...STAT 572 Survival Analysis HW7 Problem: Data set: WHAS, Covariates: AGE, SEX, MITYPE. Perform survival regression. 1. Data Description. In this case, there is one continuous variable (AGE), and two categorical variables (SEX, MITYPE). We are studying how these three predicators affect patients’ survival time. For SEX, Male=0 and Female=1. For MI Type of patients, there are three values: 1 | Q-Wave | ST segment elevation myocardial infarction (STEMI) | 2 | Not Q-Wave | non-ST segment elevation myocardial infarction (NSTEMI) | 3 | Indeterminate | | Table 1.1 MI type explanation 2. Variable Analysis Since AGE is a continuous variable, to be convenience, we make it as categorical variable CAGE using 25%, 50% and 75% quantile at FSTAT=1. Using PROC UNIVARIATE to decide the cut point as follows: Variables | 25% Quantile | 50% Quantile | 75% Quantile | AGE | 64 | 72 | 80 | Table 2.1 Quantiles Cut Point for AGE Thus, all the variables are categorical, such that we can use the LIFETEST to test if different levels of covariates have the same effect on the survival curve. We are doing hypothesis testing for each predictor: H0:SSEX=0=SSEX=1 vs. H1:Not H0 H0:SMI=1=SMI=2=S(MI=2) vs. H1:Not H0 H0:SCAGE=0=SCAGE=1=SCAGE=2=S(CAGE=3) vs. H1:Not H0 First, we will test the equality over SEX, and compare the KM curve using LIFETEST and PHREG. Test | Chi-Square | DF | Pr > Chi-Square | Log-Rank...
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...Chapter 3: Introduction to Reliability Theory Claver Diallo OUTLINE 1. Part 1: Basic Reliability Models 1. 2. 3. 1. 2. 3. 4. 5. System Reliability function Probability distributions Reliability Block Diagram Serial and Parallel Structures Stand-by Structure k-out-of n Structure Complex structure 2. Part 2: Reliability of Structures 3. Part 3: Reliability Allocation 4. References 2 2 2 2 2 2 2 2 Chapter 3 - Part 1: Basic Reliability Models SYSTEM System: a collection of components or items performing a specific function. 4 4 4 4 4 4 4 4 STATE OF A SYSTEM A system is considered to be in one of the two following states: In operation (Up) Failed (Down) Transition from one state to the other occurs according to a known or unknown probability function. de aF de aF delllliiiiaF de aF 5 5 5 5 5 5 5 5 noitca ecnanetniaM noitca ecnanetniaM noitca ecnanetniaM noitca ecnanetniaM riapeR riapeR riapeR riapeR e eruliaF gn arepO gn arepO gniiiittttarepO gn arepO SYSTEM LIFETIME Lifetime is a measure of performance. Lifetime is a measure of performance. In general, lifetime is measured by the number In general, lifetime is measured by the of hours the system was in operation. number of hours the system was in operation. It can also be measured by the number of It can also be measured by the number of km or miles raced, number of pages copied, pages copied, km or miles raced, number wheel rotations, …etc. of wheel rotations, …etc. Lifetime (T) is a...
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...Preface In our data analysis we do some univariate analysis before proceeding to models. In survival analysis it is highly recommended to look at the Kaplan-Meier curves for all the categorical predictors. This will provide insight into the shape of the survival function for each group and give an idea of whether or not the groups are proportional. We also consider the tests of equality across strata to explore whether or not to include the predictor in the final model. For the categorical variables such as marital, eservice, plusservice and totalservice we use the log-rank test of equality across strata which is a non-parametric test. For the continuous variables such as age, address, income, education, employment, and reside we use a univariate Cox proportional hazard regression which is a semi-parametric model. Univariate analysis We consider the Chi-squared test for age, address, income, education, and employ. All the variables have p-values of 0.0000 thus age, address, income, education, and employ are the potential candidate for the final model since the p-value is less than our cut-off value of 0.2. But we get different result in case of reside. We consider the Chi-squared test for reside which has a p-value of 0.5413 thus reside is not a potential candidate for the final model since the p-value is more than our cut-off value of 0.2. The log-rank test of equality across strata for the predictor marital has a p-value of 0.0136, thus marital will be included as a potential...
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...Lecture 12: Introduction to Survival Analysis In many biomedical studies, the outcome variable is a survival time, or more generally a time to an event. We will describe some of the standard tools for analyzing survival data. Most studies of survival last a few years, and at completion many subjects may still be alive. For those individuals, the actual survival time is not known – all we know is how long they survived from their entry in the study. Similarly, certain individuals may drop out from the study or be lost to follow-up. Each of these cases is said to be censored, and the recorded time for such individuals is their time until the censoring event. Example: HPA staining for breast cancer survival We consider data from a retrospective study of 45 women who had surgery for breast cancer. Tumor cells, surgically removed from each woman, were classified according to the results of staining on a marker taken from the Roman snail, the Helix pomatia agglutinin (HPA). The marker binds to cancer cells associated with metastasis to nearby lymph nodes. Upon microscopic examination, the cancer cells stained with HPA are classified as positive, corresponding to a tumor with the potential for metastasis, or negative. It is of interest to determine the relationship of HPA staining and the survival of women with breast cancer. The survival times in months Ti and staining results (xi = 0 for negative and xi = 1 for positive) for the 45 women are presented in the following table. Also included...
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...Classroom management is a highly emotive and at times spurious phrase. It conjures up many images and experiences in which there are abundant publications bursting with competing theories, applications and never-ending analysis. Google the phrase and over 100,000 pages are listed with various approaches that range from common sense applications to profound theoretical dissertations on the subject (50 ways to handle the difficult class, 10 ways to deal with defiant students, Managing excessive talking successfully, etc...). However, disruptive behaviours in the classroom have real costs including: • distracting other students and the teacher in class • reducing student involvement in the learning process • lowering other students' motivation in or out of class for that particular subject • influencing fairness in assessment • using the teacher’s teaching time unproductively • teacher and students experience a lack of respect Porter (2007)[1] draws down on all the competing theories of classroom management and summarises five/six approaches which take in holistic, constructive, preventative and remedial strategies. These approaches include: • Limit-setting approach-Canter & Canter • Applied Behaviour Analysis • Cognitive-behaviourist approach • Neo-adlerian theory- Rogers • Humanism • Choice theory-Glasser Porter argues that when considering the effectiveness of each theory one should question...
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... The most notable theory from this time the Socratic Method, which consists of posing probing questions to students rather than espousing a hierarchy of knowledge. Brief History of its Founding Modern theories such as behaviorism, founded in the early twentieth century, are associated with theorists including Watson, Skinner, Pavlov and Thorndike. Watson known as the father of behaviorism proposed an alternative to the views of Wilhelm Wundt the founder of the discipline of psychology in1879. (Moore, 2011, p. 1). According to Moore, “Wundt assumed that the study of consciousness or subjective mental life was the appropriate subject matter for psychology.” (Moore, 2011, p. 1, para.1). Watson proposed that study and analysis should focus on observable behavior and that concerns with consciousness only hampered the process. (Driscoll, 2005, p. 31)...
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...Instructor’s Manual with Test Items to accompany Applied Behavior Analysis Second Edition John O. Cooper ● Timothy E. Heron ● William L. Heward All, The Ohio State University Prepared by Stephanie Peterson, Idaho State University ● Renée K. Van Norman, University of Nevada-Las Vegas ● Lloyd Peterson, Idaho State University ● Shannon Crozier, University of Nevada-Las Vegas ● Jessica E. Frieder, Idaho State University ● Peter Molino, Idaho State University ● Heath Ivers, Idaho State University ● Shawn Quigley, Idaho State University ● Megan Bryson, University of Nevada-Las Vegas ● David Bicard, University of Memphis [pic] Upper Saddle River, New Jersey Columbus, Ohio ____________________________________________________________ ______________________ Copyright © 2007 by Pearson Education, Inc., Upper Saddle River, New Jersey 07458. Pearson Prentice Hall. All rights reserved. Printed in the United States of America. This publication is protected by Copyright and permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form or by any means, electronic, mechanical, photocopying, recording, or likewise. For information regarding permission(s), write to: Rights and Permissions Department. Pearson Prentice Hall™ is a trademark of Pearson Education, Inc. Pearson® is a registered trademark of Pearson plc Prentice Hall® is a registered trademark of Pearson Education...
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...his daughter Deborah and named the air bed or the Skinner tender that was intended to help his wife ease some of the parenting duties such as waking in the middle of the night to add blankets to a cold baby, later sparked a backlash of criticism of Skinners work and false rumors about Deborah committing suicide. According to “B.F. Skinner Foundation” (2013) In 1938, Skinner wrote The Behavior of Organisms which “summarizes nearly ten years of research, spanning the years of Skinner's graduate school days at Harvard through his three years as a member of the Society of Fellows.” In 1945, Skinner became the Psychology Department Chair at the University of Indiana. Three years later he joined the psychology department at Harvard University where he remained for the duration of his life. It was at Harvard where Skinner’s inventions helped to shape his career in psychology and helped him to become one of the leaders in behaviorism. Behaviorism according to Dictionary.com (2013) is “the theory or doctrine that human or animal psychology can be accurately studied only through the examination and analysis of objectively observable and quantifiable behavioral events, in contrast with subjective mental states, in contrast with...
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...OSB: Chapter One Chapter one of Opening Skinner’s Box focuses on the namesake of the book, B.F. Skinner. The experiments described all focus on Skinner’s primary study, that of ‘operant conditioning’. Skinner brought into question the concept of free will, instead believing that all human decisions are the result of consequences, both positive and negative. He felt that through a system of positive reinforcement, entire countries could be changed to compliant citizens. In fact, the book tells us, he openly admitted that he hoped to one day use his studies for fascist goals in the nation. His primary experiment was conducted on rats that he placed in a box, and taught to step on a treadle to receive a food pellet. He experimented both with consistency, intervals, and random deliverance of the food and found that the rats did not cease to rely on the process to gain food. However, after cutting off the rewards, he found that the rats did indeed stop their efforts. Although the author of the book proceeds to interview esteemed colleagues who believe firmly in free will and dismiss Skinner’s theory, the overall mystery of the experiment remains. At first I was thrilled by the chapter and excited by the meshing of the author’s artistic writing and the scientific experiments and interviews she describes. However, I must say I enjoyed the project far less when writing a summary of the mere experiment. As a reader and student, the author’s style and stories added and enriched my experience...
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...Synopsis Skinner addresses operant behavior in this article. Operant behavior refers to behavior that operates on the environment or is controllable by the individual. Skinner suggests that operant behavior usually affects the environment and generates stimuli which “feed back” to the organism. This feedback can be a reward and/or punishment (Skinner, 2012, p. 55). Skinner investigates this by using an aluminum box divided into two compartments. In one compartment, a pigeon is able to peck a translucent plastic plate behind a circular opening which is a delicate electric key. When pecked, the circuit is closed to operate recording and controlling equipment. Colored lights can be projected on the back of the plate as stimuli (Skinner, 2012, p. 54). Operant reinforcement is demonstrated when food is given to the pigeon when it pecks the key, which created the high probability of responding. If the food is not given when the pigeon pecks the key, the rate declines or may even stop all together. This is called operant conditioning or extinction. What happened when intermittent reinforcements, like fixed ratio or variable ratio reinforcement was used? This is where reinforcements are based on time and/or counters. Skinner relates this type of reinforcement to our everyday life and how few of the things we do always “pay off”. The dynamic characteristics of our behavior depend upon the actual schedules of reinforcement (Skinner, 2012, p. 55). The colored lights in the...
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...learning in which animals is from the behavior or the way it acts witch also depends on its environment. In this behavior the animal would either increase or decrease by the following reinforcement that follows. Animal trainers apply Operant conditioning, if the animal performs a behavior that they want done again or the trainer will also give them a treat for doing this behavior. Humans learn in the same way for example if your teenager is supposed to come home from high school every day and/or chores around the house making the bed, washing close, doing dishes, vacuuming, if you do not reward her for this positive reinforcement will not follow and will probably stop altogether doing the chores around the house when she comes home from school. Positive reinforcement- when an animal does a behavior produces a positive stimulus if you reinforce the positive stimulus and you give the animal a treat then later on the animal is likely to always do the same favorable behavior over and over. The positive stimulus will know that you gave it positive reinforcement and will probably do the same behavior over when you like the animal to do it. Negative reinforcement this involves taking away the unfavorable stimulus, or in this case a negative reinforcement will increase what you would like the child not to do again and again. This is not like a punishment because punishments follow consequences good ones and bad ones. Positive reinforcement for a behavior that you want to happen again whenever...
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...important historians to psychology, his work led to the development of behavior modification and behavior therapy which is a model that psychologist continue to apply and modify today. In the beginning with the social need for efficient psychotherapy soon developed a solid theoretical body of behavioral laws, Skinner indicated that in order to develop the appropriate path towards efficient intervention for unadaptive behavior new theories regarding about abnormal behavior and as well as procedural model for evaluations (Labrador, F. (2004). Behavior therapy continued to nourished by developments through experimental psychology, Skinner’s treatments offered many opportunities not just clients but as well researchers/psychologist to explore the newly lens developed. However, behavior modification and therapy had its limitation yet today it continues to have some modification still needed to be implement, it said that in order to acknowledge and pay a tribute to Skinner’s work is to overcome these limitation and further develop behavior therapy into an effective model (Wilson, G., & Agras, W. (1992). Rise of behavior modification & therapy The development of behavior modification and therapy was backed up by the work of Skinner, his techniques and experiments were based in operant conditioning and specifically practical developments that were all Skinner’s work (Labrador, F. (2004). The development of both behavior modification and therapy techniques came even before these two models...
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...situations. He put a rat in Skinner box and the rat would pull the lever, which in result the rat would receive food. The rat then realized that each time it pulled the lever; food will come out so it constantly kept pulling the lever (Wikipedia). Skinner's theory on punishment is that a positive reinforcement is more effective in changing and developing behavior than by using any form of punishment. Skinner believed that the main thing to learn from being punished is to avoid punishment altogether. Reinforcement is a concept in behaviorism and a common confusion is that negative reinforcement is synonymous with punishment. Positive reinforcement is strengthening the behavior while negative reinforcement is strengthening of behavior by removal of avoidance of an aversive event (Wikipedia). Although both types of reinforcement strengthen the behavior or either promotes the probability of the behavior to reoccur. One of Skinner's favorite experiments involved the pigeon and it was to demonstrate superstition. The bird would behave as if there was a casual relation between it’s behave as if there was a casual relation between its behavior and the presentation of food even when the relation was lacking. There are many...
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...useful devices like the cumulative recorder, even in his old age he invented a thinking aid to help with writing. Skinner showed the positive reinforcement by placing a hungry rat in the Skinner box. This box contained a lever with food as the rat moved inside the box the lever would drop the food to a container next to it. The consequence was that the rat would repeat the behavior again and again. A good example to picture this would be thinking of a daily basis situation every time you do something good you get a reward, so then the same action becomes a daily thing so you can get rewarded more often. The negative side is that if one day you don’t do the right thing then you won’t get reward and then the habit might be broken. The opposite of reinforcement is punishment this can also work directly by doing something unpleasant stimulus. For example if the children don’t behave then they get put in time out and they won’t get to do something they enjoy. Superstitious behavior arises when the delivery of reinforcement and punisher occurs close together in time with an independent behavior. For example bad luck you do something and then something bad happens. After many years of contribution to psychology F. B Skinner died in 1990 at the age of eighty six years old. In 2002 he was the most...
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...west Tennessee. QCBS is expecting a 100 percent increase in the total amount of clients served. West Tennessee currently has 12 behavior support and management agencies that provide services for individuals with intellectual and developmental disabilities and 5 that specialize in autism, as well as more than 20 residential service providers. The total amount of clients served by residential providers exceed 4500 with a waiting list that surpasses 2300 individuals that have been evaluated and are in need of services. Many of these future service recipients are located in mental health institutions while others are misplaced in array of nursing homes located in west Tennessee. QCBS has only been in business one year and is anticipating an increase in the budget for the total amount of service recipients served, or an additional $25,000. QCBS marketing initiative has the following objectives. * Maximize limited marketing monies to improve the exposure of their agency. * Increase the operating budget by 50% while maintaining current contracts at competitive prices. * Increase the number of potential service recipients by providing site observations and evaluations. Strengths QCBS has various resources that will encourage and support its initiative to increase the total amount of service recipients receiving behavior supports. The owner of the company worked at the West...
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