Summary Essay Example | Topics and Well Written Essays - 250 words - 64

Summary - Essay Example The impact of the violation of the local independence assumption on both reliability and information function was also evident where the study results showed that if the items were treated as a locally independent (which is in fact in violation of the items local independence), the reliability coefficient would then be biased to the top as well as the information for the test function. According to (Chen & Wang, 2007) they used index Q3 in the study to detect the items which including violation of local independence assumption. Then through simulation data according to the three parameter model , the results indicate that if it appeared that a violation of the local independence assumption between the items were corrected, then they were locally independent. This affects the estimated parameter discrimination where if the violation is positive, then to answer the first item correct increases the probability of the correct answer on the other item. The discrimination parameter estimate will then be biased upwards while at the same time, if the violation of local independence between items will be negative, then the discrimination parameter estimate will be biased to the downwards. Chen and Thissen (Chen & Thissen, 1997) used Q3,, to examine the local independence of items and a test was generated. As the results indicate, there are two types of local dependence between the items. First one is known as (ULD) Underlying Local Dependence and this type of local dependence is shown by the items there. There are some separate traits for items groups showing local dependence, but not for all the test items. This means that there is another traits which is not the general trait measured by the test. The second type of local dependence is known as (SLD) Surface Local Dependence, and this type of local dependence of items is shown in the

Six Sigma Research Paper Example | Topics and Well Written Essays - 1500 words

Six Sigma - Research Paper Example I selected this topic so as to be better equipped with the knowledge and skills that can enable me improve the overall performance of a company I hope to work for in future; Caterpillar Incorporated. Six Sigma is a concept that has been utilized by large and highly profitable organizations to aid their businesses to perform better than before. In fact, it has been deemed as an entirely new method that works, in managing businesses according to Pyzdek (26). Six Sigma will be important to me since, compared to other techniques of quality improvement; it scores much higher and allows organizations to realize their full potentials. For instance, the Total Quality Management (TQM) technique mostly focuses on attaining predetermined quality levels but does not push the business to perform at its peak. As future industry leader who will seek to get the most from his business, I will definitely find this concept to be of the uttermost importance since it has worked for other big companies and will definitely work for me too. Six Sigma focuses on making consistent quality improvements until the organization is fully optimized. On achieving a certain quality level, the technique calls for the business to shift gears and begin concentrating on attaining better quality levels. This whole process continues to the optimization off all the business processes. Six Sigma is therefore important for any company as it will push it to efficiently produce higher quality products. This will be advantageous to me as, apart from improving the company’s overall efficiency and reducing operational costs, it will in addition give me a lead over my competitors. DMADV and DMAIC are the acronyms of the two methodologies that Sigma Six projects follow in eliminating defects from products or processes. The methodologies are both made up of five phases. Define-Measure-Analyze-Implement-Control or in short, DMAIC, is used in