1.introduction引言
在宏观经济理论以及在微观经济理论中有一个流行的概念是边际变化。因此,边际分析是经济理论中最重要的原则之一,而且这个概念必须和几个概念同时研究才可以进行。边际变化可以解释为一个小的比例中的加法或减法,对总数的影响。另一方面,在相关的经济变量关系的研究上边际分析可以描述为分析或所带来的边际变化,至于微观经济理论边际概念主要是用以阐明几种不同形式的优化行为。
A popular concept that is used both in macro economic theory, as well as in micro economic theory is that of marginal change. Marginal analysis is therefore one of the most important principles of economic theory, and one must study a few concepts of economic theory before one can proceed. Marginal change can be explained as a small addition or subtraction, in proportional comparison, to the total quantity of some variable. On the other hand, marginal analysis can be described as the analysis or the study of the relationships that are brought about by marginal changes, in related economic variables. As far as micro economic theory is concerned, marginal concepts are utilized primarily in order to explicate several different forms of optimizing behavior. For example, while customers are stated to be maximizing their utility or their satisfaction, companies are stated to be maximizing their profits.
从本质上说,在经济理论上,往往是因为目前人类只有数量有限的可用资源,所以作为一个年限有限的理性人,这意味着必须作出某些艰难的选择。而且这可能意味着,每次都是一个被迫作出的选择,别的东西必须放弃。在边际理论和边际分析的基础上,经济理论提供了赖以立足一个人的决定,即:最好的决定可以有效地权衡参与作出经济决策的边际成本边际收益进行。必须记住的是,经济理论也往往是基于哲学的“功利主义” ,重申对“最大的善的最大数量”的原则。
In essence, it is often stated in economic theory that where there are only a limited number or quantity of resources available, one cannot obviously have everything that one would want, and this means that certain tough choices must be made. This can mean that every time one is forced to make a choice, something else must be given up. Economic theory on the basis of marginal theory and marginal analysis offers one a framework upon which to base one’s decision: for example, the best decision can be made by effectively weighing the marginal benefits against the marginal costs involved in making an economic decision. It must be remembered that economic theory is also often based upon the philosophy of ‘utilitarianism’, which reiterates on the principle of “the greatest good for the greatest number”. This can be explained by stating that one must be able to make a decision based on the objective of maximizing societal welfare through the decision. It must be noted that although this type of choice may be easy at times, it may be extremely difficult at other times.#p#分页标题#e#
2.main body 正文
Take for example a customer who is in the process of deciding what sort of new car he must purchase. This person would make his decision based on what he likes best, provided it stays within his fixed budget. This can mean that this customer would have maximized utility by managing to purchase the things that he likes the best. This example is a simple utilization of the utilitarian principle. At times, it may not be so easy; for example, when one is in the process of deciding an issue on healthcare. Must the elderly be denied vital health care just so that the young can avail of better health care? Similarly, must the urban children have better educational facilities, at the cost of depriving rural children of basic education? This means that the principle of the ‘greatest good for the greatest number’ would be directly related to how one describes and quantifies ‘good’, and in order to understand these ideas better, it is imperative to understand first the concepts of marginal costs and marginal benefits. Marginal costs, that is, the additional costs that are imposed when one more unit of a product is manufactured or produced can be explained by using this example: if the cost of making nine pieces of pizza is $90, and the cost of making 10 pieces is $110, then this would mean that the ‘marginal cost’ of producing the tenth piece of pizza is $20. This means that total costs will always increase whenever production increases, although marginal costs may not rise at the same time.
When marginal costs rise, it can be explained with an example: when a firm becomes very large, the costs rise, at the same time that the difficulties of managing the organization increase. it can be further explained by another example: when a mandate is passed that the air and the environment must become cleaner, the task is quite simple and easy at the outset, because the dirtiest cars can be pulled off the roads. However, after this task has been accomplished, the mission becomes more and more difficult, and newer technology may be needed to continue the process. Therefore, it is obvious that marginal costs would rise. Marginal benefits, on the other hand, can be explained as the marginal benefits or advantages that one would obtain when one more unit is produced. These benefits can be expressed in two manners: units of utility, or satisfaction with the product.
Therefore, it is obvious that economic choice in general almost always involves some sort of adjustment to the already existing situation, or the status quo. For example, the manager of a school may be trying to decide whether he must hire a new teacher for English, or not, or, an individual, after having finished his dinner at a restaurant, may decide whether he wishes to have dessert or not. This explains the theory that economic choice is almost always based on a comparison of the expected marginal benefits and the expected marginal costs of the choice under consideration at that particular point of time, a choice that would change the present situation, for better or for worse. As mentioned earlier, in a world of scarcity, with the limited choices and options available to an individual or a group, the decision to obtain marginal utility or benefits within the process of making a choice can be very important indeed. However, one surprising element that has arisen out of the study and analysis of decisions based on marginal analysis is that there can actually be ‘too much of a good thing’.#p#分页标题#e#
For example, services like health care or education appear to be inherently desirable to an individual or association, but at the same time, it is a fact that too much of these services may be produced. The idea of ‘too much’ occurs when one is able to obtain additional amounts of the services at a rate that may exceed the marginal costs, even though it may be true that the marginal benefits may exceed them. This can mean that one is in the process sacrificing alternative goods and services that may have been available at the margin, that is, in other words, the place at which one considers the final lists of a product or service. It can be stated therefore, that marginal analysis can be used to help people to allocate their scarce resources in such a way that they would be able to maximize the output, or in other words, greatly enhance the value that they may have hoped to produce or obtain. In this context, marginal analysis, a technique widely and popularly used in making wise and practical business decisions, can be explained as the analysis of the benefits and the costs of the marginal unit of a good, or of an input, for example, margin = next unit, while net benefits = total benefits – total costs. In this situation, it is obvious that most individuals would wish to make the maximum net benefits.
The control variable, an important component in a marginal analysis theory, is the variable that can be changed as required. For example, the control variable may be the quantity of a good that one buys, or it may be the quantity of the output that one would be able to produce, or it may refer to the quantity of an input that one uses in order to produce the output. Marginal analysis in this context concentrates on the aspect of whether or not one must take the risk of increasing the control variable by one single unit or not. Experts define the process in which to conduct an effective and efficient marginal analysis: first and foremost, it is important to define the control variable involved. Second, one must identify what the increase in the total benefits would become, if one were to add one more unit of the control variable. This can be explained as the ‘marginal benefit’ of the added unit. Third, one must be able to determine what the increase ithe total cost would be, if one were to add one more unit of the control variable. This would comprise the ‘marginal cost’ of the newly added unit Fourth, if it were found that this unit’s marginal benefits were to exceed or at the very least, to equal its marginal costs, then it must be added. One may be able to apply economic theories of marginal costs and marginal benefits in a practical manner to a typical consumer purchase decision making process. At the outset, it must be remembered that a consumer makes several types of economic decisions on a daily basis, in which he makes decisions on how he must spend his limited or scarce income on the acquisition of goods and services. He would be faced with deciding whether he must spend all his available resources on goods or services, or whether he must save some of his income so that he would be able to finance some of his needs of his future. When he is taken as a labor resource, he must make the decision whether he must use his time in working for his pay, or whether he must spend it on sleeping and other leisure time activities. Similarly, when he is a labor resource, he must decide how much of his time he must spend on education, so that he may be able to maximize his life earnings. On the other hand, if he were an entrepreneur, then he must make the decision on how many people he must hire, or how much he must spend on acquiring a new product or service, which would help him increase production. In short, it is obvious that all economic decisions yield certain benefits to, and also at the same time impose certain costs on the decision maker involved in the decision making process. If the decision maker were to follow a simple rule, which is: continue to engage in a particular activity, as long as the marginal benefit seems to be greater than or equal to the marginal costs.#p#分页标题#e#
The best and optimal decision would take place when the marginal benefits were to equal marginal costs, thereby enabling the decision maker to make the best use of the resources that he has at his disposal when he has made his decision. Another example of the practical application of economic theory and marginal analysis would be that of the agricultural researchers and analysts of Florida who have used economic analysis in the decision making process that they have had to indulge in when they had to decide whether to use alternative agricultural technologies that would improve their income. This can be compared to previous years when agriculturists almost never used economic theory and the concepts of marginal benefits and marginal costs to make their decisions in this sector. Today, when economic theories are applied, agriculturists consider how the proposed new technologies and all the associated risks, for example, would impact the profitability of using the new technologies. To conclude, it must be said that economic theory can be applied in any sector, and especially in areas where one wishes to analyze one’s profits against one’s investments. Today, more and more people have started to apply these practical theories within their organizations and even otherwise, and thereafter, enjoying the benefits of such analyses.
A phobia is an irrational, intense, persistent fear of certain situations, objects, activities, or persons. Phobia is also used in a non-medical sense for aversions of all sorts. Fear is an adaptive human response to danger. It serves a protective purpose, activating the “fight-or-fight” response of the sympathetic nervous system. When faced with danger, our sympathetic nervous system produces adrenaline. This excess adrenaline prepares us to fight or to flee the physical threat. The fight-or-flight response includes an increase in heart rate and blood flow to our large muscles, better enabling us to react to the emergency. Blood sugar also increases, providing us with more energy. With our bodies and minds alert and ready for action, we are able to respond quickly and protect ourselves. Phobias are more often than not linked to the amygdala, an area of the brain located behind the pituitary gland in the limbic system.
The amygdala secretes hormones that control fear and aggression, and aids in the interpretation of this emotion in the facial expressions of others. Most psychologists and psychiatrists classify most phobias into three categories: Social phobias-fears involving other people or social situations; Specific phobias-fear of a single specific panic trigger; Agoraphobia-a generalized fear of leaving home or a small familiar ‘safe’ area. 2 Common phobia symptoms and sensations include shortness of breath, palpitations, pounding heart or accelerated heart rate, chest pain or discomfort, trembling, feeling of choking, sweating nausea or stomach distress, fear of dying, numbness and fear of fainting. 3 Arachnophobia (from Greek arachne, “spider” and phobia “fear”) is a specific phobia, an abnormal fear of spiders and sometimes other arachnids, such as scorpions and harvestmen. It is among the most common of all phobias. The reactions of arachnophobics often seem irrational to others (and sometimes to the sufferers themselves). People with arachnophobia tend to feel uneasy in any area they believe could harbor spiders or that has visible signs of their presence, such as webs. Arachnophobia is, in many cases, the result of a traumatizing encounter with spiders in one’s early childhood, though the experience may not be remembered. One view, especially held in evolutionary psychology, is that the presence of venomous spiders led to the evolution of an innate fear of spiders or made acquisition of a fear of spiders especially easy. Like all traits, there is variability in the intensity of fears of spiders, and those with more intense fears are classified as phobic.#p#分页标题#e#
3.conclusion结论
The most frequently used form of therapy for the treatment of specific phobias is a type of cognitive behavioral therapy (CBT) called systematic desensitization or exposure therapy. In desensitization or exposure therapy, you are exposed in a safe and controlled way to the object or situation you fear. The most commonly used exposure therapy involves gradual encounters with the fear-producing object, first in the imagination and then in reality. For example, if you have a spider phobia, you would first imagine seeing a spider, then view photos of spiders, and finally look at a spider in real life. Cognitive psychologists believe that we must venture into the realm of mental processes in order to understand human nature. Behaviorists believe that our actions are conditioned by our past experiences and situations, rewards, and punishments, rather than by conscious choice. Combining these two theories gives us the Cognitive-Behavior approach, or CBT. Research has shown that CBT can be effective for several anxiety disorders, in particular panic disorder and social phobia. Anti-anxiety or anti-depression medications can be of assistance in many cases. Benzodiazepines could be prescribed for short-term use. Some of the newest antidepressants used to treat phobias are called selective serotonin reuptake inhibitors (SSRIs) and include Fluoxetine, sertraline, fluvoxamine, paroxetine, and citalopram. Prozac, Lexapro and Zoloft are also SSRIs.
Psychotherapy involves talking with a licensed mental health care professional such as a psychiatrist, psychologist, social worker, or counselor. Techniques used during psychoanalysis may include free association, dream analysis, and analysis of the relationship between the patient and the therapist. Energy psychology is a new approach to therapy that dramatically reduces emotional distress and restores emotional well-being by clearing the flow of the body’s “energy system.” Energy Psychology is also known as “energy-based psychotherapy,” or simply “energy therapy”. It has been very effective in treating phobias because it is safe, effective and long lasting. Hypnotherapists help their clients go into a deep state of relaxation. While in this state, the conscious mind is less active, and the therapist is able to directly suggest ideas, concepts, and lifestyle changes to the patient’s subconscious mind. The goal of hypnotherapy in phobia treatment is to reprogram the patterns of negative behavior. Self-support techniques include yoga, meditation, aerobic exercise, strength training, relaxation techniques and proper nutrition. The yoga form of treatment comprises asana hatha yoga, pranayama, meditation and yoga nidra, which help in balancing your nervous system, endocrines, generates energy in your body and calms your mental and physical health.
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