Nigel Marriott Profile picture
Independent statistician using data to understand our world & to predict the future. Currently focused on pay gaps, diversity, elections, forecasting, surveys.
Mike Taylor Profile picture 1 added to My Authors
May 8, 2021 8 tweets 4 min read
Dan Norris has won #WestOfEnglandMayor for #Labour making it one of the few LAB gains in #LocalElections2021.

In doing so, he also wrecked my forecast (see the Conservatives would just hold on!

So what went wrong?


@adam_ldr @StephenSumner15

/1 ... blog makes it clear that my forecast was in fact the minimum CON needed to do to win & was based on a number of assumptions.

The final vote tally saw LAB with 40k votes ahead of CON & crunching the numbers breaks the reason for this into 4 parts.

First an aside.

May 8, 2021 8 tweets 4 min read
WECA Mayor count takes place today covered by @adam_ldr @StephenSumner15

I've updated my forecast based on the PCC counts yesterday (Orig FC here PCC had an IND candidate but WECA doesn't.

My FC of 1st prefs is unchanged, CON lead by 5pts.

But ... /1 ... PCC saw 51% of eliminated candidates votes passed to LAB & CON as 2nd prefs.

This is high for an SV election.

I haven't any other SV election exceed 43%. Normally it's less than 40%.

Reason appears to be twofold.

Bristol T/O was higher than expected (54% of WECA) ...

May 7, 2021 10 tweets 5 min read
What is the lesson from #HartlepoolByElection for forecasting future elections?

I have 2 hypotheses.

1. Hartlepool was behind the curve in #GE2019 & the by-election represents catch up.
2. #Brexit realignment of British politics is still continuing.

Let's look at them... /1 The 1st can be confirmed just by looking at CON vote share changes between 2010 & 2019 in Hartlepool's 4 neighbours.

Easington > from 14% to 26%
Sedgefield > from 23% to 47%
Stockton N > from 26% to 41%
Redcar > from 14% to 46%
Hartlepool > from 28% to 29%

So the jump ...

Nov 3, 2020 11 tweets 6 min read
Parliament votes tomorrow to confirm that England will go into its 2nd #COVID19 lockdown from Thursday. Does the data show that it's necessary?

We know that deaths are rising and at present are on trend to overtake the April peak around the 3rd/4th week of November.

But ...1/n ... if cases are already in decline by now, then what will a 2nd lockdown do to help reduce deaths?

At best all it can do is accelerate an existing decline or at worse prevent cases from increasing again.

So are cases about to turn? Nationally, the picture is poised. /2
Nov 3, 2020 12 tweets 3 min read
#USPresidentialElections2020 today so I thought I would list some facts and figures you might not be aware of.

This the 59th presidential election in USA and the 56th competitive one.

3 elections saw a candidate elected unopposed 1789, 1792, 1820.

Of the 55 competitive elections, 36 saw the winner win a majority of both the electoral college (EC) & popular vote (PV).

One, 1800, needed a contingent election in the House of Representatives as well, an oddity that led to the 12th Amendment that could play a part in 2020.

Feb 13, 2020 24 tweets 14 min read
If this goes viral, I'm claiming the credit for the hashtag!

The #stats behind "Moving to a world beyond p<0.05" should be called #Pexit.

Yes there are parallels between #Pexit & #Brexit as I will explain! /1 First look at the timing.

March 2016 - ASA statement on misuse of p-values

June 2016 - The UK votes to leave the EU

They were preceded by decades of debate on the use & misuse of P-values & the UK's relationship with the EU.

Dec 1, 2019 8 tweets 4 min read
Are we going to see a repeat of #GE2017 ? In my Friday post… summarising latest poll trends, I said Labour need to focus on C2DE, Leavers & Lib Dems.

With the polls we've had over the weekend, this thread summarises what I am seeing. /1 CON-LAB lead is unchanged from the start of the election since both LAB & CON are up 7 pts. If this remains the case, it will be a Conservative majority.

Note figures for the latest week includes some from end of last week. My week is defined to be Thurs-Weds. /2
Nov 29, 2019 6 tweets 5 min read
My #GE2019 poll tracker is now up to date on my blog here

As before, I've compared latest polls to election results from GE74 to #GE17 & broken the data down by region, #GE2017, #Brexit & class.

Full details in the blog but here are the key pts. /1 #ConservativeParty are back to #GE2017 levels in all regions. Votes are being redistributed from remainers to leavers and the key to a majority is the efficiency of this transfer. /2
Nov 28, 2019 4 tweets 3 min read
Some excellent points here.

MRP is simply a cleverer model for turning voting intention data into seats.

If you have incorrect polling data, it will cleverly turn that into incorrect seats with more precision.

I had a clever model in #GE17 and look how that turned out! /1 I am not a pollster and so had to rely on published polls that turned out to be wrong in the North & Midlands.

Had the polls been right, my seat forecast would have been near perfect as I demonstrated in my post mortem.… /2
May 29, 2019 7 tweets 3 min read
OK, if you want to follow the #conservativeleadership race, here is a summary of the declared candidates so far. I've done this as a #Diversity analysis i.e. how much they differ from the norm but I also found it a very good way of getting to know their backgrounds @sundersays /1 Nominations close on June 10th so if people are interested, I will keep this up to date. Once the nominees are known, I will switch to a political summary instead e.g. voting record, years as MP, etc /2
Jan 13, 2019 19 tweets 7 min read
How can Corbyn get into Downing St at the next election if one comes soon? Here is my thread looking at what needs to change from the 2017 #GeneralElection when #Labour won 262 seats. /1 To become the largest party, Labour needs to gain around 30 seats. It so happens that there are 29 seats where Labour is in 2nd place less than 3 pts behind the incumbent. 21 are held by the #CONSERVATIVES, 7 by the SNP, 1 by #plaidcymru. /2