Flame Emission Spectroscopy (FES) is a powerful analytical technique widely used for identifying and quantifying elements in various samples. In this laboratory experiment, undergraduate students were introduced to FES and its significance in analytical chemistry. The experiment aimed to provide students with hands-on experience in constructing…

This inquiry is focused on three indicators of the precision of measurement--conditional on fixed values of ?, the latent variable of item response theory (IRT). The indicators that are compared are (1) The traditional, conditional standard errors, s(eX|?) = CSEM; (2) the IRT-based conditional standard errors, s[subscript irt](eX|?)=C[subscript…

In this work, we have developed an alternative device composed by an Arduino board and an INA219 sensor to experimentally obtain the mathematical formulas describing the charge and discharge of the capacitor for educational proposes. We have obtained excellent agreement between theoretical prediction and experimental measurements. The INA219 DC…

This work proposes simple experiments to introduce some fundamental concepts of the measurement area. It associates theory and practice through a strategy where the students create a real temperature data set with an Arduino board and three LM35DZ sensors and later use mathematical software to identify theoretical concepts as measurement accuracy…

Although the root-mean squared deviation (RMSD) is a popular statistical measure for evaluating country-specific item-level misfit (i.e., differential item functioning [DIF]) in international large-scale assessment, this paper shows that its sensitivity to detect misfit may depend strongly on the proficiency distribution of the considered…

A low-cost and simple setup to measure the densities of liquids is introduced herein. The results and reliability of this setup were evaluated for pure liquids, water-ethanol binary mixtures, and aqueous NaCl solutions. The constructed densitometer provided density values with acceptable relative errors (less than ±3.0%), which were compared to…

All students, from college freshmen to advanced graduate students, have asked themselves, "Will this decision make me happy?" The vast majority of them have been wrong. Affective forecasting, the process of predicting future feelings, is a topic of great interest to students due to its applicable and highly relatable nature. This article…

Precision is a key facet of test development, with score reliability determined primarily according to the types of error one wants to approximate and demonstrate. This article identifies and discusses several primary forms of reliability estimation: internal consistency (i.e., split-half, KR-20, a), test-retest, alternate forms, interscorer, and…

When conducting experiments involving the measurement of physically related quantities, choosing an appropriate spacing for the experimental independent variable is a crucial procedure whose consequences may go beyond data graphical visualization. This is particularly true if the measured quantities are nonlinearly related and experimental errors…

Identifying English language learners (ELLs) with learning disabilities has become very important in education settings so that appropriate educational services can be provided to this group of students. Linguistic diversity may increase the measurement error and reduce the reliability of assessments. This article discusses the issues with…

State testing programs today are more extensive than ever, and their results are required to serve more purposes and high-stakes decisions than one might have imagined. Assessment results are used to hold schools, districts, and states accountable for student performance and to help guide a multitude of important decisions. This report describes…

"Scaling" is the process of constructing a score scale that associates numbers or other ordered indicators with the performance of examinees. Scaling typically is conducted to aid users in interpreting test results. This module describes different types of raw scores and scale scores, illustrates how to incorporate various sources of…