The UK General Election of 2015 - Institute for Governance and … · 2015-04-27 · The UK general...
Transcript of The UK General Election of 2015 - Institute for Governance and … · 2015-04-27 · The UK general...
The UK General Election of 2015
Patrick Dunleavy
Briefing for Institute of Governance and Policy Analysis seminar,
University of Canberra, 23 April 2015
The 2015 party system, in England
Conservative
centre
Labour Lib
Dems
BNP Greens
UKIP
left right
Respect
Current party performance across both
party systems
Polling averages as at 27 April, 2015, last six polls
Will the 2015 general election mark the ‘bitter end’ for political scientists’
Belief in Duverger’s Law?
Duverger’s Law in full effect: US House of Representatives election, 2006
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Republican lead over Democrats in each electoral district
To
tal v
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r a
ll o
the
r p
art
ies
in
ea
ch
ele
cto
ral d
istr
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Double APT
Crown
Republicans ahead of DemocratsDemocrats ahead of Republicans
67%67%
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Conservatives lead over Labour in each local seat (%)
To
tal v
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sh
are
fo
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ll o
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r p
art
ies
(%
)
Conservative MPs
with a local majority
Labour MPs with
a local majority
Other MPs
with a local
majority
Duverger’s Law working pretty well: the general election, Great Britain 1955
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Conservative lead over Labour in each local seat (%)
To
tal vo
te s
hare
fo
r all o
ther
part
ies in
each
seat
(%)
Labour MPs with
a local majority
Conservative MPs
with a local majority
Other MPs
with a local
majority
67% 67%
Duverger’s Law not working at all: the general election, Great Britain 2010
The UK general election of 2010 and the coalition outcome
Party
Another
resource
% Votes
Key
resource
% of all
MPs
% coalitional
potential score
(normalized
Banzahf index)
Conservative 36.1 47.6 36.7
Labour 29.0 40.0 22.0
Liberal Democrat 23.0 8.8 22.0
Democratic Unionists 0.6 1.2 7.3
Scottish National Party 1.7 0.9 5.5
Plaid Cymru 0.6 0.5 1.8
Social Dem & Lab P
(NI) 0.4 0.5 1.8
Green 1.0 0.2 0.9
Alliance Party (NI) 0.1 0.2 0.9
Others (no seats) 7.5 0.2 0.9
Total 100% 100 % 100 %
Con share of Con + Lib Dem C score = 56%
Party Low CENTRAL High
CON 243 284 325
LAB 234 276 321
SNP 26 41 53
LIB DEM 15 25 35
Plaid Cymru 1 3 5
Greens 0 1 2
UKIP 0 1 1
The range of possible party MP numbers from Electionforecast.co.uk
Not shown: 18 Northern Ireland seats - An overall majority needs 323 seats
Party MPs % of MPs Coalitionality score %
CON 284 44.0 33.2
LAB 276 42.7 28.4
SNP 41 6.7 28.1
LIB DEM 25 3.9 2.6
Plaid Cymru 3 0.5 1
Greens 1 0.2 0.1
UKIP 1 0.2 0.1
Party coalitionality scores from MPs in Electionforecast.com central projection
Not shown: 18 Northern Ireland parties - An overall majority needs 323 seats
Party MPs % of MPs
Coalitionality score %
CON 288 44.6 36.7
LAB 263 40.7 23.3
SNP 51 7.9 23.3
LIB DEM 24 3.7 6.6
Plaid Cymru 3 0.5 1
Greens 1 0.2 0.1
UKIP 1 0.2 0.1
Party coalitionality scores from MPs in ElectionsEtc.com projection
Not shown: 18 Northern Ireland parties - An overall majority needs 323 seats
Who may have an overall majority & probabilities from ElectionsEtc.com team (Fisher)
Inner circle shows probability of being Largest party
Source: Elections etc.com
For more discussion on UK, see these LSE blogs:
http://blogs.lse.ac.uk/politicsandpolicy/
www.EUROPP.eu
www.DemocraticAudit.com