Computational complexityIn computer science, the computational complexity or simply complexity of an algorithm is the amount of resources required to run it. Particular focus is given to computation time (generally measured by the number of needed elementary operations) and memory storage requirements. The complexity of a problem is the complexity of the best algorithms that allow solving the problem. The study of the complexity of explicitly given algorithms is called analysis of algorithms, while the study of the complexity of problems is called computational complexity theory.
EstimatorIn statistics, an estimator is a rule for calculating an estimate of a given quantity based on observed data: thus the rule (the estimator), the quantity of interest (the estimand) and its result (the estimate) are distinguished. For example, the sample mean is a commonly used estimator of the population mean. There are point and interval estimators. The point estimators yield single-valued results. This is in contrast to an interval estimator, where the result would be a range of plausible values.
Training and developmentTraining and development involve improving the effectiveness of organizations and the individuals and teams within them. Training may be viewed as related to immediate changes in organizational effectiveness via organized instruction, while development is related to the progress of longer-term organizational and employee goals. While training and development technically have differing definitions, the two are oftentimes used interchangeably and/or together.
Performance improvementPerformance improvement is measuring the output of a particular business process or procedure, then modifying the process or procedure to increase the output, increase efficiency, or increase the effectiveness of the process or procedure. Performance improvement can be applied to either individual performance, such as an athlete, or organisational performance, such as a racing team or a commercial business. The United States Coast Guard has published the Performance Improvement Guide (PIG), which describes various processes and tools for performance management at the individual and organisational levels.
Ball-and-stick modelIn chemistry, the ball-and-stick model is a molecular model of a chemical substance which displays both the three-dimensional position of the atoms and the bonds between them. The atoms are typically represented by spheres, connected by rods which represent the bonds. Double and triple bonds are usually represented by two or three curved rods, respectively, or alternately by correctly positioned sticks for the sigma and pi bonds.
