PPBS

System Justification [2018]

A Politico-Psychological Analysis

Report generated

March 23, 2026

1 Study Characteristics

1.1 Items: System Justification

1.2 Sample

N=TBD

Sample description for the 2018 PPBS CINT Post-election study to be added.

2 Descriptives

2.1 Means, SD, Range, & SE

Table 1: Descriptives
Descriptives for System Justification Items
mean sd median se
SJ1 4.82 2.15 5.00 0.04
SJ2 4.93 2.22 5.00 0.04
SJ3 4.57 2.27 5.00 0.04
SJ4 6.65 2.40 7.00 0.05
SJ5 5.64 2.10 6.00 0.04
SJ6 5.15 2.63 5.00 0.05
SJ7 4.03 2.13 4.00 0.04
SJ8 4.65 2.12 5.00 0.04
Mean 5.05 1.51 5.12 0.03
Note:
All items: n = 2759, min = 1, max = 9. Mean: min = 1, max = 9

2.2 Response Distribution

Figure 1: Proportion of each response categories for System Justification Items
Figure 2: Distribution of reponses for System Justification Items

2.3 Correlations

Figure 3: Bivariate Spearman’s correlations for System Justification

Note. Upper triangle shows Spearman’s rank-order correlations. *** p < .001, ** p < .01, * p < .05.

Figure 4: Bivariate Spearman’s correlations for System Justification

Note. Upper triangle shows Spearman’s rank-order correlations by party identity. *** p < .001, ** p < .01, * p < .05.

Figure 5: Correlation Matrix of System Justification items, Spearman’s rank correlations

3 Demographics

3.1 Social Class

Figure 6: System Justification as grouped by SES
Figure 7: Raincloud Plots showing System Justification grouped by Social Class

Note on the Raincloud Plots

  • Statistical summary (top): Welch’s t-test (or ANOVA) results, effect size, confidence intervals, p-values, and sample sizes are shown above each plot.
  • Bayesian analysis (bottom): Log Bayes factor and credible intervals are reported below each plot.
Table 2: System Justification as grouped by SES
SES N Mean SD
Poor 116 -0.45 1.13
Lower Middle Class 470 -0.21 0.99
Middle Middle Class 1249 0.06 0.97
Upper Middle Class 924 0.08 1.00

3.2 Gender

Figure 8: System Justification as grouped by Gender
Figure 9: Raincloud Plots showing System Justification grouped by Gender
Table 3: System Justification as grouped by Gender
System Justification as grouped by Gender
Gender N Mean SD
Female 1370 -0.09 0.97
Male 1389 0.09 1.02

3.3 Age

Figure 10: System Justification as grouped by Age
Figure 11: Raincloud Plots showing System Justification grouped by Age
Table 4: System Justification as grouped by Age
System Justification as grouped by Age
Age N Mean SD
18-24 years 295 -0.49 0.99
25-34 years 494 -0.29 1.06
35-44 years 451 -0.12 0.96
45-54 years 458 0.06 0.93
55-64 years 470 0.20 0.96
NA 591 0.38 0.87

3.4 Education

Figure 12: System Justification as grouped by Education
Figure 13: Raincloud Plots showing System Justification grouped by Education
Table 5: System Justification as grouped by Education
Education N Mean SD
Less than High School 312 -0.12 1.05
High School 767 0.05 0.94
Some College 779 0.00 1.03
Bachelor or higher 901 0.00 1.01

3.5 Income Levels

Figure 14: System Justification as grouped by Income Levels
Figure 15: Raincloud Plots showing System Justification grouped by Income Levels
Table 6: System Justification as grouped by Income Levels
System Justification as grouped by Income Levels
Income Levels N Mean SD
Less than $15,000 310 -0.28 1.04
$15,000-$24,999 275 -0.18 1.06
$25,000-$34,999 260 -0.15 0.98
$100,000-$149,999 384 0.02 0.99
$35,000-$49,999 351 0.04 0.97
$75,000-$99,999 355 0.08 0.92
$50,000-$74,999 495 0.13 0.99
$150,000 + 329 0.21 0.98

3.6 Ethnicity

Figure 16: System Justification as grouped by Ethnicity

Note on the Okabe-Ito color palette. The Okabe-Ito color palette (seen above) is a set of colorblind-friendly categorical colors available in R. We are using this palette for graphs with non-ordered variables (e.g., groups, categories) for accessibility.

Figure 17: Raincloud Plots showing System Justification grouped by Ethnicity
Table 7: System Justification as grouped by Ethnicity
System Justification as grouped by Ethnicity
Ethnicity N Mean SD
Black/African American 501 -0.32 0.98
Asian/Pacific Islander 87 -0.02 0.98
Native American 14 -0.23 1.06
Other 35 -0.89 1.07
NA 1976 0.12 0.97
NA 140 -0.23 1.01
NA 6 0.32 0.93

3.7 Occupation

Figure 18: System Justification as grouped by Occupation
Figure 19: Raincloud Plots showing System Justification grouped by Occupation
Table 8: System Justification as grouped by Occupation
System Justification as grouped by Occupation
Occupation N Mean SD
Employed 1334 -0.04 1.00
Retired 634 0.35 0.89
Unemployed 273 -0.14 0.99
Parent 126 -0.08 0.87
Disabled 201 -0.32 1.07
Student 153 -0.43 1.04
Full-time caregiver 38 0.12 0.99

3.8 Area

Figure 20: System Justification as grouped by Area
Figure 21: Raincloud Plots showing System Justification grouped by Area
Table 9: System Justification as grouped by Area
System Justification as grouped by Area
Area N Mean SD
Urban 723 -0.11 1.03
Rural 658 0.02 1.00
NA 1378 0.05 0.98

3.9 Religious Affiliation

Figure 22: System Justification as grouped by Religious Affiliation
Figure 23: Raincloud Plots showing System Justification grouped by Religious Affiliation
Table 10: System Justification as grouped by Religion
System Justification as grouped by Religious Affiliation
Religious Affiliation N Mean SD
Catholic 573 0.28 0.92
Protestant 1237 0.15 0.92
Jewish 72 0.09 1.07
Muslim 22 -0.50 1.18
Atheist/Agnostic 420 -0.54 1.03
Don't know / refused 435 -0.27 1.01

3.10 Section Summary

  System Justification
Predictors Estimates CI p
(Intercept) 3.64 3.39 – 3.90 <.001
Age 0.26 0.23 – 0.29 <.001
Income 0.10 0.07 – 0.13 <.001
Education -0.13 -0.19 – -0.08 <.001
Gender (Male) 0.23 0.12 – 0.34 <.001
Observations 2759
R2 / R2 adjusted .107 / .106

4 Political Behavior

4.1 Political Orientation

Figure 24: Political Orientation
Figure 25: Political Orientation (Controlled for Demographics)

Note. The y-axis shows residuals after regressing the outcome on demographics (Age, Income, Education, Gender). This illustrates how much the focal construct explains beyond demographic factors.

Figure 26: Correlation Matrix - Political Orientation
Table 11: Models of Political Orientation (SPRI) & System Justification
  Political Orientation Social Political Orientation Economic Political Orientation
Predictors Estimates CI p Estimates CI p Estimates CI p
(Intercept) 51.52 50.49 – 52.55 <.001 49.15 48.02 – 50.27 <.001 54.08 53.01 – 55.14 <.001
System Justification 11.21 10.18 – 12.25 <.001 11.34 10.22 – 12.46 <.001 11.50 10.44 – 12.57 <.001
Observations 2759 2759 2759
R2 / R2 adjusted .141 / .141 .124 / .124 .140 / .140
Table 12: Models of Ideology and System Justification with Controls
  Political Orientation Social Political Orientation Economic Political Orientation
Predictors Estimates CI p Estimates CI p Estimates CI p
(Intercept) 13.51 7.96 – 19.05 <.001 14.85 8.84 – 20.87 <.001 9.62 3.90 – 15.33 .001
System Justification 6.91 6.19 – 7.63 <.001 6.91 6.13 – 7.69 <.001 7.01 6.27 – 7.75 <.001
Age 0.97 0.32 – 1.62 .003 1.55 0.85 – 2.26 <.001 0.92 0.25 – 1.59 .007
Income 0.93 0.42 – 1.44 <.001 0.50 -0.05 – 1.05 .076 1.30 0.77 – 1.82 <.001
Education -2.72 -3.84 – -1.60 <.001 -4.02 -5.24 – -2.81 <.001 -1.69 -2.84 – -0.53 .004
Gender (Male) 1.83 -0.23 – 3.89 .082 1.68 -0.55 – 3.92 .140 2.82 0.69 – 4.94 .009
Observations 2759 2759 2759
R2 / R2 adjusted .152 / .151 .142 / .140 .152 / .150

4.2 Partisanship

Figure 27: Party Identity
Table 13: Mean System Justification by Party Identity
Mean System Justification by Party Identity (raw means)
Party Identity N Mean SD
Democrat 1100 4.66 1.46
Republican 819 5.82 1.30
Don't Know/Other 104 4.28 1.44
Independent/Moderate 736 4.90 1.48
Table 14: Model of System Justification & Party Identity (7-point)
  System Justification
Predictors Estimates CI p
(Intercept) 4.07 3.94 – 4.21 <.001
Party Identity (7-point) 0.29 0.26 – 0.32 <.001
Observations 1919
R2 / R2 adjusted .147 / .146
Table 15: Model of System Justification & Party Identity with Controls
  System Justification
Predictors Estimates CI p
(Intercept) 3.13 2.83 – 3.44 <.001
Party Identity (7-point) 0.25 0.22 – 0.28 <.001
Age 0.22 0.18 – 0.26 <.001
Income 0.04 0.01 – 0.07 .009
Education -0.09 -0.15 – -0.02 .010
Gender (Male) 0.20 0.08 – 0.32 .001
Observations 1919
R2 / R2 adjusted .210 / .208

4.3 Religiosity

Figure 28: Religiosity
Figure 29: Religiosity (Controlled for Demographics)

Note. The y-axis shows residuals after regressing the outcome on demographics (Age, Income, Education, Gender). This illustrates how much the focal construct explains beyond demographic factors.

Figure 30: Religiosity - Correlation Matrix

4.4 Candidate Preferences

Figure 31: Candidate Preferences
Table 16: Candidate Preferences (centered)
Candidate Preferences and System Justification [centered]
Candidate Preference N Mean SD
Donald Trump 770 0.50 0.88
Hillary Clinton 714 -0.12 0.95
Bernie Sanders 592 -0.59 0.95
None 243 -0.27 0.85
John Kasich 88 0.49 0.78
Ted Cruz 83 0.44 0.75
Ben Carson 82 0.36 0.87
Jeb Bush 44 0.40 0.66
Gary Johnson 43 -0.08 0.90
Marco Rubio 38 0.50 0.76
Jill Stein 32 -0.95 0.93
Rand Paul 30 0.24 1.13
Table 17: Candidate Preferences (raw means)
Candidate Preferences and System Justification [raw means]
Candidate Preferences N Mean SD Range
Donald Trump 770 5.81 1.32 1-9
Hillary Clinton 714 4.87 1.43 1-9
Bernie Sanders 592 4.16 1.43 1-9
None 243 4.64 1.28 1-9
John Kasich 88 5.79 1.18 1-9
Ted Cruz 83 5.71 1.13 1-9
Ben Carson 82 5.60 1.31 1-9
Jeb Bush 44 5.66 1.00 1-9
Gary Johnson 43 4.94 1.36 1-9
Marco Rubio 38 5.80 1.15 1-9
Jill Stein 32 3.61 1.41 1-9
Rand Paul 30 5.41 1.70 1-9

4.5 Party Preferences

Figure 32: Party Preferences
Table 18: Party Preferences (centered)
Party Preferences and System Justification [centered]
Party Preference N Mean SD
Green Party 68 -0.98 0.96
None 321 -0.32 0.93
Democrat Party 1251 -0.25 0.96
Libertarian Party 150 -0.07 0.95
Republican Party 898 0.51 0.83
Tea Party 71 0.55 1.03
Table 19: Party Preferences (raw means)
Party Preferences and System Justification [raw means]
Party Preferences N Mean SD Range
Green Party 68 3.58 1.45 1-9
None 321 4.57 1.40 1-9
Democrat Party 1251 4.67 1.45 1-9
Libertarian Party 150 4.95 1.44 1-9
Republican Party 898 5.82 1.26 1-9
Tea Party 71 5.88 1.56 1-9

4.6 Voting Preferences

Table 20: Voting Preferences
  2016 [Trump vs. Clinton] 2012 [Romney vs. Obama] 2008 [McCain vs. Obama]
Predictors Odds Ratios CI p Odds Ratios CI p Odds Ratios CI p
(Intercept) 48.64 33.75 – 70.94 <.001 72.11 48.45 – 108.84 <.001 57.91 39.34 – 86.38 <.001
System Justification 0.53 0.50 – 0.57 <.001 0.54 0.50 – 0.57 <.001 0.56 0.52 – 0.59 <.001
Observations 2759 2759 2759
R2 Tjur .155 .014 .133
Figure 33: Logistic Regression, System Justification & Voting Preferences

4.7 Voting & Party Identity

Table 21
Table 22: Supporters

4.8 Likeability

5 Politico-Psychological correlates of System Justification


5.1 Ideologies and Partisanship

Figure 34: Correlates - Ideologies and Partisanship (by magnitude)
Figure 35: Correlates - Ideologies and Partisanship (alphabetic)

5.2 Populism, Nationalism, Nativism, and Patriotism

Figure 36: Correlates - Populism, Nationalism, Nativism, and Patriotism (by magnitude)
Figure 37: Correlates - Populism, Nationalism, Nativism, and Patriotism (alphabetic)

5.3 Political Psychology

Figure 38: Correlates - Political Psychology (by magnitude)
Figure 39: Correlates - Political Psychology (alphabetic)



5.4 Positive and Negative correlates of System Justification

Figure 40: Correlates - Positive associations
Figure 41: Correlates - Positive associations (alphabetic)
Figure 42: Correlates - Negative associations
Figure 43: Correlates - Negative associations (alphabetic)

6 Elastic Net Analysis

Figure 44: Elastic net predicting System Justification: Political Psychology
Figure 45: Elastic net predicting System Justification: Ideology & Partisanship
Figure 46: Elastic net predicting System Justification: Demographics
Figure 47: Elastic net predicting System Justification: Attitudes
Figure 48: Elastic net predicting System Justification: Everything
Table 23: Elastic Net Summary
Elastic Net R² for predicting System Justification
Variable Group # Predictors R²
Political Psychology 4 .461
Ideology & Partisanship 5 .179
Demographics 5 .107
Attitudes 4 .125
Everything 18 .522
PPBS
Psychology of Political Behavior Studies PI: Flavio Azevedo