Konfidentsusintervallide

Konfidentsusintervallide is a statistical concept used to estimate a population parameter, such as the mean or proportion, from sample data. Instead of providing a single point estimate, a confidence interval provides a range of values that is likely to contain the true population parameter. The level of confidence, usually expressed as a percentage (e.g., 95%), indicates how often the method used to construct the interval will capture the true parameter if the sampling process were repeated many times.

A confidence interval is calculated by taking a sample statistic (e.g., sample mean) and adding and subtracting a margin of error. The margin of error depends on the confidence level desired and the variability of the data, often measured by the standard error. A higher confidence level or greater variability will result in a wider interval. Conversely, a lower confidence level or less variability will lead to a narrower interval.

Confidence intervals are crucial in statistical inference as they quantify the uncertainty associated with estimating population characteristics from samples. They allow researchers to draw conclusions about a population with a specified degree of certainty. For example, a 95% confidence interval for the average height of a population might be 170 cm to 175 cm. This means that we are 95% confident that the true average height of the population falls within this range. It's important to remember that a confidence interval does not state the probability that the true population parameter falls within a *specific* interval; rather, it refers to the long-run success rate of the interval construction method.