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  2. False positives and false negatives - Wikipedia

    en.wikipedia.org/wiki/False_positives_and_false...

    In statistical hypothesis testing, the analogous concepts are known as type I and type II errors, where a positive result corresponds to rejecting the null hypothesis, and a negative result corresponds to not rejecting the null hypothesis. The terms are often used interchangeably, but there are differences in detail and interpretation due to ...

  3. Laboratory quality control - Wikipedia

    en.wikipedia.org/wiki/Laboratory_quality_control

    Laboratory quality control is designed to detect, reduce, and correct deficiencies in a laboratory's internal analytical process prior to the release of patient results, in order to improve the quality of the results reported by the laboratory. Quality control (QC) is a measure of precision, or how well the measurement system reproduces the ...

  4. Type I and type II errors - Wikipedia

    en.wikipedia.org/wiki/Type_I_and_type_II_errors

    Type I and type II errors. In statistical hypothesis testing, a type I error, or a false positive, is the rejection of the null hypothesis when it is actually true. For example, an innocent person may be convicted. A type II error, or a false negative, is the failure to reject a null hypothesis that is actually false.

  5. Observational error - Wikipedia

    en.wikipedia.org/wiki/Observational_error

    When either randomness or uncertainty modeled by probability theory is attributed to such errors, they are "errors" in the sense in which that term is used in statistics; see errors and residuals in statistics.

  6. pH indicator - Wikipedia

    en.wikipedia.org/wiki/PH_indicator

    A pH indicator is a halochromic chemical compound added in small amounts to a solution so the pH ( acidity or basicity) of the solution can be determined visually or spectroscopically by changes in absorption and/or emission properties. [ 1] Hence, a pH indicator is a chemical detector for hydronium ions (H 3 O +) or hydrogen ions (H +) in the ...

  7. Analytical chemistry - Wikipedia

    en.wikipedia.org/wiki/Analytical_chemistry

    Analytical chemistry studies and uses instruments and methods to separate, identify, and quantify matter. [ 1] In practice, separation, identification or quantification may constitute the entire analysis or be combined with another method. Separation isolates analytes.

  8. Basis set superposition error - Wikipedia

    en.wikipedia.org/wiki/Basis_set_superposition_error

    Other than using infinite basis sets, two methods exist to eliminate the BSSE. In the chemical Hamiltonian approach (CHA), [ 4 ] [ 5 ] basis set mixing is prevented a priori , by replacing the conventional Hamiltonian with one in which all the projector -containing terms that would allow mixing have been removed.

  9. Trial and error - Wikipedia

    en.wikipedia.org/wiki/Trial_and_error

    This approach can be seen as one of the two basic approaches to problem-solving, contrasted with an approach using insight and theory. However, there are intermediate methods which for example, use theory to guide the method, an approach known as guided empiricism .