Online Appendix: Supplemental Information

Table SI1. Descriptive Statistics

Variable / Obs / Mean / Std. Dev. / Min / Max
PD members’ general opinion of primary elections / 10891 / .7380406 / .4397209 / 0 / 1
Membership style / 12669 / 1.398216 / .4895498 / 1 / 2
Party activity / 12630 / 2.464608 / 1.349218 / 1 / 6
Satisfaction with 2012 primary elections / 10556 / 2.468833 / .5549609 / 1 / 3
Winner & loser - 1 round / 11861 / .697496 / .4593616 / 0 / 1
Age / 13613 / 4.357746 / 1.344545 / 1 / 6
Education / 13666 / 3.359579 / .6845229 / 1 / 4
Left & right self-placement / 12727 / 1.582148 / .6804252 / 1 / 5
Interest in politics / 13205 / 3.815676 / .459785 / 1 / 4
Newspapers (freq) / 13205 / 4.686634 / .6381592 / 1 / 6
TV news (freq) / 13009 / 4.744638 / .7123973 / 1 / 6
Websites (freq) / 13009 / 3.815282 / 1.348805 / 1 / 6
Table SI2. Territorial composition of the sample (without foreign PD enrolled)
Regions / Members (%) / Valid answers (N) / Regional distribution (%) / Difference
Emilia-Romagna / 18.6 / 2430 / 17.9 / -0.7
Toscana / 12.2 / 1839 / 13.7 / +1.5
Lazio / 9.7 / 905 / 6.6 / -3.1
Lombardia / 8.4 / 2418 / 17.7 / +9.3
Campania / 8.2 / 141 / 1.0 / -7.2
Sicilia / 7.3 / 370 / 2.7 / -4.6
Puglia / 5.1 / 435 / 3.2 / -1.9
Umbria / 4.8 / 221 / 1.6 / -3.2
Calabria / 4.1 / 219 / 1.6 / -2.5
Veneto / 3.9 / 1397 / 10.2 / +6.6
Piemonte / 3.9 / 946 / 6.9 / +3.0
Marche / 3.1 / 303 / 2.2 / -0.9
Sardegna / 2.8 / 553 / 4.0 / +1.2
Liguria / 2.6 / 502 / 3.7 / +1.1
Abruzzo / 2.4 / 176 / 1.3 / -1.1
Friuli-Venezia Giulia / 1.4 / 415 / 3.0 / +1.6
Basilicata / 0.8 / 132 / 1.0 / +0.2
Trentino-Alto Adige / 0.4 / 220 / 1.6 / +1.2
Molise / 0.3 / 0 / 0 / -0.3
Valle d’Aosta / 0.1 / 18 / 0.1 / +0.1
N / 763,783 / 13,640 / 100 / -
Note. Data on membership refer to the 2011 enrolments. The whole sample includes also 26 PD members resident in foreign countries.
Table SI3. Socio-graphic profile by membership style (percentages)
Old-Style
Member / New-Style Member / Total
Gender
Women / 22.3 / 39.2 / 29.0
Men / 77.7 / 60.8 / 71.0
N / 7624 / 5045 / 12,669
Age
16-24 years / 0.6 / 6.4 / 2.9
25-34 years / 6.2 / 13.4 / 9.1
35-44 years / 11.5 / 15.4 / 13.1
45-54 years / 21.0 / 22.2 / 21.5
55-64 years / 36.7 / 25.9 / 32.4
over 65 years / 24.0 / 16.7 / 21.1
N / 7598 / 5026 / 12,624
Education
Primary School / 0.8 / 0.5 / 0.7
Middle school / 10.6 / 8.0 / 9.6
High school / 44.6 / 39.4 / 42.6
University/College / 44.0 / 52.1 / 47.2
N / 7624 / 5045 / 12,669
Profession
Retired / 32.2 / 22.9 / 28.5
Employee / 24.7 / 25.4 / 25.0
Freelance professional / 11.3 / 11.1 / 11.2
Executive (both in public and private sectors) / 9.5 / 7.6 / 8.7
Teacher / 5.3 / 7.3 / 6.1
Self Employee / 4.6 / 4.3 / 4.5
Student / 1.3 / 8.0 / 4.0
Unemployed / 2.8 / 4.3 / 3.4
Worker / 2.9 / 3.4 / 3.1
Businessman / 2.9 / 2.5 / 2.7
Housewife / 0.8 / 1.4 / 1.0
Other / 1.8 / 1.9 / 1.9
N / 7613 / 5031 / 12,644
Table SI4. Political profile by membership style (percentages)
Old-Style Member / New-Style Member / Total
Interest in politics
Not at all / 0.2 / 0.6 / 0.4
A little / 1.2 / 2.5 / 1.7
Somewhat / 10.2 / 17.9 / 13.3
Very / 88.4 / 79.0 / 84.6
N / 7624 / 5045 / 12,669
Previous Party
Communist party / 68.1 / - / 68.1
Catholic party / 22.8 / - / 22.8
Socialist party / 6.8 / - / 6.8
Post-materialist party / 1.6 / - / 1.6
Second Republic party / 0.3 / - / 0.3
Centre-right party / 0.4 / - / 0.4
N / 6895 / - / 6895
Ideological self-placement
Left / 53.2 / 47.8 / 51.0
Centre-left / 38.5 / 45.5 / 41.3
Centre / 6.9 / 5.7 / 6.4
Centre-right / 1.1 / 0.8 / 1.0
Right / 0.3 / 0.2 / 0.3
N / 7624 / 5045 / 12,669

Principal Component Analysis

Here below are reported the results of the exploratory factor analysis that has been performed in order to assess the presence of a latent variable dealing with the satisfaction with primaries and intra-party democracy behind all the items integrated in the scale. Three components were extracted with eigenvalues of more than one. The factors were rotated with both Varimax and Oblimin, obtaining essentially similar results (only the Varimax results are reported in the table). The first factor seems to reflect the evaluation by respondents of the functioning of internal democracy. The first Varimax factor accounted for about 32% of the total variance explained. The second factor represents the satisfaction more specifically with 2012 primaries, while the third one reflect the satisfaction with one’s role and contribution within the proceses of intra-party democracy. All in all, given that the three factors together explain 50% of the total variance and are highly correlated with each other, we consider that they refer to the more general concept of the satisfaction with intra-party democracy.

Table SI5. Explorative factor analysis of items measuring the satisfaction with primaries and internal democracy (rotated factor matrix).

Items / Factor
1 / 2 / 3
Bersani’s 2012 primary victory / -,077 / ,562 / ,150
The behavior of candidates defeated after the primaries / ,451 / -,120 / ,011
My personal contribution to the campaign / ,044 / ,005 / ,666
The relations with my party colleagues / ,148 / ,225 / ,709
The debate over the manifestos of candidates / ,488 / ,194 / ,360
The behavior of candidates during the campaign / ,664 / ,089 / ,062
The citizenship’s involvement capacity / ,538 / ,280 / ,120
The behavior of my party during the primaries organization / ,789 / ,212 / ,040

Note: Extraction Method: Principal Axis Factoring. Rotation Method: Varimax with Kaiser Normalization. Rotation converged in 4 iterations.

Table SI6. Correlation Matrix

Primary elections opinion / Membership style / Activity within the Party (weekly) / Satisfaction with 2012 primary elections / Internal-party Democracy Satisfaction / Winner & Loser - 1 round / Winner & Loser - 2 round / Age / Education / Left & Right self-placement (1-5) / Interest in politics (1-4) / Newspaper (freq) / TV news (freq) / Websites (freq) social networks
Primary elections opinion / 1
Membership style / 0.0590 / 1
Activity within the Party (weekly) / -0.0846 / -0.1131 / 1
Satisfaction with 2012 primary elections / 0.1833 / -0.0167 / 0.1642 / 1
Internal-party Democracy Satisfaction / 0.2249 / 0.0526 / 0.0196 / 0.3990 / 1
Winner & Loser - 1 round / 0.0034 / -0.0797 / 0.0978 / 0.2285 / 0.937 / 1
Winner & Loser - 2 round / 0.0122 / -0.0496 / 0.0588 / 0.2286 / 0.2908 / 0.786 / 1
Age / 0.0621 / -0.2221 / -0.2092 / -0.0099 / 0.0126 / 0.1369 / 0.1133 / 1
Education / -0.0156 / 0.0808 / 0.0050 / -0.0478 / -0.0975 / -0.0778 / -0.0555 / -0.2018 / 1
Left & Right self-placement (1-5) / -0.0363 / 0.0227 / -0.0388 / -0.1127 / -0.1093 / -0.2150 / -0.2586 / -0.0638 / 0.0338 / 1
Interest in politics (1-4) / -0.0134 / -0.1238 / 0.2300 / 0.0901 / -0.0054 / 0.0250 / 0.0194 / -0.0163 / 0.0676 / -0.0655 / 1
Newspaper (freq) / -0.0150 / -0.0894 / 0.0962 / 0.0200 / -0.0409 / 0.0283 / 0.0266 / 0.0972 / 0.0642 / -0.0363 / 0.1893 / 1
TV news (freq) / -0.0036 / -0.0654 / 0.0114 / 0.0196 / 0.0284 / 0.0809 / 0.0553 / 0.1930 / -0.1149 / -0.0125 / 0.0250 / 0.0231 / 1
Websites (freq) / -0.0242 / -0.0247 / 0.2270 / 0.0266 / -0.0696 / -0.0441 / -0.0528 / -0.1840 / 0.0388 / -0.0097 / 0.1677 / 0.1418 / 0.0156 / 1

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Table SI7. Primary elections and PD membership by age
Age 16-24 / Age 25-34 / Age 35-44 / Age 45-54 / Age 55-64 / Age >65
Dependent Variable: PD Members’ General Opinion of Primaries
Membership Style / 0.30
(0.38) / 0.38**
(0.14) / 0.51*** (0.12) / 0.20*
(0.10) / 0.29***
(0.09) / 0.26*
(0.12)
Activity within the Party / -0.08
(0.08) / -0.03
(0.05) / -0.12*** (0.04) / -0.10**
(0.03) / -0.14***
(0.03) / -0.13**
(0.05)
Constant / 0.69
(0.08) / 0.31
(0.30) / 0.43
(0.22) / 0.95***
(0.18) / 1.07***
(0.15) / 1.21***
(0.20)
LR chi2 / LR chi2 (2) 1.67 / LR chi2 (2) 8.60 / LR chi2 (2) 32.34 / LR chi2 (2)
15.11 / LR chi2 (2)
35.66 / LR chi2 (2)
16.36
Prob>chi2 / 0.44 / 0.01 / 0.00 / 0.00 / 0.00 / 0.00
Psuedo R2 / 0.00 / 0.01 / 0.02 / 0.01 / 0.01 / 0.01
Log-likelihood / -179.90 / -596.04 / -857.47 / -1361.14 / -1967.65 / -1169.10
N / 312 / 971 / 1421 / 2336 / 3545 / 2227
Notes. Models are logistic regressions (standard errors in parentheses). *<0.10, **<0.05, ***<0.01.

Table SI8. Primary elections and PD membership by education

<=Primary
school / Middle
school / High
school / University/
College
Dependent Variable: PD Members’ General Opinion of Primaries
Membership Style / -0.56
(0.66) / 0.13
(0.16) / 0.18**
(0.07) / 0.33***
(0.07)
Activity within the Party / 0.15
(0.28) / -0.02
(0.06) / -0.11***
(0.02) / -0.17***
(0.02)
Constant / 1.74
(1.15) / 1.08***
(0.30) / 1.06***
(0.13) / 0.98***
(0.12)
LR chi2 / LR chi2 (2)
1.04 / LR chi2 (2)
0.93 / LR chi2 (2) 30.75 / LR chi2 (2)
87.01
Prob>chi2 / 0.60 / 0.63 / 0.00 / 0.00
Psuedo R2 / 0.02 / 0.00 / 0.01 / 0.02
Log-likelihood / -31.55 / -545.72 / -2638.59 / -2952.19
N / 63 / 1008 / 4581 / 5194

Notes. Models are logistic regressions (standard errors in parentheses). *<0.10, **<0.05, ***<0.01.

Table SI9. Primary elections and PD membership by interest in politics

Not at all / A little / Somewhat / Very
Dependent Variable: PD Members’ General Opinion of Primaries
Membership Style / 0.37
(0.75) / 0.27
(0.37) / -0.29**
(0.13) / 0.33***
(0.05)
Activity within the Party / 0.21
(0.33) / -0.08
(0.23) / -0.19**
(0.07) / -0.14***
(0.02)
Constant / -0.36
(1.51) / 0.94
(0.75) / 1.92***
(0.26) / 0.94***
(0.09)
LR chi2 / LR chi2 (2)
0.54 / LR chi2 (2)
0.81 / LR chi2 (2) 10.22 / LR chi2 (2)
113.53
Prob>chi2 / 0.76 / 0.67 / 0.01 / 0.00
Psuedo R2 / 0.01 / 0.01 / 0.01 / 0.01
Log-likelihood / -23-71 / -93.93 / -774.90 / -5273.02
N / 37 / 176 / 1410 / 9223

Notes. Models are logistic regressions (standard errors in parentheses). *<0.10, **<0.05, ***<0.01.

Table S10A - Models omitting one region at a time. Dependent Variable: PD Members’ General Opinion of Primaries
Abruzzo / Basilicata / Calabria / Campania / Emilia-Romagna / Friuli-Venezia Giulia / Lazio / Liguria / Lombardia / Marche
Membership Style / 0.329*** / 0.334*** / 0.339*** / 0.328*** / 0.367*** / 0.332*** / 0.340*** / 0.318*** / 0.350*** / 0.335***
(0.0536) / (0.0536) / (0.0538) / (0.0536) / (0.0586) / (0.0541) / (0.0554) / (0.0541) / (0.0586) / (0.0540)
Activity within the Party / -0.175*** / -0.172*** / -0.170*** / -0.172*** / -0.168*** / -0.167*** / -0.175*** / -0.164*** / -0.172*** / -0.165***
(0.0196) / (0.0195) / (0.0196) / (0.0195) / (0.0215) / (0.0196) / (0.0202) / (0.0198) / (0.0211) / (0.0196)
2012 Primary Satisfaction / 0.849*** / 0.845*** / 0.845*** / 0.845*** / 0.871*** / 0.837*** / 0.831*** / 0.847*** / 0.842*** / 0.837***
(0.0473) / (0.0473) / (0.0475) / (0.0472) / (0.0517) / (0.0475) / (0.0485) / (0.0478) / (0.0511) / (0.0475)
Winner First Round / -0.229*** / -0.233*** / -0.230*** / -0.235*** / -0.238*** / -0.240*** / -0.207*** / -0.240*** / -0.286*** / -0.247***
(0.0569) / (0.0569) / (0.0571) / (0.0570) / (0.0621) / (0.0575) / (0.0582) / (0.0575) / (0.0617) / (0.0572)
Age / 0.106*** / 0.109*** / 0.109*** / 0.108*** / 0.113*** / 0.105*** / 0.113*** / 0.117*** / 0.120*** / 0.121***
(0.0207) / (0.0206) / (0.0207) / (0.0206) / (0.0224) / (0.0208) / (0.0212) / (0.0208) / (0.0225) / (0.0207)
Education / 0.00629 / 0.00565 / 0.0104 / 0.0138 / -0.0000367 / 0.0142 / 0.0142 / 0.0113 / -0.00115 / 0.0143
(0.0377) / (0.0377) / (0.0378) / (0.0377) / (0.0418) / (0.0379) / (0.0387) / (0.0381) / (0.0413) / (0.0379)
L-R Self-Placement / -0.101*** / -0.0906** / -0.0960** / -0.0938** / -0.119*** / -0.0891** / -0.109*** / -0.106*** / -0.110*** / -0.0928**
(0.0373) / (0.0374) / (0.0375) / (0.0376) / (0.0405) / (0.0377) / (0.0383) / (0.0376) / (0.0404) / (0.0375)
Interest in Politics / -0.0416 / -0.0322 / -0.0280 / -0.0428 / -0.0598 / -0.0435 / -0.0239 / -0.0494 / 0.0368 / -0.0262
(0.0637) / (0.0636) / (0.0637) / (0.0637) / (0.0693) / (0.0640) / (0.0652) / (0.0645) / (0.0682) / (0.0638)
Newspapers (freq) / -0.0268 / -0.0274 / -0.0331 / -0.0311 / -0.00571 / -0.0269 / -0.0323 / -0.0449 / -0.0447 / -0.0386
(0.0417) / (0.0415) / (0.0421) / (0.0416) / (0.0453) / (0.0418) / (0.0427) / (0.0421) / (0.0454) / (0.0421)
TV News (freq) / -0.0479 / -0.0483 / -0.0483 / -0.0474 / -0.0527 / -0.0435 / -0.0561 / -0.0499 / -0.0480 / -0.0539
(0.0368) / (0.0367) / (0.0368) / (0.0368) / (0.0403) / (0.0374) / (0.0383) / (0.0374) / (0.0410) / (0.0370)
Websites (freq) / 0.00357 / 0.0109 / 0.00847 / 0.00933 / 0.0111 / 0.0111 / 0.0146 / 0.00671 / 0.0107 / 0.00483
(0.0198) / (0.0198) / (0.0199) / (0.0198) / (0.0218) / (0.0200) / (0.0205) / (0.0200) / (0.0215) / (0.0199)
Constant / -0.703* / -0.748* / -0.750* / -0.725* / -0.827* / -0.742* / -0.721* / -0.616 / -0.962** / -0.752*
(0.397) / (0.397) / (0.399) / (0.397) / (0.432) / (0.401) / (0.410) / (0.403) / (0.433) / (0.399)
Observations / 9193 / 9233 / 9175 / 9216 / 7605 / 9033 / 8753 / 8989 / 7584 / 9109
Pseudo R-squared / 0.045 / 0.045 / 0.045 / 0.045 / 0.049 / 0.045 / 0.044 / 0.046 / 0.047 / 0.045
Notes. Standard errors in parentheses ="* p<0.10, ** p<0.05, *** p<0.01
Table S10B - Models omitting one region at a time. Dependent Variable: PD Members’ General Opinion of Primaries
Piemonte / Puglia / Sardegna / Sicilia / Toscana / Trentino-Alto Adige / Umbria / Valle d'Aosta / Veneto
Membership Style / 0.332*** / 0.327*** / 0.321*** / 0.328*** / 0.316*** / 0.336*** / 0.322*** / 0.332*** / 0.319***
(0.0552) / (0.0542) / (0.0542) / (0.0540) / (0.0578) / (0.0538) / (0.0538) / (0.0533) / (0.0559)
Activity within the Party / -0.170*** / -0.179*** / -0.170*** / -0.173*** / -0.176*** / -0.175*** / -0.172*** / -0.176*** / -0.172***
(0.0201) / (0.0199) / (0.0198) / (0.0197) / (0.0213) / (0.0196) / (0.0196) / (0.0194) / (0.0202)
2012 Primary Satisfaction / 0.839*** / 0.833*** / 0.836*** / 0.852*** / 0.878*** / 0.852*** / 0.848*** / 0.845*** / 0.842***
(0.0487) / (0.0481) / (0.0479) / (0.0477) / (0.0509) / (0.0474) / (0.0474) / (0.0470) / (0.0494)
Winner First Round / -0.259*** / -0.217*** / -0.246*** / -0.252*** / -0.159*** / -0.245*** / -0.234*** / -0.235*** / -0.232***
(0.0589) / (0.0576) / (0.0576) / (0.0575) / (0.0613) / (0.0572) / (0.0571) / (0.0566) / (0.0598)
Age / 0.107*** / 0.113*** / 0.110*** / 0.112*** / 0.108*** / 0.112*** / 0.109*** / 0.111*** / 0.106***
(0.0212) / (0.0209) / (0.0209) / (0.0208) / (0.0223) / (0.0206) / (0.0207) / (0.0205) / (0.0216)
Education / -0.0108 / 0.00146 / 0.00363 / 0.0201 / -0.00530 / 0.00301 / 0.00601 / 0.00645 / 0.0171
(0.0388) / (0.0382) / (0.0382) / (0.0380) / (0.0410) / (0.0379) / (0.0378) / (0.0375) / (0.0395)
L-R Self-Placement / -0.0974** / -0.0861** / -0.0965** / -0.0860** / -0.116*** / -0.0995*** / -0.0911** / -0.0965*** / -0.0764*
(0.0384) / (0.0379) / (0.0378) / (0.0377) / (0.0401) / (0.0375) / (0.0374) / (0.0371) / (0.0392)
Interest in Politics / -0.0259 / -0.0422 / -0.0370 / -0.0455 / -0.0499 / -0.0281 / -0.0430 / -0.0308 / -0.0301
(0.0646) / (0.0641) / (0.0643) / (0.0644) / (0.0708) / (0.0638) / (0.0644) / (0.0632) / (0.0661)
Newspapers (freq) / -0.0226 / -0.0290 / -0.0281 / -0.0238 / -0.0684 / -0.0317 / -0.0267 / -0.0292 / -0.0275
(0.0424) / (0.0424) / (0.0419) / (0.0418) / (0.0459) / (0.0417) / (0.0417) / (0.0414) / (0.0434)
TV News (freq) / -0.0698* / -0.0626* / -0.0552 / -0.0430 / -0.0593 / -0.0489 / -0.0553 / -0.0517 / -0.0424
(0.0386) / (0.0374) / (0.0372) / (0.0369) / (0.0399) / (0.0373) / (0.0371) / (0.0368) / (0.0383)
Websites (freq) / 0.0105 / 0.0117 / 0.00855 / 0.00452 / 0.0142 / 0.00706 / 0.00841 / 0.00614 / 0.00874
(0.0204) / (0.0200) / (0.0199) / (0.0199) / (0.0213) / (0.0199) / (0.0199) / (0.0197) / (0.0208)
Constant / -0.584 / -0.616 / -0.627 / -0.814** / -0.412 / -0.744* / -0.648 / -0.732* / -0.802*
(0.406) / (0.403) / (0.401) / (0.400) / (0.440) / (0.400) / (0.400) / (0.395) / (0.413)
Observations / 8668 / 9009 / 8949 / 9074 / 8079 / 9154 / 9167 / 9300 / 8342
Pseudo R-squared / 0.046 / 0.044 / 0.045 / 0.046 / 0.049 / 0.046 / 0.046 / 0.046 / 0.045
Notes. Standard errors in parentheses ="* p<0.10, ** p<0.05, *** p<0.01

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