How do you determine reliability of a measurement

For example, you might determine the amount of dissolved iron in a solution by adding a reagent that reacts with the iron to give a red color, which you measure by observing the intensity of green light that passes through a fixed thickness of the solution.If all the researchers give similar ratings, the test has high interrater reliability.Determines how comparable are two different versions of the same measure.correlate the test scores of the two tests.For example, intelligence is generally thought to be consistent across time.Mtbf is a basic measure of an asset's reliability.A measure of the accuracy of a test or measuring instrument obtained by measuring the same individuals twice and computing the correlation of the two sets of measures.

As we strive to determine actual quantities with our measuring devices, the measurements we record will sometime be too high, sometimes be too low, and sometimes be right on.Taking the example of the ahu above, the calculation to determine mtbf is:The correlation coefficient for these data is +.95.Measuring a variable (anything that can take on different values) involves assigning quantitative numbers to observations about the world.