Learning curves: analysing pace and challenge in four successful puzzle games

The pace at which challenges are introduced in a game has long been identified as a key determinant of both the enjoyment and difficulty experienced by game players, and their ability to learn from game play. In order to understand how to best pace challenges in games, there is great value in analysing games already demonstrated as highly engaging. Play-through videos of four puzzle games (Portal, Portal 2 Co-operative mode, Braid and Lemmings), were observed and analysed using metrics derived from a behavioural psychology understanding of how people solve problems. Findings suggest that; 1) the main skills learned in each game are introduced separately, 2) through simple puzzles that require only basic performance of that skill, 3) the player has the opportunity to practice and integrate that skill with previously learned skills, and 4) puzzles increase in complexity until the next new skill is introduced. These data provide practical guidance for designers, support contemporary thinking on the design of learning structures in games, and suggest future directions for empirical research

Dynamically adaptive educational games: A new perspective

Sajjadi P, Van Broeckhoven F, De Troyer O. Dynamically adaptive educational games: A new perspective. In: International Conference on Serious Games. 2014: 71--76

Two-dimensional echocardiographic evaluation of left ventricular ejection fraction by the ellipsoid single-plane algorithm: a reliable method for assessing low or very low ejection fraction values?

The reliability of two-dimensional (2D) echocardiographic estimation of left ventricular ejection fraction (EF) is commonly recognized, but no satisfactory data are available about the accuracy of low or very low EF values determined by 2D echocardiography (ECHO-EF). The purpose of our study was to assess the reliability of low ECHO-EF values obtained using a simple time-economical algorithm such as the ellipsoid single-plane area-length method. Radionuclide angiography (RAD-EF) was taken as the standard of comparison. We studied 59 consecutive patients (31 women and 28 men) referred to our echocardiographic laboratory. Both 2D echocardiography and radionuclide angiography were blindly performed within 48 h of one another. EF was calculated by the two methods and then compared. Data were globally analyzed. Furthermore, data were divided and analyzed according to the ECHO-EF cut-off point of 50%. An ECHO-EF value of 50% was chosen to conventionally distinguish between low ECHO-EF values and normal-high ones. Data were plotted, and the line of equality and the regression lines were drawn. Regression line slopes, correlation coefficients, means and standard deviations were calculated. The agreement was analyzed by calculating the mean difference (RAD-EF-ECHO-EF) and the standard deviation of the differences. ECHO-EF was linearly related to RAD-EF even when data were split. In particular, as regards ECHO-EF < or = 50%, the regression line practically overlapped the line of equality, and the two methods showed both a strong correlation and a good degree of agreement