Normal distribution Essays

Normal Distribution Part 1 The article by Atkinson and Geiser (2015) titled “The Big Problem with the New SAT” that was published on 4th May 2015 in the New York Times indicates that the normal distribution curve is used to rank students based on their SAT scores. In particular, the authors assert that the College Board designs the SAT exams with an intent to achieve the “bell-shaped” curve that shows a majority of the most students’ scores in the middle and less students at the higher and lower

Contextual outlier: during a normal week, Joe usually charges around $100 to his credit card. During the week leading up to Christmas, Joe charges over $1000 to his credit card. Out of context, this may look like fraud but because we know people’s spending habits around the holidays it probably isn’t an outlier. b. Collective outlier: Let’s say Dr. Velkoski teaches three night classes here at DePaul each week. Each class has 25 students enrolled. If we take a look at the distribution of attendance and students

standard normal curve between z = 0 and z = 1.65. Answer: The value 1.65 may be written as 1.6 to .05, and by locating 1.6 under the column labeled z in the standard normal distribution table (Appendix 2) and then moving to the right of 1.6 until you come under the .05 column, you find the area .450 . This area is expressed as 2. Find the area under the standard normal curve between z = -1.65 and z = 0. Answer: The area may be represented as . Since the normal curve

considered normal, between +12 μm and +15μm are suspicious, and more than +15 μm are typically indicative of keratoconus. Similar numbers about 5 μm higher apply to posterior elevation maps. 2. Anterior curvature map (Tomidokoro et al., 2000): The steepening of the cornea, irregular astigmatism, inferior steepening (I-S difference), location of steepest point and the thinnest point on the cornea may help in the diagnosis of keratoconus. 3. Pachymetry and thickness distribution maps (Ambro´sio

Chapter two reviews probability and the normal distribution. Probability equals the number of events meeting the specified condition divided by the number of possibilities (Mirabella, p. 2-1, 2011). For example, my organization two primary products. Those products are orange postal bags and brown boxes. Forty percent of the volume consists of orange postal bags. A simple probability question could be as follows; out of ten packages, how many postal bags are processed. The answer would be four out

Bottling Company Case Study As a manager at a major bottling company, customers have complained that the bottles of the brand of soda produced in the company contain less than the advertised sixteen (16) ounces of product. There is need to solve the problem at hand and has to be investigated. Employees are instructed to pull thirty (30) bottles off the line at random from all the shifts at the bottling plant and measure the amount of soda there is in each bottle. The table (i) below shows the number

analysis in economics, event history analysis in sociology and medical researchers give it the name of survival analysis. Survival analysis is used because the survival data are generally not symmetrically distributed, so it can not follow the normal distribution. The survival data depend on the time and it render standard methods in which the survival times are frequently censored [1]. Censored data arises when the study end and the patient still alive, a patient is lost to follow-up during the study

Analysis of Variance (ANOVA) is a statistical method used to test differences between two or more means. Though it is called "Analysis of Variance" but actually it is "Analysis of Means." ANOVA was developed by Ronald Fisher in 1918 and is the extension of the t and the z test. Before the use of ANOVA, the t-test and z-test were commonly used. But the problem with the T-test is that it cannot be applied for more than two groups. This test is also called the Fisher analysis of variance, which

that the standard error of the mean is the standard deviation of a sampling distribution of means. I understand how to calculate the SEM (simply divide the standard deviation of the sample by the square root of the sample size minus one). I understand that SEM is not the same as standard deviation. I also recognize that if the sample size is increased, the standard error of the

Lab Report 1 Logarithmic Plotting Devin Edwards ENGR 3070L CRN: 27194 January 17, 2018 Dr. Margraves Objective The purpose of this experiment is to graph and look at the logarithmic plots and write corresponding exponential equations that match the “Best Fit” line of the data points. Theory The data in Table 1 can be represented by the exponential equation given in equation 1 below. Equation 1 is also used for Cartesian plots: Q=KH^n (1) On this type of plot a straight line

the dynamical system into a regular stationary process produces such a sequence, then the dynamical system is called a Bernoulli system. 1.6.1 Deterministic Chaos Small differences in initial conditions (such as those due to rounding errors in numerical computation) yield widely diverging outcomes for chaotic systems, rendering long-term prediction impossible in general. This happens even though these systems are deterministic, meaning that their future behavior is fully determined by their initial

Definition, Characteristics, and Etiology or Causes It is only in the 1960’s that the term ‘learning disabilities’ were used to refer to severe learning problems of individuals in order to provide administrative convenience and focus of advocacy. Although findings related to learning disabilities date back in the 1800s, Learning Disabilities is still a new area of Special Education and there is no single agreed upon definition of it yet. One influential definition that is accepted by most educators

Incorporating Continuous Assessment with Exams Examinations have been the gold standard for measuring the performance of students at the university level in the educational system. However, it may be possible that continuous assessment is more accurate for measuring overall student performance due to the fact that students are given different types of tasks to assess their knowledge, such as homework, papers, and quizzes. Exams have many pros and cons, but measuring a student’s performance solely

data that are collected at lower levels of measurement (nominal and ordinal scales). They have lower efficiency and do not require homogeneity of variance as well as normally distributed population. In short, nonparametric statistical tests are distribution-free statistical procedures and are less powerful. Also, they do not require the stringent conditions for parametric tests. Examples of nonparametric tests include Mann-Whitney, Wilcoxon test, Kruskal-Wallis test, sign test, median test, rank order

Developing models based on the population data are called population modeling (pop modeling), where sparse sampling would be sufficient to obtain required data for modeling. Using population PK models, population kinetics parameters (volume of distribution (V), clearance (CL) etc.) and variability, as well as individual PK parameters can be obtained. Inter individual variability can be tested by adding them to the model as ‘covariates’. To assess drug effect such as adverse effect, biomarkers, change

x = 10 while x != 0: print x x = x - 1 print " we 've counted x down, and it now equals", x print "And the loop has now ended." Boolean Expressions So, above, where we talked through w to write a “while” loop, you see where we put “condition that the loop continues”? What goes in here is what we call a Bool- ean expression. All that means is a question that can be answered with a TRUE or a FALSE re- sponse. Let’s say that you wanted to put that your age is the same as that of the person

Introduction For two days, on the 14th and 15th of April, a field excursion to Hastings Point, New South Wales was conducted. At Hastings Point, topography, abiotic factors and organism distribution were measured and recorded, with the aim of drawing links between the abiotic factors of two ecosystems (rocky shore and sand dunes), the organisms which live in them, and the adaptations they have developed to cope with these conditions. Within these two ecosystems, multiple zones were identified and

The Stroop Effect is a test that tests the mental state of the person. For this experiment, I will test the reaction time between the test when the color and word are the same (Matching) and when the color and word are different (Mis-Matching). Next, you see the differences in the reaction times and average up all the times. After, you do that step three times, see the difference between the 1st try and the 3rd try. How is reaction time ( which is how fast you can do something) related to the Stroop

determine each pixel belongs to background or foreground.Wis the weights between the pattern and summationneurons, which are used to point out with which a pattern belongs to the background or foreground. They areupdated when each new value of a pixel at a certain position received by implementing the following function:Wt+1ib=fc(1−βNpn)Wib+MAtβ!(37)Wt+1i f=(1−Wt+1ib)(38)whereWtibis the weight between theith pattern neuron and the background summation neuron at timet,βisthe learning rate,Npnis the

In Plato’s Republic, Socrates and his peers attempt to define justice. Unlike the definitions that his peers give, Socrates is searching to define justice as a structure, not a set of behaviors. Socrates uses a tripartite city-soul analogy to define justice and show that it is found when there is harmony between the three parts of the city—guardians, auxiliaries, producers—mirrored to the three parts of the soul—reason, spirit, appetite. Although Socrates provides a well-structured account of justice