{
  "alt": "Waterfall chart with five columns. The first is the 1978 mean rating of the other party, {fact:oth_1978}. The next three are steps: a fall of {fact:ss_oth_within_fall} for change within strength groups, a fall of {fact:ss_oth_comp_fall} for change in the mix of groups and a fall of {fact:ss_oth_inter_fall} for the interaction. The last column is the 2024 mean, {fact:oth_2024}. Buttons show the same decomposition with a face-to-face end point, with education groups and for the own-party rating.",
  "caption": "The bar for change within groups carries almost all of the fall; the bars for group mix and the interaction are small. Group mix is the change in each group's share of partisans, and the interaction is the part that comes from the shares and the group averages changing together.",
  "data": [
    {
      "conf_high": 48.8697,
      "conf_low": 47.121,
      "decomposition": "oth_strength",
      "kind": "start",
      "n": 1723,
      "step": "1978 mean",
      "value": 47.9954
    },
    {
      "conf_high": -23.2423,
      "conf_low": -25.782,
      "decomposition": "oth_strength",
      "kind": "delta",
      "n": 6803,
      "step": "Within groups",
      "value": -24.5364
    },
    {
      "conf_high": -1.26565,
      "conf_low": -2.31499,
      "decomposition": "oth_strength",
      "kind": "delta",
      "n": 6803,
      "step": "Group mix",
      "value": -1.77423
    },
    {
      "conf_high": -0.461375,
      "conf_low": -1.65367,
      "decomposition": "oth_strength",
      "kind": "delta",
      "n": 6803,
      "step": "Interaction",
      "value": -1.0548
    },
    {
      "conf_high": 21.4558,
      "conf_low": 19.804,
      "decomposition": "oth_strength",
      "kind": "end",
      "n": 5080,
      "step": "2024 mean",
      "value": 20.6299
    },
    {
      "conf_high": 48.8697,
      "conf_low": 47.121,
      "decomposition": "oth_strength_ftf",
      "kind": "start",
      "n": 1723,
      "step": "1978 mean",
      "value": 47.9954
    },
    {
      "conf_high": -18.0136,
      "conf_low": -22.4559,
      "decomposition": "oth_strength_ftf",
      "kind": "delta",
      "n": 2683,
      "step": "Within groups",
      "value": -20.2461
    },
    {
      "conf_high": -0.5121,
      "conf_low": -1.6308,
      "decomposition": "oth_strength_ftf",
      "kind": "delta",
      "n": 2683,
      "step": "Group mix",
      "value": -1.05213
    },
    {
      "conf_high": -0.204078,
      "conf_low": -2.1917,
      "decomposition": "oth_strength_ftf",
      "kind": "delta",
      "n": 2683,
      "step": "Interaction",
      "value": -1.18174
    },
    {
      "conf_high": 27.3504,
      "conf_low": 23.6803,
      "decomposition": "oth_strength_ftf",
      "kind": "end",
      "n": 960,
      "step": "2024 mean, face-to-face",
      "value": 25.5154
    },
    {
      "conf_high": 48.9016,
      "conf_low": 47.1532,
      "decomposition": "oth_education",
      "kind": "start",
      "n": 1718,
      "step": "1978 mean",
      "value": 48.0274
    },
    {
      "conf_high": -25.4296,
      "conf_low": -28.1773,
      "decomposition": "oth_education",
      "kind": "delta",
      "n": 6753,
      "step": "Within groups",
      "value": -26.8296
    },
    {
      "conf_high": 0.0295342,
      "conf_low": -0.904474,
      "decomposition": "oth_education",
      "kind": "delta",
      "n": 6753,
      "step": "Group mix",
      "value": -0.442385
    },
    {
      "conf_high": 0.618143,
      "conf_low": -0.796515,
      "decomposition": "oth_education",
      "kind": "delta",
      "n": 6753,
      "step": "Interaction",
      "value": -0.0722497
    },
    {
      "conf_high": 21.5136,
      "conf_low": 19.8527,
      "decomposition": "oth_education",
      "kind": "end",
      "n": 5035,
      "step": "2024 mean",
      "value": 20.6832
    },
    {
      "conf_high": 71.8374,
      "conf_low": 70.1858,
      "decomposition": "own_strength",
      "kind": "start",
      "n": 1723,
      "step": "1978 mean",
      "value": 71.0116
    },
    {
      "conf_high": -2.48989,
      "conf_low": -4.61243,
      "decomposition": "own_strength",
      "kind": "delta",
      "n": 6803,
      "step": "Within groups",
      "value": -3.56682
    },
    {
      "conf_high": 2.76289,
      "conf_low": 1.56799,
      "decomposition": "own_strength",
      "kind": "delta",
      "n": 6803,
      "step": "Group mix",
      "value": 2.16149
    },
    {
      "conf_high": 1.4235,
      "conf_low": 0.412235,
      "decomposition": "own_strength",
      "kind": "delta",
      "n": 6803,
      "step": "Interaction",
      "value": 0.915422
    },
    {
      "conf_high": 71.3448,
      "conf_low": 69.6986,
      "decomposition": "own_strength",
      "kind": "end",
      "n": 5080,
      "step": "2024 mean",
      "value": 70.5217
    }
  ],
  "id": "decomposition",
  "notes": [
    "The decomposition holds the 1978 mix of strong partisans, weak partisans and leaners fixed and lets each group's mean change, then adds the change in the mix and the term for both together, so the three steps add to the total. Intervals on the three steps come from redrawing the respondents of each year with replacement many times and taking the 95% interval of the redrawn estimates; the start and end bars use the Kish interval, so the totals differ slightly from the normal-curve intervals used elsewhere in the chapter.",
    "Groups: strong (party identification 1 or 7), weak (2 or 6) and leaner (3 or 5) on the seven-point scale. The education view uses three groups and leaves out respondents with no education answer, so its total fall is {fact:ss_edu_total_fall} against {fact:oth_fall} in the strength views."
  ],
  "source": "ANES Cumulative Data File, 1978 and 2024; partisans including leaners; weighted (VCF0009z; weight_ftf for the face-to-face view)",
  "spec": {
    "format": {
      "digits": 1
    },
    "kind": "kind",
    "step": "step",
    "value": "value",
    "valueLabel": "Mean rating of the other party (0 to 100)"
  },
  "subtitle": "Decomposition of the change in the mean rating between 1978 and 2024 over strength-of-attachment groups, partisans including leaners, points on the 0 to 100 thermometer",
  "title": "Change within groups accounts for {fact:ss_oth_within_fall} of the {fact:ss_oth_total_fall} points the other-party rating fell",
  "type": "waterfall",
  "views": [
    {
      "filter": {
        "decomposition": "oth_strength"
      },
      "id": "oth_strength",
      "label": "Other party"
    },
    {
      "caption": "The same decomposition with the 2024 end point restricted to the face-to-face sample (weight_ftf). The fall is smaller because the face-to-face sample rates the other party higher, and change within groups is again almost all of it.",
      "filter": {
        "decomposition": "oth_strength_ftf"
      },
      "id": "oth_strength_ftf",
      "label": "Face-to-face, 2024",
      "title": "Among 2024 face-to-face respondents, change within strength groups accounts for {fact:ss_ftf_within_fall} of the {fact:ss_ftf_total_fall} points the rating fell since 1978"
    },
    {
      "caption": "The same decomposition over three education groups (high school or less, some college, college degree or more). The rising share of college graduates accounts for little of the fall.",
      "filter": {
        "decomposition": "oth_education"
      },
      "id": "oth_education",
      "label": "Education groups",
      "title": "Change within education groups accounts for {fact:ss_edu_within_fall} of the {fact:ss_edu_total_fall} points the rating fell, and the shift in education mix for {fact:ss_edu_comp_fall}"
    },
    {
      "caption": "The decomposition applied to the rating of the own party. The mean own-party rating fell inside the weak group (from {fact:weak_own_1978} to {fact:weak_own_2024}) and the leaning group (from {fact:leaner_own_1978} to {fact:leaner_own_2024}), and the larger share of strong partisans, who rate their own party higher, raised the overall mean.",
      "filter": {
        "decomposition": "own_strength"
      },
      "id": "own_strength",
      "label": "Own party",
      "spec": {
        "valueLabel": "Mean rating of the own party (0 to 100)"
      },
      "title": "The own-party rating changed by {fact:ss_own_total} because falls within strength groups ({fact:ss_own_within}) were offset by the growth of strong partisans ({fact:ss_own_comp})"
    }
  ],
  "width": "body"
}