Statistical analysis is needed because data always have some degree of uncertainty; a value that we determine from a single measurement, or even set of measurements, is not necessarily going to tell us exactly what value we will determine with additional measurements. Statistical analysis uses the mathematics of probability to create tools that we can use to deal with … [Read more...]

## Statistics Corner: Weibull Distribution

A little over a pandemic ago, the first article in this series on statistical analysis mentioned that a fundamental aspect of statistics is that one assumes a mathematical model that describes the distribution of a data set and then uses that model to estimate the probability that a given value or set of values will occur [1]. This allows us, for example, to estimate whether … [Read more...]

## Statistic Corner: Comparing Populations

Introduction Previous articles in this series described the normal distribution and how it is used to relate probability and confidence levels [1, 2]. A practical application of the use of the confidence interval was to describe how to determine the range of values in which the true mean of a population falls within, based on the mean and standard deviation calculated from a … [Read more...]

## Calculation Corner: Advective Thermal Resistance

A previous Electronics Cooling article, which discussed the process for analyzing the thermal performance of cooling fans [1], mentioned the need of accounting for the increasing coolant temperature as air passes through a heat sink. That article used an ‘average’ air temperature, which was defined as the midpoint between the inlet and outlet air temperatures. This article … [Read more...]

## Normal Distribution

Introduction The previous column in this series [1] discussed statistical probability and showed that the plot of the probability of a given value occurring within a population can look like a hill in which there is a peak in the middle that tapers off to increasingly smaller slopes on each side. The example in that column referred to the scores produced by shaking a number of … [Read more...]