Abstract- The Latin Square Design is one of the most important designs used in many experimentation. It provides more opportunity than Complete Randomized Design and Randomized Complete Block Design for the reduction of experimental error by skillful planning. In our seminar, we talked about some of experimental designs including Complete Randomized Design (CRD), Randomized Complete Block Design (RCBD) and Latin Square Design (LSD). We design an experiment to study the effect of different "Calculus II" lecture time on the student's marks in the first exam. We choose the marks from different classes of "Calculus II", we analyze the marks of students using SPSS program. In our work, we dwelled into the computation aspect and focused on interpretation of the results since it is much more important than the drudgery of complex computations. We used the statistical program (SPSS) for analyzing the results of our experiment. We conclude that the lecture time does not affect on the marks of students when we apply the CRD. When we use RCBD, the results were recorded and we conclude that the lecture time affect on their marks in the first exam of "Calculus II" .
I. INTRODUCTION
Before an experiment is performed, we must address a design. In order to understand well the structure of this design and it is application, we have to discuss firstly the basic concepts of any experimental design as we will discuss in chapter one. In our seminar, we will discuss some of the common experimental designs which are the CRD and RCBD in chapter two. We will describe each of these two designs in details, the structure of these designs, the model, analysis of variance and the assumptions embodied in the model. In chapter three, we will take the case when we have two nuisance factors that we wish to control them by blocking them off in two directions in order to study the effect of a treatment variable. The design for accomplishing this is called a Latin Square Design. We introduce the description of this design and analysis of variance of the design.
II. DESIGN OF EXPERIMENTS
Much of our knowledge about products and processes in the engineering and scientific
Disciplines are derived from experimentation. An experiment is a series of tests conducted in a systematic
manner to increase the understanding of an existing process or to explore a new product or process. Design of Experiments, is a tool to develop an experimentation strategy that maximizes learning using a minimum of resources. Design of Experiments is widely used in many fields with broad application across all the natural and social sciences. It is extensively used by engineers and scientists involved in the improvement of manufacturing processes to maximize yield and decrease variability. Often times, engineers also work on products or processes where no scientific theory or principles are directly applicable. Experimental design techniques become extremely important in such situations to develop new products and processes in a cost-effective and confident manner.
If an experiment has been properly designed or planed, the data will have been collected in the most efficient manner for the problem being considered, and as a result the analysis of an experiment will lead to valid statistical inferences. The purpose of this chapter is to –firstly- define the experimental design concept, and other related concepts in the terminology of the design of experiment. Then, we shall introduce some basic principles of experimental design.
In order to realize the meaning of the experimental design, we need to show firstly the definition of an experiment. An experiment is a process or study that results in the collection of data. The results of experiments are not known in advance. Usually, statistical experiments are conducted in situations in which researchers can manipulate the conditions of the experiment and can control the factors that are irrelevant to the research objectives.
There are some statistical concepts that must be clarified in this context:
Latin Square Design(LSD)
Rateebah Al Tamimi College of Applied Science Palestine Polytechnic University Hebron, Palestine aimman33@hotmail.com
Hanan Abdel Fatah College of Applied Science Palestine Polytechnic University Hebron, Palestine
Rabeeha Al Rajabi College of Applied Science Palestine Polytechnic University Hebron, Palestine
Khawla Almuhtaseb College of Applied Science Palestine Polytechnic University Hebron, Palestine