{
  "id": "programming.variables.uninitialized-is-zero",
  "uri": "https://open-misconceptions.github.io/miscon-data/m/programming.variables.uninitialized-is-zero",
  "uuid": "436c64f5-62ac-40c8-86f7-60b05c57c1de",
  "version": "0.1.1",
  "status": "draft",
  "trust": "low",
  "title": "Uninitialised variables start at zero",
  "statement": "A variable that has been declared but never assigned holds zero, or an empty value, so it can be safely read or added to.",
  "kind": "overgeneralization",
  "domain": "programming.variables",
  "about": [
    {
      "scheme": "Miscon",
      "uri": "https://open-misconceptions.github.io/miscon-data/c/programming.variables.initialization"
    }
  ],
  "level_band": [
    "secondary",
    "undergraduate"
  ],
  "locale": "en",
  "evidence_patterns": [
    {
      "item_shape": "predict the outcome of reading a declared but unassigned local variable",
      "signature": "predicts 0 or empty output rather than a compile error or garbage value",
      "example": {
        "item": "int count;\ncount = count + 1;\nSystem.out.println(count);",
        "expected": "Compile error: count might not have been initialized",
        "response": "1"
      }
    }
  ],
  "discriminators": {
    "vs_slip": "A slip is forgetting one initialisation while knowing it is needed. The belief is stated ('it starts at zero') and the learner omits initialisation habitually."
  },
  "relations": {
    "conflicts_with": [
      {
        "external": "https://open-misconceptions.github.io/miscon-data/c/programming.variables.initialization",
        "label": "A variable has no usable value until it is assigned"
      }
    ],
    "resolved_by": [
      {
        "external": "https://open-misconceptions.github.io/miscon-data/c/programming.variables.initialization",
        "label": "A variable has no usable value until it is assigned"
      }
    ]
  },
  "alignments": [
    {
      "scheme": "progmiscon",
      "code": "Java/LocalVariablesAutoInitialized",
      "uri": "https://progmiscon.org/misconceptions/Java/LocalVariablesAutoInitialized",
      "relation": "close-match"
    }
  ],
  "provenance": {
    "sources": [
      {
        "type": "inventory",
        "citation": "Chiodini, L., Moreno Santos, I., Gallidabino, A., Tafliovich, A., Santos, A. L., & Hauswirth, M. (2021). A curated inventory of programming language misconceptions. In Proceedings of the 26th ACM Conference on Innovation and Technology in Computer Science Education (ITiCSE '21), 380-386.",
        "doi": "10.1145/3430665.3456343",
        "url": "https://progmiscon.org/",
        "note": "Inventory consulted for the misconception name and scope only; progmiscon publishes no licence for its text, so Open Misconceptions' statements and examples are written independently."
      },
      {
        "type": "paper",
        "citation": "Kaczmarczyk, L. C., Petrick, E. R., East, J. P., & Herman, G. L. (2010). Identifying student misconceptions of programming. In Proceedings of the 41st ACM Technical Symposium on Computer Science Education (SIGCSE '10), 107-111.",
        "doi": "10.1145/1734263.1734299",
        "note": "Memory-model misconceptions including uninitialised storage."
      },
      {
        "type": "paper",
        "citation": "Qian, Y., & Lehman, J. (2017). Students' misconceptions and other difficulties in introductory programming: A literature review. ACM Transactions on Computing Education, 18(1), Article 1.",
        "doi": "10.1145/3077618"
      }
    ],
    "origin": "llm-drafted",
    "notes": "Drafted from the cited literature for the Open Misconceptions seed pack; statement, examples and discriminators are original text. Awaiting maintainer review."
  },
  "history": {
    "changelog": [
      {
        "version": "0.1.1",
        "date": "2026-09-05",
        "change": "Schema 0.2 migration: about/alignments carry a free-string scheme (corestandards.org URLs relabelled CCSS where present); trust computed from reviews[] (none yet, so low); no change to the statement or evidence."
      }
    ]
  },
  "license": "CC-BY-4.0"
}