Hereditary Component Analysis for MS

Hereditary Component Analysis for MS The family and twin studies provide evidence of the presence of an important hereditary component in the etiology of MS, with percentages of heritability ranging from 24% to 31.6% (Bellia et al., 2009; Lin et al. ., 2005; Oneill et al., 2015). Among the etiopathogenic models to explain the origin of MS, partial lipodystrophy, which results from mutations in the LAMINA A / C (LMNA) genes or the peroxisomal proliferator activated receptor (PPARg) gene, is a paradigm of genetic processes Involved (Hegele and Pollex, 2005). The PPARg gene, which is involved in the processes of differentiation and functioning of adipocytes, is believed to be related to the etiopathogenesis of obesity (Ristow et al., 1998; Moustafa and Froguel, 2013). Specifically, the ÃŽ ±-form of PPAR is believed to play an essential role in the origin of MS, since it regulates the oxidation and transport of fatty acids and the generation of lipoproteins (Guan and Breyer 2001, Tan, Zhuang and Wahli, 2017). PPARÃŽ ³ is a key regulator in the process of adipogenesis and its increased function results in increased body mass, whereas decreased activity induces weight loss and the development of IR ( Deeb et al., 1998, Majid et al., 2016). The adiponectin regulatory gene (APN gene), a hormone involved in the regulation of energy homeostasis, and glucose and lipid metabolism, could induce IR by reducing the synthesis of this hormone (Maeda et al. , 2002; Yamauchi et al., 2003). Plasma adiponectin levels are inversely related to body mass and may have an important protective role against MS because of its anti-inflammatory, antioxidant and antiatherogenic effects (Esfahani et al., 2015). In addition, certain genetic polymorphisms have been identified for this gene that are related to the synthesis of insulin, IR and DM (Filippi et al., 2004). The CD36 receptor gene for thrombospondin, whose function is to bind and capture fatty acids to be used by other tissues, is also a candidate in the etiopathogenesis of MS (Love-Gregory et al., 2008; Zhou et al., 2016 ), Since we know that fatty acids induce IR, obesity and inflammation (Roden, 2007). It is described that CD36 deficiency causes an imbalance in glucose levels in response to insulin, as well as higher levels of fatty acids, TR, fasting glucose and blood pressure (MA) (Ma et al., 2004: Pioltine et al. Al., 2017). The enzyme 11 beta-hydroxysteroid dehydrogenase type 1 (11ÃŽ ²-HSD1), whose function is to interconvert 11-inert ketosteroids, cortisone and 11-dehydrocorticosterone (11-DHC), to its 11-hydroxy active forms, cortisol and corticosterone. 11ÃŽ ²-HSD1 is considered to have an important etiological factor in obesity. Although circulating concentrations of glucocorticoids are not elevated in prevalent forms of human obesity, locally enhanced glucocorticoid response in skeletal muscle and adipose tissue has been implicated in MS (Walker, 2007; Cai et al., 2016) . Clinically, RI and HT are associated with increased messenger RNA alpha glucocorticoid receptors (GRÃŽ ±) and the number of receptors in skeletal muscle, and a positive association between messenger RNA levels for both GR Such as 11ÃŽ ²-HSD1 in skeletal muscle for the condition of insulin resistance (Seckl, Morton and Chapman 2004; Freude et al., 2016). Î’-adrenergic receptors regulate the lipolysis and metabolism of free fatty acids. The ÃŽ ²3-adrenergic receptor (ÃŽ ²3AR) is a candidate gene for abdominal obesity and is related to visceral fat (Krief et al., 1993; Chen et al., 2015). Increased ÃŽ ²3AR function leads to increased catecholamine-induced lipolysis in the visceral fat of subjects with abdominal obesity, as well as to a lower metabolic rate and a lower activity of the resting sympathetic nervous system, all of them characteristics of MS (Shihara et al. Groop and Orho-Melander, 2001, Luglio, Sulistyoningrum and Susilowati, 2015) The Calpain-10 gene (CAPN10), which encodes the corresponding protein, has been associated with an increased risk of DM and RI becoming a strong candidate in the pathogenesis of MS (Orho-Melander et al., 2002; Loya Mà ©ndez Et al., 2014). It is also related to hypertension (Chen et al., 2007), overweight and obesity (Orozco et al., 2014), high cholesterol (Wu et al., 2005) and elevated triglyceride levels (Carlsson, Fredriksson et al. Groop, 2004), all components of the syndrome being analyzed. Another scientific work found in a haplotype of the polymorphism of this gene a risk factor for MS in patients with DM (Kang et al., 2006). It also establishes association with two indicators of the presence of IR, such as high glucose levels after a tolerance test and with HOMA values of RI (Saez et al., 2008). Other genes possibly implicated are those that encode the C-reactive protein, the best inflammatory biomarker, a characteristic of MS and also a predictor of CVR (Devaraj, Singh and Jialal, 2009), as well as the encoder of substrate 1 Of the insulin receptor (IRS1), whose mutations are associated with DM and IR (Kubota et al., 2000). In any case, the genetic ethiopatology leaves unresolved the controversy regarding the predisposing causative factor of MS, since in the scientific community there are defenders of the IR as the main factor involved, while others are inclined to obesity and metabolic dysfunction Of lipids as the most important agent (Alberti et al., 2009; Dragsbà ¦k et al., 2016; Gluvic et al., 2017).

Marijuana Exploratory

Jamal Mujaddidi English 205 Professor Jay 8 April 2010 Exploratory Essay Legalization: Good or Bad? As part of the Marijuana Tax Act of 1937, Marijuana for all purposes was outlawed nationwide. Prior to this Act, over 30 states had prohibition laws towards Marijuana because farmers who employed mainly Hispanic workers complained that this drug would cause people to become â€Å"slow† or â€Å"lazy† and would also cause the users to become addicted. Besides the popularity among this crowd, marijuana was used as an intoxicant during the 1850’s through the 1930’s and was listed in the United States Pharmacopeia. The active ingredient in marijuana is THC, or delta-9-tetrahydrocannabinol, but this is only one of the 400 other chemicals that are in the plant (TheWELL). It was prescribed for conditions such as labor pain, nausea, arthritis, and rheumatism (DeLisle). It was only after individuals began committing crimes while under the influence of Marijuana that the U. S. Federal Bureau of Narcotics gave marijuana the image of a powerful, addicting, substance that would lead users into a more serious addiction. In the 1960s, it was mainly used by college students and â€Å"hippies,† and subsequently became a symbol of rebellion against authority. Marijuana use became a commonplace issue in congress which led to The Controlled Substances Act of 1970 which classified marijuana along with LSD and heroin as S1 drugs, otherwise known as substances which have the highest relative abuse potential and no form of medical use (DEA). Widespread eradication of marijuana and marijuana products began. The current opponents of marijuana legalization claim that marijuana does have addictive qualities and is an epidemic on America’s youth. This crowd presents that marijuana is a â€Å"silent-killer† due to a fungus and mold which can easily grow on the part which is smoked by users (PRNewswire). This fungus can cause lung cancer and they have deemed marijuana as bio-hazardous. The opposition also goes to say that marijuana can have adverse effects on the brain and can cause brain-cells to die. Some research suggests that use of marijuana during pregnancy can result in premature birth and low birth weights and can even cause temporary loss of fertility. Along with adverse effects on the reproductive system, the opposition claims that marijuana use during adolescence can be harmful to physical and sexual development. This side pushes for further prohibition of marijuana and stricter punishments due to their beliefs that the negatives outweigh the benefits. In the middle of this debate, stand the moderate marijuana use supporters. This side views marijuana use as a potential alternative to painkillers which are detrimental to vital organs. This crowd is mainly made up of physicians and health-care professionals, as wells as patients of chronic illnesses and pain. Doctors and nurses say that cannabis is a less toxic and less expensive medicine for diseases such as multiple sclerosis, Crohn’s disease, migraines, cancers, and many other disorders which cause chronic symptoms and pain. This side also states that marijuana’s versatile nature allows patients to gain the pain relieving effects through ingestion, canceling out the negative effects of smoking. Besides all these benefits, this crowd pushes for a safe, reliable and quality-controlled source of marijuana which can only be achieved through legalization. It is believed that after this source is created, many adverse effects of â€Å"bad† marijuana will disperse. Another camp of this debate is the supporters of full legalization of marijuana use and growth for medicinal and recreational use. These supporters claim that marijuana should be allowed to be used in the way alcohol and cigarettes are used recreationally. They state these comparisons have worse long-term effects than THC and yet they are taxed and regulated. Another point they make is that marijuana would inject millions of dollars into the economy once government grown marijuana is taxed. Besides the smoking and ingesting of the drug, the plant can be used for its naturally produced fiber known as hemp. This can be cultivated from the stem of the plant and used commercially and industrially for paper, textiles, biodegradable products and medical purposes. Overall, they believe the claimed dangers of marijuana are exaggerated and not enough medical trials have been done to verify these claims. As a college level youth and the Legalization of marijuana use in California is on the ballot, I am interested in learning about this issue before I cast my vote. I have seen the benefits of medicinal marijuana in my family and can attest to the pain relieving effects. As for the recreational use, I believe that alcohol is a much more dangerous substance that can be detrimental to mental and physical health and cause irrational decisions while under the influence. Prohibition has shown to not be a viable solution in the past and I don’t think it can ever solve anything. Regulation on the other hand can prove to be effective because substances will not be bought and traded illegally. I think the legalization of marijuana will improve lives, decrease crimes, and slightly improve the economy. Works Cited DeLisle, Judi. _Medical Marijuana Research Guide. Valencia West Campus Library_. Web. 20 Mar. 2007. 7 Apr. 2010. â€Å"DEA, Controlled Substances Act. † Welcome to the United States Department of Justice. Web. 08 Apr. 2010. â€Å"The Marijuana Initiative Is a Silent Killed and It Should be Defeated – Los Angeles, March 25/PRNewswire/. †_PR Newswire: Press Release Distribution, Targeting, Monitoring and Marketing. _Web. 08 Apr. 2010. â€Å"Fact Sheet – Marijuana. † The WELL – The Birthplace of the Online Community Movement. Web. 08 Apr. 2010.

Essay on Alzheimers Disease - 813 Words

Topic: Alzheimer’s Disease Specific Purpose: To help my audience understand what Alzheimer’s Disease is. Thesis Statement: The need to educate people on Alzheimer’s Disease for family members or friends in-case a loved one is diagnosed. Introduction: A. What would one do if their family member or friend knew of someone who was diagnosed with Alzheimer’s Disease? What would they do to help or take care of this family member? Well, I work in a nursing home with the elderly with this disease every day. It can be a challenge for the family member who may not understand, but with a little education on Alzheimer’s Disease, it can help the family member see the world through the patient’s eyes. B. This person could be a†¦show more content†¦Alzheimer’s disease progresses in stages over 8 to 10 years. These stages are Mild, Moderate, and Severe Alzheimer’s Disease. a. Mild Alzheimer’s Disease includes memory loss, trouble naming items, getting lost easily, and may have personality changes. b. Moderate stages include poor memory recognition, trouble handling tasks, have a hard time dressing, may argue, be depressed, worried, and even wonder off. c. In the last stage, people with severe Alzheimers have problems eating, talking, and not recognizing family members. They must rely on caregivers to handle their most basic needs, such as holding their heads up to eat. (As you can see, it is important to understand what Alzheimer’s Disease is, So now, let me give you some safety tips on caring for the Alzheimer’s patient) C. Finally, Alzheimer’s Disease can also be dangerous as far as safety. To keep your loved one safe in the home, there are several things that can be done. a. First, try to see the home through the patients eyes. Keep in mind that the Alzheimer patient perceives object and colors differently than we do. b. Make sure the home is free from clutter and other dangerous materials. â€Å"Kiddie gates† should not be used, because they can’t hold an adults weight. c. Another safety pre-caution to take would be to always have a fire extinguisher and detector in the home. Fires can easily be started if pre-cautions are not taken. d. Food andShow MoreRelatedAlzheimers Disease945 Words   |  4 PagesAlzheimer’s Disease Alzheimer’s Disease is a progressive neurological disease; it often attacks the brain tissues causing memory loss of one’s identity and regular behaviors. Statistics indicates that the rate of predicted people to get Alzheimer’s will increase briskly as time goes on. There are currently no cures for such disastrous disease, but there are currently approved treatments available that can help people within the early stages of Alzheimer’s. Once the disease is too far alongRead MoreAlzheimers Disease3170 Words   |  13 PagesThe Role of Caregiving to Patients with Alzheimer’s Disease Megan Zann April 27, 2012 Health Psychology Dr. Ackerman Introduction It is normal to periodically forget your keys or a homework assignment, because you generally remember these things later. However, individuals who suffer from Alzheimer’s disease may forget things more often, but they do not remember them again. The incidence of Alzheimer’s disease has dramatically increased because people are living longer. This is a result ofRead MoreEssay on Alzheimers Disease1503 Words   |  7 Pagesâ€Å"Alzheimer’s disease is a form of dementia that gets worse over time. It leads to nerve cell death, and tissue loss throughout the brain. Over time, the brain shrinks dramatically, affecting nearly all its functions. 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This research explainsRead MoreAlzheimer’s Disease Essay2544 Words   |  11 PagesAlzheimer’s disease defined: Alzheimer’s disease (AD) is a progressive, terminal, degenerative brain disease. It is the fourth leading cause of death in adults and currently affects over four million people in the United States. This number is expected to increase over the next several years as the baby boomers age, until it reaches fourteen million by the year 2025. Alzheimer disease generally occurs in people over seventy five years of age; however it does strike people in their forties, fiftiesRead MoreEssay on Alzheimers Disease2405 Words   |  10 PagesAlzheimers Disease is a condition that affects 50% of the population over the age of eighty five, which equals four million Americans each year. It is becoming an important and high-profile issue in todays society for everyone. 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Also, the high frequency of Alzheimer’s, and the high cost in labor, money, and material of caring for its victims shall put considerable burden on the society as a whole. Here, however, these issues are not going to be debated. Instead the pathology of Alzheimer’s will be reviewedRead More Alzheimers Disease Essay1235 Words   |  5 PagesAlzheimer’s Disease is an irreversible, genetically linked illness. This disease was chosen for the topic of this essay under the consideration that in many families the illness can be incredibly tragic, passing down for generations without mercy. It is not rare to encounter families in which each member is afflicted with a form, mild or severe, of Alzheimer’s. The disease is a progressive brain disease which comes in t wo separate types: Early-Onset Alzheimer’s Disease and Late-Onset Alzheimer’s

The Empirical Evidence On The Disposition Effect Finance Essay - Free Essay Example

Sample details Pages: 10 Words: 2953 Downloads: 10 Date added: 2017/06/26 Category Finance Essay Type Cause and effect essay Did you like this example? Disposition effect, which is studied by many literatures, is one of popular bias of investors. It was firstly suggested by Shefrin and Statman (1985). They gave an explanation of the disposition effect that Investors have tendency to sell winners too early and ride losers too long. Moreover, the result from the experiment of Odean (1998) supported the disposition effect theory. Don’t waste time! Our writers will create an original "The Empirical Evidence On The Disposition Effect Finance Essay" essay for you Create order Odean (1998) compared between Proportion of Gains Realized (PGR) and Proportion of Losses Realized (PLR). PGR can be calculated by dividing realized gains by the sum of realized gains and paper gains and PLR can be calculated by dividing realized losses by the sum of realized losses and paper losses. Realized gain and loss is the gain or loss amount calculated by the difference of sell price and purchasing price when investors sell stocks. Paper gain and loss is an gain and loss amount calculated by the difference between current price and purchasing price for stocks which had not been sold yet. The data was obtained from entire year trade provided by a worldwide discount brokerage house in the period from 1987 to 1990 and from 1991 to 1993 to calculate PGR and PLR. The result showed that PGR values were greater than PLR values in both periods. It means that investors had tendency to realize their gains more than their losses and this was consistent with the disposition effect. Shefrin and Statman (1985) also pointed out about the theories that were possible causes of the disposition effect which are 1) the prospect theory 2) the theory of seeking pride and avoiding regret 3) the theory of mental accounting and 4) the theory of mean reversion. After that, there were many studies discussed whether those theories can be causes of the disposition effect. Next of this report will discuss about those theories and will talk about some interesting factors which affect the disposition effect. Body Start with prospect theory which is the most popular theory which is used to explain the disposition effect, prospect theory was suggested by Kahneman and Tversky (1979). They explained that the prospect theory can be distinguished into two phases which are editing and evaluating. In editing phase, investors compare their choices with the reference point which normally related to their current asset position. The choices which are less than the reference point will be regard as losses and the choices which are greater than the reference point will be regarded as gains. Then, move to evaluating phase, s- shaped valuation function show utility value in vertical line and amount of gain and loss in horizontal line and is concave in gain area and convex in loss area. It will be used for decision making. Investors always choose a choice which gives them the highest utility. Another important point in the prospect theory is losses hurt more than gain. Therefore, investors will be risk see ker in loss area because they want to avoid the losses but they will be risk averse in gain area because they want to ensure that they will exactly get gains. Next, the relationship between the disposition effect and the prospect theory will be explained. Shefrin and Statman (1985) pointed out that prospect theory can be used to explain the disposition effect because when the stocks gain, the investor who act as risk averse will sell those stocks because they want to get gains surely. On the other hands, when the stocks loss, the investors who act as risk seeker, will keep those stocks because they decide to take risk that the price of the stocks could either rise until investors can get the profit or continuously fall that investors get more losses. This characteristic of the prospect theory is consistent with the disposition effect. Weber and Camerer (1998) conducted experiment using purchasing price as a reference point from both last-in, first-out method (LIFO), which is t he method that investors will sell the stock which is bought last, and first-in, first-out method (FIFO), which is the method that investors will sell the stock which is bough first, to compare to selling price, the result showed that the percentage to sell the winning stock is higher than losing stock in both methods. They used the idea that prospect theory can explain the disposition effect to explain the result of their experiment In the prospect theory, disposition effects occur because subjects use their purchase price and are reluctant to recognize losses; they gamble in the domain of losses and avoid risk in the domain of gain. However, there are some comments which show that the prospect theory cannot totally explain the disposition effect. Start with Barberis and Xiong (2009), they pointed out about the case of investor who has prospect theory using annual gain/loss method that investors will be more inclined to sell stocks with prior losses than stocks with prior gains. Investors using annual gain/loss means that investor counted their profit by calculating the price of stock between purchasing price and the price at the reference day such as a half year or a one year later from buying those stocks. Therefore, during the period, it is possible for investors to buy more stocks if they think that stocks will continue to rise in the future or sell them out if they think stocks will continue to fall in the future to accomplish their goal. In their experiment, they divided investment period into three periods which are T0, T1 and T2. T0 is the date investors bought stocks. They showed that even though the stock price fall in time T1 but if they rise in time T2, the overall profit compare between time T2 and time T0 could be small profit. In the same manner, if stocks rise in time T1 and then fall in time T2, investors would get small profit calculated from time T2 and T0. They claimed that since investors were risk averse, they would buy stocks at time 0 if the expected return of stocks were high enough. Therefore, if investors gained in time t1, Baberis and Xiong showed the result from their formula that investor had to buy more stocks for increasing in share allocation to take large gamble that those stocks would rise to get more profit in time T2 than they do so after the stock fall in time t 1 to gamble those stock price would rise and they would get small profit in time T2. Therefore, it contradicts with the characteristic of disposition effect in which investors have a more propensity to sell stocks when stocks rise more than in case that stocks fall. Furthermore, they also conducted an experiment that investigated the share allocation of investors after the stock price rose and fell comparing between using annual gain and loss and realized gain and loss. Realized gain and loss can be calculated each time when stocks price move. The result showed that using realized gain and loss follow the disposition effect more than annu al gain and loss. They gave explanation that using annual gain and loss, investors are forced to accumulate the profit in a single amount in the specific reference time but investors can split to realize their profit in each time the stock price move in realized gain and loss. In case losses, investors do not want to separate their losses in many components while they want to do in case of gain. Therefore, they sell stocks when stocks rise and keep stocks when they fall which was consistent with the disposition effect. Kaustia (2010) raised some different aspect between the disposition effect and the prospect theory. He pointed out that the propensity to sell in the disposition effect is increase or constant when the gain of stocks increase and is constant or insensitive in case of the increase of losses of stock while the prospect theory value function explained that if the gain of the stock price increase, it will minimize the propensity to sell stocks and if the losses of stoc ks increase, it will decrease to propensity to sell. Seeking pride and Avoiding regret is one theory that explains the disposition effect. Shefrin and Statman (1985) argued that investors held their losing stocks because they felt regret to realize the losses and they felt pride if they could close the stock account with a gain. Baraber and Odean (1999) illustrated that since the investor avoided regret, this bias would render investors to sell those stocks when the price of stocks rose because they were afraid that the price of the stocks would fall in the future. On the contrary, if the prices of the stocks they held fell, they would hold it because they expected that the price would rise in the future Third, the disposition effect can be explained by the mental accounting theory. Kahneman and Lovallo (1993) pointed out that investors did not concern in overall profit. All outcomes of an individual investor would be separate into several parts. Thaler (1999) said that invest ors would get more hurt from realized losses than from paper losses. It was painful to close their accounts with losses. Such an incident rendered investor to hesitate to sell stocks of which the price fell. Therefore, mental theory explains the bias of investors in the same way of the disposition effect does. Another causes of disposition effect comes from mean reversion in which Lakonishok and Smidt (1986) as cited in Odean (1998) explained that the investors would sell the winning stocks because they believed that those stocks had reflected the information already and would keep losing stocks because they believed that the information had not incorporated into price of those stocks yet but it would be in the future. There was an experiment to support mean reversion idea from Weber and Camerer (1998). They investigated the reaction of investors after holding the stock two periods. They found that investors had more percentage to sell the stocks if the price of stock at trading date rose in the second period even though it fell in the first period than those stocks of which their price at trading date fell in the second period even though it rose in the first period. However, what investors expect from mean reversion might not be true in reality. To prove this, Odean (1998) conducted the experiment that followed the excess return next 84 days, 252 days (1 year) and 504 days (2 years) after the last trading day of both the winning stocks sold and paper loss stocks. The result clearly showed that the excess return of winning stocks was still positive in all three periods and the excess return of paper loss stocks were still negative in all three periods. Therefore, the result showed us that investors cannot be sure that they would get profit from acting follow mean reversion. However, Kausita (2010) did not agree the idea that the theory of mean reversion can use to explain the disposition effect. She pointed out that investors who followed mean revers ion would sell stocks which had recently risen even though they were paper losses and they would keep stocks which had recently fallen even though they were paper gain. The way investors follow was opposite with the disposition effect. Apart from those theories concern above, there are some factors that affect the disposition effect. The first factor is tax concern which always lessens the power of disposition effect in December. There are many literatures explaining about this topic with various reasons. Shefrin and Statman (1985) pointed out the behavior of investors to realize the loss will happen in December more often than other months as a self control strategy. They explained that investors will normally ride the losing stock but they will have self motivation to realize losses heavily in December which is the deadline of a year to accomplish their tax plan. Odean (1998) also studied about tax effect. He conducted experiment by comparing PGR and PLR by using data in December from 1987 to 1990 and from 1991 to 1993. The result showed that PGR was smaller than PLR in both periods which was the opposite the result when calculating from entire year that PGR was greater than PLR. Odean (1998) wanted to ensure that the difference result came from only tax concern factor, hence, he eliminated rebalancing factor by not including the stocks that sold partially and the stocks repurchased after sold in the experiment, the result still showed that PLR in December was higher than PGR. Therefore, his result stressed the point that investors increased realizing the loss or, in other words, the disposition effect less affect in December because of tax concern not rebalancing issue. Demographic is the second factor that affects disposition effect. Dhar and Zhu (2006) showed that the disposition effect can be affected by the level of income and occupation of investors. They conducted experiment by comparing the disposition effect value among different income level of investors and between investors who work in professional occupation and those who work in non professional occupation. The result showed that high income investors would have lower disposition effect than those with middle income level and middle income investors would have lower disposition effect than those with low income. Furthermore, investors who work in professional occupations would have smaller disposition effect than those who work in non professional occupation. They explained the result that the high income investors had potential to hire financial advisory firm to help them to minimize bias in their investments and investors who work in professional firms presumably had high financial knowledge which led them to minimize their investment bias. They also conducted the same experiment but used information only in December. Disposition effect value in each group in December was smaller than the value calculated entire year which was consistent with Odean (1998) an d the result also showed in the same manner with the above experiment. From the result, it showed that high income investors and those who work in professional occupations would be possibly more concern about tax than those who have middle or low income and work in non professional occupation. Besides, there is evidence show that the house money effect surprisingly coexist the disposition effect even though both of them affect investors in the opposite way. Thaler and Johnson(1990) as cited in Duxbury et al (2011) explained that the house money effect was a bias that investors had a propensity to take more risk after prior gain of their stocks because they included their prior outcomes into current making decision. In other words, investors could be more tolerate to take risk if they got prior gain but they would be more risk averse if they got prior losses. There are many studies showing that the house money effect existed in many stock markets such as in Australia, Taiwan and S weden. Duxbury et al (2011) also supported the issue that the disposition effect and the house money effect coexisted. They compared between PGR and PLR by using data from Chinese stock market from February 2001 to December 2004. The result showed that PGR was greater than PLR if all stocks from raw data were observed. Such an incident means that investors had propensity to sell when stocks gained and kept stocks when they lose. Thus, it was consistent with the disposition effect. They also observed PGR and PLR in case of stocks with prior realized gains and stocks with prior realized losses from the same raw data. The result showed that PGR and PLR in stocks with prior realized gains will be smaller than those in stocks with realized losses. It means that investors hold more stocks after stocks had prior gains than after stocks had prior losses. When investors held stocks, they took risk that the price of stocks would fall in the future. It can be said that investors were more tole rate to take risk after their stocks gain. This was consistent with the characteristic of the house money effect. Therefore, we can find both the disposition effect and the hose money effect in the same raw data but in different point of view. They also conducted experiment to find the correlation between the two effects. They found that there was 53.5% from the sample population had both effect simultaneously and the experiment also showed that the correlation between magnitudes of two effects in group of investors who had two effects simultaneously was highly significant and negative. Duxbury et al (2011) explained that the power of the disposition effect would be weaker because of the presence of the house money effect. In other words, when investors were affected by the house money effect which leaded them to take more risk because of prior realized gain in stocks, they would be less affected by the disposition effect. When investors experienced prior realized losses in stocks, they would be less affected by the house money effect and would be more affected by disposition effect which leads them to be more risk averse. Conclusion In conclusion, the disposition effect which was suggested by Shefrin and Statman (1985) is one of a popular bias of investors. It explains that investors will have tendency to sell stocks if they gain but tend to keep stocks if they loss. Many theories are brought to explain the disposition effect. They are the prospect theory, the theory of seeking pride and avoiding regret, the theory of mental accounting and the theory of mean reversion. Many literatures compare the characteristic of those theories and the disposition effect. Some of them support that those theories can explain the disposition effect. Others show criteria which leads some of those theories to have different characteristic from the disposition effect. Moreover, there are some factors which can affect the disposition effect. Those are tax concern and demographic. Besides, there is evidence from Duxbury et al (2011) showed that the house money effect and the disposition effect surprisingly coexist even though both of them affect investors in the opposite way.