https://www.ae911truth.org/evidence/the-official-theory-twin-towers 'The Official Theory | Twin Towers The seven-year quest to produce an official technical explanation for the destruction of World Trade Center Buildings 1, 2, and 7 represents an unparalleled case study in “expectation bias." NFPA 921: Guide for Fire and Explosion Investigations, which serves as the national guide for fire and explosion investigations in the United States, defines “expectation bias” as follows: “Expectation bias is a well-established phenomenon that occurs in scientific analysis when investigator(s) reach a premature conclusion without having examined or considered all of the relevant data. Instead of collecting and examining all of the data in a logical and unbiased manner to reach a scientifically reliable conclusion, the investigator(s) uses the premature determination to dictate investigative processes, analyses, and, ultimately, conclusions, in a way that is not scientifically valid. The introduction of expectation bias into the investigation results in the use of only that data that supports this previously formed conclusion and often results in the misinterpretation and/or the discarding of data that does not support the original opinion. Investigators are strongly cautioned to avoid expectation bias through proper use of the scientific method.” NFPA 921 also explicitly urges investigators to avoid presumption in the formulation of hypotheses: “Until data have been collected, no specific hypothesis can be reasonably formed or tested. All investigations of fire and explosion incidents should be approached by the investigator without presumption…until the use of scientific method has yielded testable hypotheses, which cannot be disproved by rigorous testing.” As discussed below, the two official investigations of the WTC destruction flagrantly violated these principles, resulting in incomplete hypotheses that are wholly unsupported by any evidence and that ignore most...