Tõendusvahemik

Tõendusvahemik, also known as a confidence interval, is a statistical concept used to express the uncertainty associated with a sample statistic. It provides a range of values within which the true population parameter is likely to lie, with a certain level of confidence. For example, a 95% tõendusvahemik means that if we were to repeat the sampling process many times, 95% of the calculated tõendusvahemikud would contain the true population parameter.

The width of a tõendusvahemik is influenced by several factors, including the sample size, the variability of the data, and the desired confidence level. A larger sample size generally leads to a narrower tõendusvahemik, indicating a more precise estimate. Similarly, lower variability in the data also results in a narrower interval. A higher confidence level, such as 99% compared to 95%, requires a wider interval to achieve that greater certainty.

Tõendusvahemikud are widely used in various fields, including scientific research, market analysis, and opinion polling. They allow researchers to quantify the precision of their estimates and to make more informed conclusions about the population based on sample data. It is important to remember that a tõendusvahemik does not guarantee that the true parameter falls within the interval; rather, it expresses the long-run probability of the method capturing the true value.