly in February after months of relative stability.\u00a0 The most notable beneficiary was the Others which now includes The Independent Group (TIG) of MPs who left the Labour and Conservative party in February.\u00a0 It should be noted that I am using polls that do not explicitly suggest TIG as an option since they are not yet a formal political party.\u00a0 Polls that do suggest TIG are recording some significant vote shares so if and when TIG becomes a party, expect the Others to gain even more share in this chart.<\/p>\n
![\"\"](\"https:\/\/marriott-stats.com\/nigels-blog\/wp-content\/uploads\/2019\/03\/PollTracker-G1-2019-02-300x219.png\"){kind=tracking}
<\/p>\n
The net effect is that it is now Labour that has lost more share than the Conservatives since the 2017 election and the Conservatives now have a 6 point lead over Labour which would be enough for a majority if an election took place now.\u00a0 Under current seat boundaries, the Tories only need a 3 point lead for a majority.<\/p>\n
![\"\"](\"https:\/\/marriott-stats.com\/nigels-blog\/wp-content\/uploads\/2019\/03\/PollTracker-G2-2019-02-300x150.png\"){kind=tracking}
<\/p>\n
<\/p>\n
Poll Movements Over Last 12 Months<\/strong><\/span><\/h4>\nThis section takes a closer look at trends over the last 12 months.\u00a0 My goal is to discern any patterns that could be a portent of the future.<\/p>\n
Chart G4 shows daily movements and by eye, I can see 6 distinct periods labelled A, B, C, D, E & F.\u00a0 The exact dates of these periods are shown in table G6 later.\u00a0 Chart G5 has also been divided into the same 6 periods and this chart shows the Conservative lead over Labour.\u00a0 Briefly, the 6 periods can summarised as follows:-<\/p>\n
\n- A – A quiet period in the polls with little happening.\u00a0 At most a small drift from UKIP to the Conservatives allowing them to close the gap on Labour.<\/li>\n
- B – An anti-semitism controversy flares up in Labour which hits their poll ratings with some Labour voters defecting to the Lib Dems.\u00a0 The Conservatives take a lead over Labour.<\/li>\n
- C – The Chequers Brexit deal is announced and the controversy costs the Conservatives 3 points and Labour briefly regain their lead.\u00a0 UKIP are the main beneficiaries of the Conservative defections.<\/li>\n
- D – Another anti-semitism controversy flares up in Labour which costs them a point though they slowly recover that.\u00a0 The Conservatives make a slow recovery and the net effect is their 2 point lead is restored.<\/li>\n
- E – The EU withdrawal agreement is published and creates tremendous controversy.\u00a0 Parliament is wracked with debate and divisions and the Conservatives lead over Labour is eliminated.\u00a0 However, the picture is then unchanged for the next 3 months despite the parliamentary shenanigans.<\/li>\n
- F – 8 MPs leave the Labour and 3 leave the Conservative party to form TIG.\u00a0 One explicitly cites anti-semitism as her reasons for leaving and this issue is yet again news in the Labour party.\u00a0 Labour’s vote share drops noticeably with Others the main beneficiary.<\/li>\n<\/ul>\n
![\"\"](\"https:\/\/marriott-stats.com\/nigels-blog\/wp-content\/uploads\/2019\/03\/PollTracker-G4-2019-02-300x163.png\")
<\/p>\n
After 12 months of essentially static polls (despite the small movements I can tease out above), February saw a definite move in the polls with ![\"\"](\"https:\/\/marriott-stats.com\/nigels-blog\/wp-content\/uploads\/2019\/03\/PollTracker-G6-2019-02-300x189.png\")
Labour falling sharply and Others making gains.\u00a0 At the same time, the Conservative party has managed to maintain 40% despite the dominance of Brexit in the news and the various factions at play in Parliament<\/a>.\u00a0 As I said back in December, if the Tories can stop Brexit dominating the headlines, I can see them making further gains in the polls.\u00a0 Labour though appears to be in trouble with a clear downward trend and the obvious question is when will this hit bottom.\u00a0 History shows this tends to be the high twenties so there is still a way to go.\u00a0 \u00a0If this does happen, it will be interesting to see who benefits, TIG, Nationalists, Greens, Lib Dems?<\/p>\n <\/p>\n
Pollster House Effects<\/strong><\/span><\/h4>\nI have seen quite a bit of chatter over the last few months about house effect.\u00a0 A house effect occurs when one pollster is consistently showing different results to other pollsters.\u00a0 If that pollster also publishes more or less frequently than other pollsters and you are tracking a 9-poll rolling average like I do, then it is possible for my rolling average to be distorted by house effects.\u00a0 This is long overdue but I have finally taken a look at house effects and the results are very interesting.<\/p>\n
![\"\"](\"https:\/\/marriott-stats.com\/nigels-blog\/wp-content\/uploads\/2019\/03\/PollTracker-G7-2019-02-300x233.png\")
Over the last 6 months, the two most frequent pollsters have been YouGov & Opinium.\u00a0 It turned out that the other pollsters were very similar so in the graphic to the right, I have lumped all others into Others.\u00a0 As elsewhere, I have focused on the Conservative lead over Labour and there is no question that YouGov is giving more favourable results to the Conservatives than other pollsters.\u00a0 Opinium is largely in line with All Others.\u00a0 Since YouGov is the most frequent pollster, this implies my rolling averages shown in previous charts G1 to G6 could be showing a more favourable picture for the Tories overall.<\/p>\n
However, we must be very cautious in drawing a conclusion that YouGov is wrong.\u00a0 A house effect clearly exists but who is right and who is wrong?\u00a0 Only an election can answer that question but until then, I prefer to take an average across pollsters rather than favouring any particular pollster.\u00a0 The question I do need to ask myself is whether YouGov should be downweighted in my 9-poll rolling average since they poll more frequently?\u00a0 So far I have not done so and I am not yet convinced I need to do so.<\/p>\n
For a start, all pollsters are showing the same narrative of a largely stable picture for 5 months and then Labour losing votes in February.\u00a0 So changing my weights would not change the narrative which is the important bit.\u00a0 But there is also a subtle statistical reason for being cautious and that is whether pollsters are clones or different from each other.\u00a0 I will try and illustrate this point with a simplified example.<\/p>\n
Suppose YouGov and Opinium are the only pollsters and they each poll once a week.\u00a0 Then each month, we will have 4 polls from each pollster.\u00a0 Assume that a house effect exists and we don’t know who to favour, then clearly we would just take an average of the 8 polls.\u00a0 If for some reason, YouGov decided to poll twice weekly, then the existence of a house effect would justify giving each YouGov poll half the weight of an Opinium poll.<\/p>\n
Now suppose Opinium decide to poll once a month instead and 3 new pollsters enter the market also polling once a month.\u00a0 Let’s assume that the 4 monthly pollsters each do different weeks.\u00a0 Is this a different situation from my earlier scenario where YouGov & Opinium were the only pollsters and both did it weekly?\u00a0 The answer depends on whether the 3 new pollsters are effectively clones of Opinium because if they are then there is no justification for saying the situation has changed and you would still take a straight average of the 8 polls.\u00a0 On the other hand if the 3 new pollsters are not clones and generate their own house effects, then you would have grounds to say “we have 5 pollsters with house effects and one is polling more frequently than the other so downweight that pollster in your rolling average.”<\/p>\n
What table G7 is showing is that other pollsters are to all intents and purposes clones of Opinium.\u00a0 Yes there are more pollsters so perhaps YouGov are the outlier but even though YouGov are the most frequent pollster they still account for a minority of all polls.\u00a0 As far as I am concerned, downweighting YouGov will not have much impact in any case and I have no evidence that YouGov have fundamentally messed up their polling so for now I will continue with my straight 9-poll rolling average.\u00a0 I will keep the situation under review though.<\/p>\n
<\/p>\n
Voter Switching Patterns<\/span><\/strong><\/h4>\nI will update this section in a later post.<\/p>\n
<\/p>\n
Brexit Vote Dynamics<\/strong><\/span><\/h4>\nI will update this section in a later post.<\/p>\n
<\/p>\n
Regional Trends<\/strong><\/span><\/h4>\nFollowing the 2017 general election, I analysed why my forecast was in error by such a large margin<\/a>.\u00a0 I was able to show that the key error was that the opinion polls were not uniform in their underestimate of the Labour vote<\/a>.\u00a0 In the South and Scotland, the polls were broadly in line with the final results and my forecast was not that far out.\u00a0 However, in the North & Midlands the error was considerable which had a dramatic effect on my forecast.<\/p>\nGiven this error, it will be a while before I decide to update this section.<\/p>\n
<\/p>\n
Voter Demographics<\/span><\/strong><\/h4>\nI have no update to give this month.\u00a0 If you are interested in the question of whether there was a “Youthquake” in the 2017 General Election and what the effect of allowing 16 & 17 year olds to vote, then please read my Opinion Poll Tracker of March 2018<\/a>.<\/p>\n <\/p>\n
More Posts about Opinion Polls<\/strong><\/span><\/h4>\nSince the 2017 General Election when my forecast was undermined by yet another polling failure, I have written a number of posts about the long term accuracy of opinion polls and these are listed below:-<\/p>\n
\n- How accurate are the opinion polls in the UK?<\/a><\/li>\n
- Who is the most accurate pollster in the UK?<\/a><\/li>\n
- Do UK pollsters show forecasting skill?<\/a><\/li>\n
- My Welsh Barometer Poll forecast was a success!<\/a><\/li>\n<\/ol>\n
To see my previous Opinion Poll Trackers, please click the relevant month below.<\/p>\n
\n- 2018 – January<\/a>, March<\/a>, October<\/a>, December<\/a><\/li>\n
- 2017 – February<\/a>, March<\/a>, April<\/a>, May<\/a>, June (GE17)<\/a>, October<\/a>, November<\/a>, December<\/a><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"
After 12 months of essentially static polls despite the news being dominated by Brexit, Labour has experienced a significant worsening of their position and the Conservatives have opened up a lead over Labour that would give them a majority in parliament.\u00a0 Words of caution are being uttered about the extent of the Tory lead since […]<\/p>\n","protected":false},"author":3,"featured_media":1580,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[3],"tags":[58,33],"class_list":{"0":"post-1567","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-polling","8":"tag-opinion-poll-tracker","9":"tag-opinion-polls","10":"entry","11":"override"},"_links":{"self":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts\/1567","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/comments?post=1567"}],"version-history":[{"count":6,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts\/1567\/revisions"}],"predecessor-version":[{"id":1601,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts\/1567\/revisions\/1601"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/media\/1580"}],"wp:attachment":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/media?parent=1567"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/categories?post=1567"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/tags?post=1567"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
<\/p>\n
After 12 months of essentially static polls (despite the small movements I can tease out above), February saw a definite move in the polls with <\/p>\n I have seen quite a bit of chatter over the last few months about house effect.\u00a0 A house effect occurs when one pollster is consistently showing different results to other pollsters.\u00a0 If that pollster also publishes more or less frequently than other pollsters and you are tracking a 9-poll rolling average like I do, then it is possible for my rolling average to be distorted by house effects.\u00a0 This is long overdue but I have finally taken a look at house effects and the results are very interesting.<\/p>\n However, we must be very cautious in drawing a conclusion that YouGov is wrong.\u00a0 A house effect clearly exists but who is right and who is wrong?\u00a0 Only an election can answer that question but until then, I prefer to take an average across pollsters rather than favouring any particular pollster.\u00a0 The question I do need to ask myself is whether YouGov should be downweighted in my 9-poll rolling average since they poll more frequently?\u00a0 So far I have not done so and I am not yet convinced I need to do so.<\/p>\n For a start, all pollsters are showing the same narrative of a largely stable picture for 5 months and then Labour losing votes in February.\u00a0 So changing my weights would not change the narrative which is the important bit.\u00a0 But there is also a subtle statistical reason for being cautious and that is whether pollsters are clones or different from each other.\u00a0 I will try and illustrate this point with a simplified example.<\/p>\n Suppose YouGov and Opinium are the only pollsters and they each poll once a week.\u00a0 Then each month, we will have 4 polls from each pollster.\u00a0 Assume that a house effect exists and we don’t know who to favour, then clearly we would just take an average of the 8 polls.\u00a0 If for some reason, YouGov decided to poll twice weekly, then the existence of a house effect would justify giving each YouGov poll half the weight of an Opinium poll.<\/p>\n Now suppose Opinium decide to poll once a month instead and 3 new pollsters enter the market also polling once a month.\u00a0 Let’s assume that the 4 monthly pollsters each do different weeks.\u00a0 Is this a different situation from my earlier scenario where YouGov & Opinium were the only pollsters and both did it weekly?\u00a0 The answer depends on whether the 3 new pollsters are effectively clones of Opinium because if they are then there is no justification for saying the situation has changed and you would still take a straight average of the 8 polls.\u00a0 On the other hand if the 3 new pollsters are not clones and generate their own house effects, then you would have grounds to say “we have 5 pollsters with house effects and one is polling more frequently than the other so downweight that pollster in your rolling average.”<\/p>\n What table G7 is showing is that other pollsters are to all intents and purposes clones of Opinium.\u00a0 Yes there are more pollsters so perhaps YouGov are the outlier but even though YouGov are the most frequent pollster they still account for a minority of all polls.\u00a0 As far as I am concerned, downweighting YouGov will not have much impact in any case and I have no evidence that YouGov have fundamentally messed up their polling so for now I will continue with my straight 9-poll rolling average.\u00a0 I will keep the situation under review though.<\/p>\n <\/p>\n I will update this section in a later post.<\/p>\n <\/p>\n I will update this section in a later post.<\/p>\n <\/p>\n Following the 2017 general election, I analysed why my forecast was in error by such a large margin<\/a>.\u00a0 I was able to show that the key error was that the opinion polls were not uniform in their underestimate of the Labour vote<\/a>.\u00a0 In the South and Scotland, the polls were broadly in line with the final results and my forecast was not that far out.\u00a0 However, in the North & Midlands the error was considerable which had a dramatic effect on my forecast.<\/p>\n Given this error, it will be a while before I decide to update this section.<\/p>\n <\/p>\n I have no update to give this month.\u00a0 If you are interested in the question of whether there was a “Youthquake” in the 2017 General Election and what the effect of allowing 16 & 17 year olds to vote, then please read my Opinion Poll Tracker of March 2018<\/a>.<\/p>\n <\/p>\n Since the 2017 General Election when my forecast was undermined by yet another polling failure, I have written a number of posts about the long term accuracy of opinion polls and these are listed below:-<\/p>\n To see my previous Opinion Poll Trackers, please click the relevant month below.<\/p>\n After 12 months of essentially static polls despite the news being dominated by Brexit, Labour has experienced a significant worsening of their position and the Conservatives have opened up a lead over Labour that would give them a majority in parliament.\u00a0 Words of caution are being uttered about the extent of the Tory lead since […]<\/p>\n","protected":false},"author":3,"featured_media":1580,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[3],"tags":[58,33],"class_list":{"0":"post-1567","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-polling","8":"tag-opinion-poll-tracker","9":"tag-opinion-polls","10":"entry","11":"override"},"_links":{"self":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts\/1567","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/comments?post=1567"}],"version-history":[{"count":6,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts\/1567\/revisions"}],"predecessor-version":[{"id":1601,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/posts\/1567\/revisions\/1601"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/media\/1580"}],"wp:attachment":[{"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/media?parent=1567"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/categories?post=1567"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/marriott-stats.com\/nigels-blog\/wp-json\/wp\/v2\/tags?post=1567"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Labour falling sharply and Others making gains.\u00a0 At the same time, the Conservative party has managed to maintain 40% despite the dominance of Brexit in the news and the various factions at play in Parliament<\/a>.\u00a0 As I said back in December, if the Tories can stop Brexit dominating the headlines, I can see them making further gains in the polls.\u00a0 Labour though appears to be in trouble with a clear downward trend and the obvious question is when will this hit bottom.\u00a0 History shows this tends to be the high twenties so there is still a way to go.\u00a0 \u00a0If this does happen, it will be interesting to see who benefits, TIG, Nationalists, Greens, Lib Dems?<\/p>\nPollster House Effects<\/strong><\/span><\/h4>\n
Over the last 6 months, the two most frequent pollsters have been YouGov & Opinium.\u00a0 It turned out that the other pollsters were very similar so in the graphic to the right, I have lumped all others into Others.\u00a0 As elsewhere, I have focused on the Conservative lead over Labour and there is no question that YouGov is giving more favourable results to the Conservatives than other pollsters.\u00a0 Opinium is largely in line with All Others.\u00a0 Since YouGov is the most frequent pollster, this implies my rolling averages shown in previous charts G1 to G6 could be showing a more favourable picture for the Tories overall.<\/p>\nVoter Switching Patterns<\/span><\/strong><\/h4>\n
Brexit Vote Dynamics<\/strong><\/span><\/h4>\n
Regional Trends<\/strong><\/span><\/h4>\n
Voter Demographics<\/span><\/strong><\/h4>\n
More Posts about Opinion Polls<\/strong><\/span><\/h4>\n
\n
\n