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[L. probabilitas, likelihood]

1. Likelihood.
2. The ratio that expresses the possibility of the occurrence of a specific event. The probability of a tossed coin landing heads or tails is one half or 50% each. This 50% probability remains the same every time a coin is tossed. Probability ratios based on sophisticated techniques are used for estimating the chance of occurrence of diseases in a population and in projecting vital statistics such as birth and death rates.

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