David: once you have completed the methods and findings sections could you send it back to me, along with some recommendations of the main lines of argument that you want to push forward for our research contribution section (analysis and conclusions).

Could you note how our findings correspond to the nomination findings in the Starmer 2020 paper; and in our British Politics clusters paper (again for the 2019-24 PLP)?

Model Fit

Table 2: Model fit comparison
Bridget Phillipson
Lucy Powell
Bell Ribeiro-Addy
None
Model Pseudo R² AIC Pseudo R² AIC Pseudo R² AIC Pseudo R² AIC
all 0.477 465.334 0.514 398.075 0.702 157.215 0.385 389.002
all_step 0.429 421.216 0.472 362.090 0.817 82.057 0.336 357.366
personal 0.266 488.811 0.185 457.238 0.561 119.991 0.161 394.612
constituency 0.033 543.289 0.009 486.210 0.036 182.197 0.065 397.046
group 0.298 478.753 0.277 428.469 0.699 95.771 0.209 382.783
union 0.107 533.779 0.033 493.373 0.469 126.437 0.019 423.277
voting 0.218 490.185 0.226 427.833 0.503 114.334 0.074 402.542

Descriptive Stats

Personal Variables

Table 3: Personal variables
Characteristic Overall
N = 399
Bridget Phillipson
N = 175
Lucy Powell
N = 117
Bell Ribeiro-Addy
N = 24
None
N = 83
p-value1
gender




0.004
    F 185 (46%) 66 (38%) 68 (58%) 9 (38%) 42 (51%)
    M 214 (54%) 109 (62%) 49 (42%) 15 (63%) 41 (49%)
ethnic_mp




0.3
    0 335 (84%) 149 (85%) 101 (86%) 17 (71%) 68 (82%)
    1 64 (16%) 26 (15%) 16 (14%) 7 (29%) 15 (18%)
lgbt 56 (14%) 32 (18%) 10 (8.5%) 4 (17%) 10 (12%) 0.10
mp_final_relig




0.5
    None 173 (43%) 72 (41%) 53 (45%) 11 (46%) 37 (45%)
    Catholic 24 (6.0%) 11 (6.3%) 8 (6.8%) 2 (8.3%) 3 (3.6%)
    Christian 159 (40%) 74 (42%) 46 (39%) 7 (29%) 32 (39%)
    Hindu 2 (0.5%) 1 (0.6%) 1 (0.9%) 0 (0%) 0 (0%)
    Jewish 12 (3.0%) 8 (4.6%) 2 (1.7%) 0 (0%) 2 (2.4%)
    Muslim 17 (4.3%) 3 (1.7%) 5 (4.3%) 3 (13%) 6 (7.2%)
    Sikh 12 (3.0%) 6 (3.4%) 2 (1.7%) 1 (4.2%) 3 (3.6%)
lr_score 39.7 (18.8, 57.5) 40.4 (29.1, 54.9) 39.8 (31.0, 57.0) 31.1 (18.8, 41.2) 40.7 (26.2, 57.5) <0.001
position_in_government




<0.001
    Backbench 279 (70%) 102 (58%) 104 (89%) 24 (100%) 49 (59%)
    Government 120 (30%) 73 (42%) 13 (11%) 0 (0%) 34 (41%)
first_elected_by_parliament




<0.001
    Starmer 242 (61%) 134 (77%) 75 (64%) 4 (17%) 29 (35%)
    Corbyn 55 (14%) 18 (10%) 13 (11%) 9 (38%) 15 (18%)
    Miliband 38 (9.5%) 4 (2.3%) 15 (13%) 5 (21%) 14 (17%)
    1992–2010 64 (16%) 19 (11%) 14 (12%) 6 (25%) 25 (30%)
1 Fisher’s Exact Test for Count Data with simulated p-value (based on 2e+05 replicates); Kruskal-Wallis rank sum test

Constituency Variables

Table 4: Constituency variables
Characteristic Overall
N = 399
Bridget Phillipson
N = 175
Lucy Powell
N = 117
Bell Ribeiro-Addy
N = 24
None
N = 83
p-value1
constituency_type




<0.001
    Borough 209 (52%) 82 (47%) 54 (46%) 14 (58%) 59 (71%)
    County 190 (48%) 93 (53%) 63 (54%) 10 (42%) 24 (29%)
majority 0.10 (0.00, 0.31) 0.09 (0.00, 0.25) 0.10 (0.00, 0.30) 0.14 (0.05, 0.29) 0.12 (0.01, 0.31) 0.003
1 Fisher’s Exact Test for Count Data with simulated p-value (based on 2e+05 replicates); Kruskal-Wallis rank sum test

Groups Variables

Table 5: Groups variables
Characteristic Overall
N = 399
Bridget Phillipson
N = 175
Lucy Powell
N = 117
Bell Ribeiro-Addy
N = 24
None
N = 83
p-value1
co_operative_party 41 (10%) 24 (14%) 9 (7.7%) 1 (4.2%) 7 (8.4%) 0.3
blue_labour 7 (1.8%) 2 (1.1%) 1 (0.9%) 0 (0%) 4 (4.8%) 0.2
socialist_campaign_group 20 (5.0%) 0 (0%) 0 (0%) 17 (71%) 3 (3.6%) <0.001
tribune 60 (15%) 21 (12%) 20 (17%) 0 (0%) 19 (23%) 0.013
mission_champions 27 (6.8%) 18 (10%) 8 (6.8%) 0 (0%) 1 (1.2%) 0.022
labour_to_win_backed 194 (49%) 119 (68%) 30 (26%) 0 (0%) 45 (54%) <0.001
labour_growth_group 102 (26%) 74 (42%) 16 (14%) 0 (0%) 12 (14%) <0.001
labour_yimby 18 (4.5%) 7 (4.0%) 3 (2.6%) 0 (0%) 8 (9.6%) 0.11
labour_housing 8 (2.0%) 6 (3.4%) 0 (0%) 0 (0%) 2 (2.4%) 0.2
labour_rural_research_group 24 (6.0%) 12 (6.9%) 7 (6.0%) 2 (8.3%) 3 (3.6%) 0.7
sera 92 (23%) 51 (29%) 24 (21%) 2 (8.3%) 15 (18%) 0.046
labour_movement_for_europe 49 (12%) 32 (18%) 8 (6.8%) 2 (8.3%) 7 (8.4%) 0.017
get_britain_working_group 35 (8.8%) 24 (14%) 6 (5.1%) 0 (0%) 5 (6.0%) 0.022
living_standards_coalition 103 (26%) 47 (27%) 46 (39%) 1 (4.2%) 9 (11%) <0.001
parliamentary_black_caucus 7 (1.8%) 0 (0%) 0 (0%) 3 (13%) 4 (4.8%) <0.001
1 Fisher’s Exact Test for Count Data with simulated p-value (based on 2e+05 replicates)

Unions Variables

Table 6: Unions variables
Characteristic Overall
N = 399
Bridget Phillipson
N = 175
Lucy Powell
N = 117
Bell Ribeiro-Addy
N = 24
None
N = 83
p-value1
community 91 (23%) 49 (28%) 22 (19%) 1 (4.2%) 19 (23%) 0.028
gmb 75 (19%) 39 (22%) 24 (21%) 1 (4.2%) 11 (13%) 0.078
unison 59 (15%) 36 (21%) 10 (8.5%) 1 (4.2%) 12 (14%) 0.015
usdaw 56 (14%) 26 (15%) 15 (13%) 1 (4.2%) 14 (17%) 0.5
unite 97 (24%) 28 (16%) 32 (27%) 18 (75%) 19 (23%) <0.001
fbu 34 (8.5%) 5 (2.9%) 9 (7.7%) 15 (63%) 5 (6.0%) <0.001
cwu 41 (10%) 18 (10%) 10 (8.5%) 6 (25%) 7 (8.4%) 0.13
aslef 5 (1.3%) 2 (1.1%) 2 (1.7%) 0 (0%) 1 (1.2%)
0.9
musicians_union 14 (3.5%) 4 (2.3%) 5 (4.3%) 1 (4.2%) 4 (4.8%) 0.6
1 Fisher’s Exact Test for Count Data with simulated p-value (based on 2e+05 replicates)

Voting Variables

Table 7: Voting variables
Characteristic Overall
N = 399
Bridget Phillipson
N = 175
Lucy Powell
N = 117
Bell Ribeiro-Addy
N = 24
None
N = 83
p-value1
ass_suicide_3rd




0.053
    Yes 226 (57%) 106 (61%) 70 (60%) 9 (38%) 41 (49%)
    No 157 (39%) 65 (37%) 42 (36%) 15 (63%) 35 (42%)
    Abstain 16 (4.0%) 4 (2.3%) 5 (4.3%) 0 (0%) 7 (8.4%)
abortion_vote




0.039
    Yes 289 (72%) 133 (76%) 92 (79%) 15 (63%) 49 (59%)
    No 24 (6.0%) 8 (4.6%) 5 (4.3%) 2 (8.3%) 9 (11%)
    Abstain 86 (22%) 34 (19%) 20 (17%) 7 (29%) 25 (30%)
palestine_early_day_motion_may_2025 45 (11%) 6 (3.4%) 11 (9.4%) 20 (83%) 8 (9.6%) <0.001
welfare_rebels_first_amendment 121 (30%) 18 (10%) 64 (55%) 22 (92%) 17 (20%) <0.001
1 Fisher’s Exact Test for Count Data with simulated p-value (based on 2e+05 replicates)

Regression Models

Stepwise Model

Table 8: Regression model outputs
reg_original_bp_all_stepreg_original_lp_all_stepreg_original_br_all_stepreg_original_none_all_step
(Intercept)-2.19 ***-2.09    2.07   -2.15 ***
(0.36)   (1.50)   (2.98)  (0.49)   
genderM0.64 *  -0.99 ***4.35 **       
(0.25)   (0.29)   (1.60)         
ethnic_mp1              2.11   -1.55 *  
              (1.39)  (0.71)   
lgbt                           
                           
mp_final_religCatholic                    -1.34    
                    (0.72)   
mp_final_religChristian                    -0.44    
                    (0.32)   
mp_final_religHindu                    1.08    
                    (2.07)   
mp_final_religJewish                    -0.11    
                    (0.81)   
mp_final_religMuslim                    1.51    
                    (0.95)   
mp_final_religSikh                    2.40 *  
                    (1.02)   
lr_score       0.05    -0.25 **       
       (0.04)   (0.08)         
position_in_governmentGovernment       -0.97 *  -3.89          
       (0.39)   (2.57)         
first_elected_by_parliamentCorbyn-0.44    -0.55          1.04 *  
(0.39)   (0.54)         (0.45)   
first_elected_by_parliamentMiliband-1.81 ** 0.31          1.17 *  
(0.57)   (0.59)         (0.49)   
first_elected_by_parliament1992–2010-0.91 ** -0.98          1.69 ***
(0.35)   (0.54)         (0.42)   
constituency_typeCounty       0.64 *  0.92   -0.51    
       (0.32)   (0.93)  (0.31)   
majority       3.71    9.91          
       (2.66)   (5.99)         
co_operative_party0.74                 -0.60    
(0.41)                (0.47)   
blue_labour       -1.34    -1.74   1.63    
       (1.19)   (2.06)  (0.91)   
socialist_campaign_group-1.25    -3.59 *        -2.44    
(1.51)   (1.56)         (1.44)   
tribune       1.06 *  -4.13 *        
       (0.47)   (2.02)         
mission_champions       0.79          -1.21    
       (0.55)         (0.87)   
labour_to_win_backed0.86 ** -1.28 ***-8.69 *        
(0.27)   (0.32)   (3.40)         
labour_growth_group0.94 ** -0.64                 
(0.31)   (0.38)                
labour_yimby-1.29 *               2.01 ** 
(0.62)                (0.62)   
labour_housing1.29    -1.56                 
(1.00)   (1.81)                
labour_rural_research_group0.80    -1.30 *  -0.42          
(0.52)   (0.57)   (1.11)         
sera                           
                           
labour_movement_for_europe              3.84 *        
              (1.51)         
get_britain_working_group                           
                           
living_standards_coalition       0.96 ** -1.89   -0.73    
       (0.34)   (1.07)  (0.44)   
parliamentary_black_caucus                    5.12 ** 
                    (1.73)   
community                           
                           
gmb                           
                           
unison                    0.66    
                    (0.42)   
usdaw              0.14          
              (1.24)         
unite              0.56          
              (0.79)         
fbu              4.97 **       
              (1.65)         
cwu                           
                           
aslef              -7.78 *        
              (3.83)         
musicians_union-0.91           1.90          
(0.69)          (1.52)         
ass_suicide_3rdNo                           
                           
ass_suicide_3rdAbstain                           
                           
abortion_voteNo              0.72   1.15 *  
              (1.37)  (0.55)   
abortion_voteAbstain              0.43   0.47    
              (0.90)  (0.36)   
palestine_early_day_motion_may_2025No       0.94                 
       (0.54)                
welfare_rebels_first_amendmentNo1.64 ***-1.79 ***-1.15   0.76 *  
(0.32)   (0.34)   (0.77)  (0.37)   
N399       399       399      399       
AIC421.22    362.09    82.06   357.37    
BIC477.06    441.87    165.83   449.11    
Pseudo R20.43    0.47    0.82   0.34    
*** p < 0.001; ** p < 0.01; * p < 0.05.

Variable Importance

Table 9: Top 5 variables by importance
fullname variable overall estimate p.value
Bridget Phillipson welfare_rebels_first_amendmentNo 5.097 1.6415654 0.000
Bridget Phillipson labour_to_win_backed 3.219 0.8554719 0.001
Bridget Phillipson first_elected_by_parliamentMiliband 3.205 -1.8138054 0.001
Bridget Phillipson labour_growth_group 3.049 0.9407903 0.002
Bridget Phillipson first_elected_by_parliament1992–2010 2.587 -0.9120321 0.010
Lucy Powell welfare_rebels_first_amendmentNo 5.250 -1.7853358 0.000
Lucy Powell labour_to_win_backed 4.001 -1.2751249 0.000
Lucy Powell genderM 3.400 -0.9894009 0.001
Lucy Powell living_standards_coalition 2.811 0.9583399 0.005
Lucy Powell position_in_governmentGovernment 2.525 -0.9722982 0.012
Bell Ribeiro-Addy lr_score 3.036 -0.2470813 0.002
Bell Ribeiro-Addy fbu 3.014 4.9728669 0.003
Bell Ribeiro-Addy genderM 2.712 4.3473726 0.007
Bell Ribeiro-Addy labour_to_win_backed 2.558 -8.6931880 0.011
Bell Ribeiro-Addy labour_movement_for_europe 2.546 3.8388726 0.011
None first_elected_by_parliament1992–2010 4.025 1.6856054 0.000
None labour_yimby 3.237 2.0050919 0.001
None parliamentary_black_caucus 2.952 5.1208789 0.003
None first_elected_by_parliamentMiliband 2.381 1.1703035 0.017
None mp_final_religSikh 2.363 2.3991038 0.018

MPs and CLP