Evolutionary Polynomial Regression

Evolutionary Polynomial Regression Evolutionary polynomial regression (EPR) is a data mining technique based on evolutionary computing that was developed by Giustolisi and Savic (2006). It combines the power of genetic algorithm with numerical regression to develop symbolic models. EPR is a two-step technique in which, at the first step, exponents of symbolic structures are searched using a genetic algorithm (GA) that is the key idea behind the EPR, and in the second step, the parameters of the symbolic structures are determined by solving a linear least squares problem.   The general symbolic expression used in EPR can be presented as follows Where y is the estimated output of the process, m is the total number of the polynomial terms which excludes the bias term a0, F is a function constructed by the process, X is the matrix of independent input variables, f is a function defined by the user, and aj is a constant value for jth term. The first step and key idea in identification of the model structure in EPR is to transfer Equation 1 into the following vector form Where is the least-squares estimate vector of the N target values; is the vector of d=m+1 parameters aj and a0 ( is the transposed vector); and is a matrix formed by (unitary vector) for bias a0, and m vectors of variables. For a fixed j, the variables are a product of the independent predictor vectors of inputs, . EPR starts from Equation 2 and searches for the best structure, i.e. a combination of vectors of independent variables (inputs) . The matrix of input X is given as [15]: Where the kth column of X represents the candidate variable for the j th term of Equation 2. Therefore the jthterm of Equation 2 can be written as: Where, Z jis the jthcolumn vector in which its elements are products of candidate independent inputs and ES is a matrix of exponents. Therefore, the problem is to find the matrix ESkmof exponents whose bounds are specified by the user. For example, if a vector of candidate exponents for inputs, X , (chosen by user) is EX=[0,1,2] and number of terms (m) (excluding bias) is 4, and the number of independent variables (k) is 3, then the polynomial regression problem is to find a matrix of exponents ES 4-3 [15]. An example of such a matrix is given here Each exponent in ES corresponds to a value from the user-defined vector EX. Also, each row of ES determines the exponents of the candidate variables of jth term in equations (2). By implementing the above values in equation (4), the following set of expressions is obtained: Therefore, based on the matrix given in equation (5), the expression of equation (2) is given as: In the next stage, the adjustable parameters, aj, can now be computed, by means of the linear Least Squares (LS) method. The original EPR methodology was based on Single-objective Genetic Algorithm (SOGA) for explore the space of solutions while penalizing complex model structures using some penalization strategies. In this method, in the first stage, the maximum value for the number of terms (m) is assumed then a consecutive search for the formulas having 1 to m terms is undertaken. To accelerate convergence, the results obtained in each stage of search could be randomly entered into the population of the next stage search [15]. However the single-objective EPR methodology showed some drawbacks, and therefore the multi-objective genetic algorithm (MOGA) strategy has been added to EPR. In 2006, Guistolisi and Savic (2006) improved the EPR technique to overcome these shortcomings, using Multi-Objective Generic Algorithm (MOGA) instead of SOGA. The main features of the developed method are as follows [22]: 1) Increasing the model accuracy, 2) Reducing the number of polynomial coefficients, 3) Minimization of the number of inputs (e.g. the number of times each Xi appears in the model). In the developed version, a simultaneous search is conducted for polynomials having 1 to m coefficients; consequently, it is faster than the previous version (i.e., SOGA). In order to determine all models corresponding to the optimal trade-off between structural complexity and fitness level of the model, The EPR technique is Equipped with a range of objective functions which help to optimize the result based on Pareto dominance criterion. The objective functions used are: (i) Maximization of the fitness; (ii) Minimization of the total number of inputs selected by the modeling strategy; (iii) Minimization of the length of the model expression. The objective functions mentioned above can be used in a two objective configuration or all together. In which one of them will limit the complexity of the models, while at least one objective function controls the fitness of the models. In this study the multi-objective EPR is used to develop the EPR-based models. The coefficient of determination (COD) which is used to evaluated the level of models accuracy at each stage is Where Ya is the actual measured output value; Yp is the EPR-predicted value, and N is the number of data points in which the COD is computed.

Cause and Effect on World War 1

Cause and Effect on World War 1 World War One, a huge conflict that sparked in 1914 and lasting all the way until 1918. The war was between the world’s greatest powers as two opposing sides; the Central Powers and the Allies. It was a chain of events that had started this was which consist of key features such as imperialism, alliances, growth of militarism, crisis, and nationalism. It was the result of these accumulating factors that had eventually evoked war. The effects on World War One included over 8 million deaths, higher taxes, rationing of food, and etc.Imperialist is considered a primary cause of war. With Europe’s growing economy and wealth, rivalries and competition for colonies among European nations were more accepted which ultimately led to unrest. Before the war, Europe was growing prosperity and peace. By 1900’s European powers were in control of most African, Asian, and other continents, showing strong ideas of imperialism. While imperialism show cased European strength it also revealed its dependency. Each country’s prosperity hinged on its ability to maintain and expand its colonial empire.This has created competition among imperialist powers for foreign territory. The British felt endangered by Germany’s fast economic growth. Quickly after that, Germany’s new modern factories largely out produced Britain’s older ones. This was a strong economic reason for Britain to oppose Germany in any disagreement. Territiorial disputes was also an ongoing problem with European countries as the leasders wanted more land and didn’t know who owned land was being taken all the times. Imperialism also divided European nations.Now on to the causes that made a difference or that was important with WW1. What exactly were the causes of World War 1? Sounds like a simple straight to the point question, but it’s definitely not. It was more to what think was the whole cause of World War 1, more than the st art of the war than an Austrian prince being murdered in Serbia. Causes of the war also dealt with nationalism, imperialism, and militarism along with the alliance systems in Europe all strongly affected the outbreak of the war. All of these factors where established in many of Europe’s â€Å"Great Powers† which consisted ofGreat Britain, France, Germany, Austria-Hungary, and Russia. The main cause focused on what I stated above, in the previous sentences. The causes of World War 1 include a growing sense of militarism, which was accompanied by arms race, and imperialism. Imperialism as economic rivalries and competition for colonies among European nations were prevalent. What were the effects on World War 1? This war had a few effects on America society, though the war instigated problems, causing n effect that is negative on the American home front. Americans experienced a lot of problems, like the narrowing of our rights and the war caused a patriotic sense to Ameri ca that got to the point where people were discriminating people from other backgrounds. † Also, from many soldiers drafted to war more job opportunities were available. Though this seemed like a good thing, negative effects came out of it The war itself left an everlasting impact. After this was women were gaining more rights. They were gaining rights such as voting and sexual equality.The male dominance patriarchal ideas weren’t so strong anymore. The United States entered the war with the mindset of being neutral and isolated. Russia left the war allowing them to deal with the conflicts. The effects of the war included over 8. 5 million deaths, rationing of food and other products, higher taxes, famine, and propaganda war. This war cost billions of dollars and tons of lives. It brought Japan up to Great Power status, which fueled their ambitions in the Far East. It reinforced the American strain of isolationism which led to the Great Depression. War reparations and t he harsh peace settlement on Germany made conditions ripe to bring Hitler and the Nazis to power, and the war was the straw that broke the back of the Russian monarchy which allowed the Russian Communists to take power (europeanhistory). † The economic and political effects were so great that World War 1 marks the start of a modern era. With all the effects that took place with World War 1, it then started a new war that lead to World War 2, â€Å"The Cold War. † Works Cited Nash, Gary B. , Julie Roy. Jeffrey, and Allen Yarnell. The American People: Creating a Nation and a Society. New York: Harper & Row, 1986. Print.

Fraud, Deceptions, and Downright Lies About Ancient History Argumentative Essay Topics Exposed

Fraud, Deceptions, and Downright Lies About Ancient History Argumentative Essay Topics Exposed A description for this outcome isn't available due to this website's robotstxt learn more. We wish to make certain that the cash you spend on the European history essay topics, by way of example, is well worth the quality you expect. You may use different examples that can be found on the world wide web free of charge. The subject for discussion needs to be manageable, i.e. you ought to be in a position to talk about this issue in the most detailed way based on the quantity of pages you need to write. Professional writers just want to use the ideal research materials for their work. In any case, you might not have a dependable supply of income for a student. College is for a high amount of study. You are able to concentrate on any part of your essay that you want to do first like the conclusion or the introduction. You will incorporate discussion points under each section, which will allow you to write your paragraphs. Your outline will have sections that compose the whole essay. The outline is fundamentally the skeleton for your essay. In addition, the points you communicate has to be factual. At the base of this page, you'll discover some wonderful examples of American history argumentative essay topics for you to pick from, and every one of them will be interesting and fascinating to find out more about. The subjects listed on this page are somewhat universal and might not get the job done so great if you need to produce a flawless history essay. As we begin to think about that idea, here are a number of suggestions to get you started on your own essay. In that case, here's a brief answer. Before you start to compose your essay, you will have to find out more about the thesis statement is an argument overview of the. When it has to do with writing an argumentative essay, the most essential matter to do is to select a topic and an argument you can really get behind. When reading through such materials, it's important to take note of the main points which you would utilize to support your argument. It's thus important to remind the readers of your central argument and offer an overview of the principal points. Besides, you're permitted to communicate directly with the writer handling your paper so you can make any clarifications. Typically, it doesn't include references and quotes in it. Bear in mind, if you're writing an argument about whether they really existed, you are going to want to present evidence to strengthen your argument but will also will need to deal with the counterargument. The quantity and degree of argument aren't extreme. Argue aspect which resulted in the holocaust. Analyze the historical importance of the number 13. The 5-Minute Rule for Ancient History Argumentative Essay Topics There are lots of aspects about a sport which can be argued in an essay. Our experts understand how to handle US history essay topics with a bit of class. Do not increase your odds of being discontinued from your studies as a result of trusting people who cannot even aid with choosing history essay topics for high school students. The intent of assigning an essay to middle school students is to make awareness and permit them to develop writing skills. The War Against Ancient History Argumentative Essay Topics What's the Iron Lady's role on earth history. Keeping that in mind, it is simpler to understand the nation's cultural diversity and complexity of its history. Argue the effect of newspaper in politics. Furthermore, their effect on the culture and history of America. Ancient History Argumentative Essay Topics for Dummies Moreover, in-text citations will present your awareness of the various papers formats. To begin with, the paper is passed through Copyscape application to make sure that it's not plagiarized. However, in case it fails to meet your requirements, you are allowed to request a refund. Or i t might focus on medical discoveries, such as the polio vaccine or penicillin. Key Pieces of Ancient History Argumentative Essay Topics While you might not get the possibility of attempting all of them, select the field which interests you, choose any topic and begin writing. In any case, it has to attract your readers' attention, and thus it ought to be brief and right to the point. You must be quite sure in regards to the notion which you want to expand on. Argue not all sportsmen can get fantastic coaches. Top Ancient History Argumentative Essay Topics Secrets If you wish to compose the essay yourself, we believe it would be best to select a universal subject or issue. The topic ought to be quite controversial once you are writing an argumentative write up. Thus, it should be debatable! It is the most important thing for an essay. Due to this, many disagree on the way the laws should change (if they ought to change at all) and there are numerous topics to select from. So make sure you select a subject, which has values in it. Let us take a look at some of the internet topics on the argumentative essay at various degrees of education. It's possible to go for an intriguing topic from any area of science.

Probability and Distributions in Qualitative Analysis

Probability and Distributions Quantitative analysis can be a very complex undertaking, but a little understanding can go a long way. Before any statistical analysis or in-depth investigation of quantitative data is attempted, one should at least build an understanding of some of the basic elements of probability. The following paragraphs provide a definition and explanation of the two basic laws of probability and an examination of two types of probability distributions, and while this will not allow for truly meaningful quantitative analysis to take place it will provide a foundational understanding that anyone can utilize to begin investigating probability and statistics. The two basic laws of probability are, as their basic nature implies, relatively simple to understand, despite the fact that they might not seem simple or easily approachable when concisely stated. The first rule is that the probability of any event must be between zero and one, inclusive, and the second (and very highly related) rule is that the sum of the probability of all events must equal one. Though this might seem foreign to one not used to dealing with numbers, it is actually quite simple, and it is from these two basic laws that simple probabilities (and thence more complex probabilities) can be established. Take the flip of a coin as an example: there are two possible outcomes, each of which must have a probability between zero and one and the sum of which must be equal to one. If there isShow MoreRelatedRisk Control Techniques, Limitations And Challenges1052 Words   |  5 Pageswith uncertainties, which always indicate a potential loss. Therefore, risk analysis and management have played an increasingly important role in business decisions. As the demands arise, risk analysis techniques are gradually improving and perfecting. 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Form a histogram, frequency polygon and frequency curve of the frequency distribution (from part a) Ques.3 Compute the mean, standard deviation and Coefficient of variation of the following data and comment on the result Size 12.5 13Read MoreEvaluation Of A New Product Development1021 Words   |  5 PagesManagement Techniques Each likely and unlikely event has its own probability of occurrence. Risk is a measure of probability of occurrence of an unlikely event. Early in design phase the amount of uncertainty is high for all events. Assuming those uncertainties in the beginning of the design phase will help mitigate risks or even avoid those risks throughout the development of the product [11]. Ways of analysing risks: 1. Quantitative Analysis: Find factors affecting the process. Assign costs to each

Functionalism Of A Right Hand World - 876 Words

Ten to fifteen percent of people are left-handed. I myself am included in that ten to fifteen percent, along with my mother and brother. The world is made up mainly of right-handed people that cause left handed handshakes to be weird and using the mouse with our left hand unusual. Forget that left-handed humans are normal; I have to learn how to adjust to this functionalism of a â€Å" right hand world†. Most appliances are made to fit the comfort of right handed people, including the computer mouse, the gear shifter in a vehicle, even a pair of scissors. Talk about some counterculture moments I had to experience. Even the social normality gesture of the handshake shows right-handed dominance. Us lefties are forced to adjust to a favored right hand society. I have to accommodate and be okay with learning how to be comfortable with both hands. Being a left-handed person can often be referred to as a Structural-functionalist in the eyes of a Sociologist. 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Holoprosencephaly its nature and manifestation Free Essays

our site – CUSTOM ESSAY WRITING – HEALTH DISSERTATION TOPICS Abstract An exploration into Holoprosencephaly, the genetic birth defect; we will observe how it presents itself in su erers- the physical and neurological symptoms, we will brie y try to identify the main candidates that can be linked to its etiology and nally taking the SHH pathway as an example we will explain how a genetic mutation could give rise to the associated symptoms of HPE. 1 HPE Holoprosencephaly (HPE) is a congenital defect in the nervous system, whereby the developing prosencephalon (or forebrain) fails to bifurcate into left and right hemispheres- typically occurring ve to six weeks into pregnancy (Golden, 1999). It is the most common malformation of the brain- occurring in 1:250 developing embyros, with 1:8,000 live births due to a 3% chance of survival to delivery (Co-hen, 1989). We will write a custom essay sample on Holoprosencephaly: its nature and manifestation or any similar topic only for you Order Now The failure of the cleavage into two bilateral cerebral hemispheres gives rise to a continuum of motor and developmental malformations, the most prominent being craniofacial defects and damaged brain structure. There are four classes of HPE1, varying in the degree of cortical separation and associated severity of symptoms2 (Raam, 2011). The most severe form is Alobar HPE, this is characterised by a complete or near lack of interhemispheric separation and an absence of olfactory bulbs and corpus callosum. This makes up roughly two-thirds of HPE patients (OMIM, 2012), the most extreme grade in this class will have cyclopia: no separation along the midline of the brain, with no sense of chirality in their embryogenesis. In this case the foetus will develop a single, medial eye above the root of the nose- they will rarely survive the perinatal period. The next class is Semilobar HPE, which can be identi ed by a partial posterior cortical separation (but no anterior) with basal hemispher es, the olfac-tory bulbs and corpus callosum are either absent or hypoplastic. In this case the eyes are now slightly separated by proboscis, but the motor skills are still highly impaired. The next form is lobar HPE, this is a milder form of semilobar, di er-entiated by the latter by the presence of a frontal horn in the lateral ventricle. Lobar has an interhemispherical ssure, but there still incomplete separation of the prosencephalon; the corpus callosum is absent in the a ected region and the olfactory bulbs are hypoplastic. There is less severe motor malfunction, and the face can develop closely spaced eyes, at nose and cleft lip. The fourth and mildest form is the Middle Interhemispheric Variant (MIV), where the most a ected regions of nonseparation occur in the posterior frontal and pariental lobes; the corpus callosum is typically absent in the region or hypoplastic. This variant of HPE has mild craniofacial and neurological impairments. All of these deformities can be dete cted through neuroimaging, and can be discerned by the above phenotypes. 2 Causes Current research into the causes of HPE is still developing; most sources can-not give exact causes, but there a number of factors that have been linked to the disorder. The most supported model is given by the Multiple Hit Hypothesis which states that HPE derives from a combination of environmental and genetic factors, i.e. it is an autosomal-dominant disease; it is believed that this would explain the heterogeneity of the phenotypes (OMIM, 2012). Teratogens are be-lieved to disturb the development of the normal phenotype: maternal diabetes has been linked to a 200% increased risk of HPE in the foetus( Croen, 2000; Raam, 2011). This along with hypocholesterolemia and the drug cyclopamine are linked to disturbances in cholesterol production, inhibiting the Sonic Hedge-hog (SHH) Signalling Pathway (Cohen, 1989). The fact that the defects occur early in pregnancy implies a gastrulation disorder supporting the theory that infections whilst pregnant and drug taking (alcohol, anti-epilept ic medication 1 There is a mild associated form called Microform, with similar craniofacial characteristics, but no sign of nonseparation, as such typically not considered within HPE. 2 A common used term is that â€Å"the face predicts the brain†, this is a general correlation that exists between the degree of mental and physical retardation and mortality within the four classes and ethanol for example) are likely environmental causes. The genetic etiology are related to familial occurrences3, genetic syndromes of HPE and non ran-dom chromosomal aberrations- identi ed by high resolution karotype counts, or DNA microarrays. A relatively common cause of HPE-approximately 28%, (Geng, 2009)- has been found to be loss-of-function mutations in the genes: SHH, ZIC2, SIX3 and TGIF- whereby the particular gene product will be un-able to perform its original function. There are ve other genes identi ed with HPE, but these four mutations are the most prevalent and as such are the main roots for DNA sequencing. These genes are related to the Nodal and SHH pathways. De ciency in the Nodal protein results in a failure to form the PrCP gene; this e ects the formation of the primitive streak. The establishment of this structure is important in creating a longitudinal plane of symmetry along the embryonic disk that allows cell migration into the midline to create the mesoderm, the cells of which form a rod called the notochord. The SHH gene is a morphogen that regulates ventral midline structure in the forebrain (Roessler, 2003) and is crucial in formation of the eyes and face. It is a molecule that responds to variations in a concentration gradient within the neural tube by di using Sonic Hedgehog, produced by the signalling centre of the notochord (Placzek, 1999). 3 How the gene leads to the disorder In order to understand how HPE4 manifests itself through the mutation in this gene we will consider its role in brain embryology (Marieb, 2003). By around the fth day after fertilisation, the blastocyst of the egg is released- this is a sphere composed of trophoblast cells and inner cell mass; this will undergo gastrulation whereby the inner cell mass is converted into the three primary germ layers and the embryonic disk. This disk attens and a primitive streak creates a midline depression along the median. Three weeks into pregnancy the ectoderm thick-ens along the dorsal midline axis of the embryo to form the neural plate, which when folds into the neural tube by the fourth week, the anterior of which expands rapidly to form the three brain ventricles of the prosencephalon along with the middle and the hindbrain; by this time eye rudiments are present. Normally, in the fth week the prosencephalon will bifurcate into the diencephalon and the telencephalon-from the dorsal plate and v entral plate, respectively- connected by the corpus callosum. The telencephalon then â€Å"swells† into the cerebral hemi-spheres and by the eighth week all brain exures are formed. The role of the SHH gene is to produce the Sonic Hedgehog protein that signals the activation of the ventral midline of the forebrain. In HPE, with a mutated SHH gene, there is a reduced or no production of this protein and as a result the fore-brain will not split into a left and right (Roessler, 2003). Along with this it secretes the molecule responsible for signalling the division of a single eye eld 3 There are a number of case studies in (OMIM, 2012) on families where HPE is an inherited condition 4 To be exact, this is Holoprosencephaly type 3 into two distinct eyes. Hence, a SHH mutation can lead to a lack of interhemi-spheric separation and merging of the eyes, which would a ect the development of the rest of the face. This shows the symptoms of HPE su erers, suggesting the disorder is a subclass related to the loss-of-function of the SHH signalling pathway. If there was a complete lack of SHH signalling there would be no separation in the telenchephalon, and as such no connecting corpus callosum, the primordial eye eld would not divide into two lateral eye elds, thereby resulting in an embyro with cyclopia from Alobar HPE. Similarly, inactivity of the Nodal signalling pathway causes failure in the formation of the mesendo-derm and axis-asymmetry. As stated before there are a number of genes that are linked to HPE that also regulate organogenesis but the spectrum of the disorder is entirely variable and there are 75% of HPE cases that do not have any of these gene mutations . The most satisfactory hypothesis is the Multi-hit model; there is no single exact cause that could trigger the defect in all of the presented cases and produce the four classes of severity, but it is possible that the pathogenesis must involve some event in the regulatory regions that induces the expression of the four identi ed genes in the forebrain, though the trigger might not necessarily be the same in every instance. 4 References Cohen, M.M. Jr., Perspectives on holoprosencephaly: Part III. Spectra, distinc-tions, continuities, and discontinuities. Am J Med Genet. 1989; 34: 271-88. Cohen, M Shiota, K, Teratogenesis of Holoprosencephaly. Amercian Journal of Medical Genetics. 2002; 109: 1-15. Croen L.A, Shaw G.M Lammer E.J, Risk factors for cytogenetically normal holoprosencephaly in California: A population-based case-control study. Am J Med Genet. 2000; 90: 320-325. Geng, X Oliver, G, Pathogenesis of holoprosencephaly. J Clin Invest. 2009;119(6):14031413 Golden, J.A, Towards a greater understanding of the pathogeneis of holoprosen- cephaly. Brain Dev. 1999; 21: 513-521. Graham, J.M. Jr. Shaw, G.M, Gene-Environment Interactions in Rare Dis-eases that Include Common Birth Defects. Birth Defects Research. 2005; 73: 865-867. Marieb, E.N, Human Anatomy and Physiology. California: Benjamin Cum-mings, 1989. Online Mendelian Inheritance in Man, OMIM. Johns Hopkins University, Bal-timore, MD. MIM Number: 236100. [Accessed 28/11/2012] World Wide Web URL: http://omim.org/ Placzek, M, The role of the notochord andoor plate in inductive interactions. Genetics and Development. 1997; 5(4): 499-506. Raam, M.S, Soloman, B.D Muenke, M, Holoprosencephaly: A Guide to Di-agnosis and Clinical Management. Indian Pediatrics. 2011; 48: 457-466. Roessler, E Muenke, M, How a Hedgehog might see holoprosencephaly. Hu-man Molecular Genetics. 2003; 12(1): R15-R25. How to cite Holoprosencephaly: its nature and manifestation, Essay examples

Analysis of the Arts Mona Lisa Essay Example For Students

Analysis of the Arts Mona Lisa Essay The Mona Lisa is one of the few paintings that have seen in person. Dont know Why she is so intriguing to look at but something about her smile and her eyes captivate me. The realness of the painting and how ordinary the Mona Lisa is the reason Why I can kick at this painting With great joy, it doesnt make me think too much, it doesnt confuse me, the simplicity and the normalcy of this painting is what I enjoy so much. However, after an analysis you can see that the painting isnt so ordinary. The painting is done by using a liquid media. The Leonardo De Vinci used oils to ant his picture. During the 15th century using oils was very common. By using oils Leonardo was able to create a real lifelike painting, since the oils dry slowly he was probably able to mix and rework all his colors and shading until they were just the right hue and looked perfect. In this painting there is no distinct line, There is a lot of shading giving the figure shape and gives outlines other the clothing becomes a hand or where the forehead becomes hair. However, it is just like a photograph, you can see where the chin stops and the neck begins. However, the lines are subtle and not over exaggerated. You can see however, that the painting seems to be made up of three triangles. Mona Lisa being the biggest they the left top corner is the background and the top right corner are a continuation of the background However, these two backgrounds seem to not be part of the same landscape. When you look at the form of the work it is clear that the picture is non- objective, it is obvious that the painting is of a woman. However, what is objective about the woman is her facial expression, What is she looking at, is she even looking at anything, who is the woman, is she or isnt she smiling, if she is smiling What at, and so on and so on. Leonardo use Of form in the painting is What makes the Mona Lisa so intriguing to look at you can make up any story youd like and no one can tell you youre wrong. Leonardo originally used more somber colors; there is not outstanding, unrealistic color that pops out. Everything about the color, from the sleeves of the dress to her lips makes the picture realistic, He uses just the right amount of darker colors to make realistic shading. The top half of the painting has a very higher value of color, the colors are lighter and more airy while the bottom half of the painting has a lower value of color, the colors are darker and more shaded. There is a certain balance about the photo as well; everything is split right down the center starting at her hair line, going down the face, proceeding right to where the hands cross. The background is on the left and the right. Since the foreground is so busy and beautiful the background seems to be faded and not have distinct features and detail Over all the focal area is naturally the Mona Aliass bright face which is in the middle of the painting. The Mona Lisa seems to pop out of the picture; you can tell that there is a sense of depth because of the viva she is angled on the chair, s well as in the background. It is beautifully done I love this painting, I dont know if it is because have seen it in person, or how beautiful it is even though it is simplistic. It captures a normalcy Which is intriguing but a beauty like no other. It makes me think of what beauty was back then and What beauty is now today. You would never see someone With her looks is painted and the picture would become a masterpiece. I also like the smile and the eyes, they go perfectly together to make a subtle expression that is hard to capture in photographs even today! In my mind it is the perfect balance of all elements.