【正文】 the use of bank cards will be greatly decreased. Then the total revenue of bank card decrease. If the price is lower, the issuing and trading volume increased will do more significant to total revenue increase. (2) indicates that bank card products or services lack of price elasticity of demand. The change of demand was less than changes in prices. Then at lower prices will lead to a decrease in total ine. (3) indicates that bank card product or service demand price elasticity is unit. Changes in price changes and the demand is the offset. Results the total revenue do not change.Determinants of bank card price elasticity of demand of a product or service as follows:First, the importance of bank card products and services to consumers. With the popularization of bank card, it bees the main settlement tools and meet people convenience, security needs and consumer demand. Bank card general service function is to meet the needs of payment and settlement with a small demand elasticity. However, the added value and function of the product have a great price elasticity. Local card price elasticity of demand is different from crossborder Khaki bank card. Second, bank card products or services substitutability. The more alternatives for a modity the more powerful alternative. Therefore, the more the substitution of bank card products or services the stronger the degree of substitution. Then the price elasticity of demand will be relatively large. Increasing the price will lead the consumers purchase the other substitutes such as online bank.價格對銀行卡消費需求的影響銀行卡產(chǎn)品或服務需求的價格彈性是衡量銀行卡產(chǎn)品或服務的需求量對于價格變化的反應程度的尺度,是銀行卡產(chǎn)品或服務需求量變化的比率與價格變化的比率之間的比值,其需求價格彈性公式為：式中，代表銀行卡產(chǎn)品和服務的需求的價格彈性系數(shù)，代表銀行卡產(chǎn)品或服務的價格，代表銀行卡產(chǎn)品或服務的價格變動，代表銀行卡產(chǎn)品或服務的需求量，代表銀行卡產(chǎn)品或服務的需求的相應變動量。需求朝著與價格變動相反的方向變動，因此，銀行卡產(chǎn)品或服務的需求價格彈性一般是負值，實際運用只取其絕對值。銀行卡產(chǎn)品或服務的需求價格彈性將需求的變化和價格變化聯(lián)系起來了分析如下：(1) ，表明銀行卡產(chǎn)品或服務的需求富有價格彈性，需求量變動的幅度大于價格變動的幅度。若價格提高，銀行卡的使用會更大幅度地下降，會造成銀行卡總收益減少；若價格降低，發(fā)卡量及交易量更大幅度的增加會使總收益增加。(2) ，表明銀行卡產(chǎn)品或服務的需求缺乏價格彈性，需求量變動的幅度小于價格的變動幅度。(3) ，結果使總收益不變。銀行卡產(chǎn)品或服務需求價格彈性的決定因素：（1）銀行卡產(chǎn)品和服務對消費者的重要程度。隨著銀行卡的普及推廣，銀行卡成為人們主要支付結算工具，并滿足人們方便快捷、安全需要、消費需求。銀行卡的一般服務功能是滿足支付結算需要，需求彈性小。而擁有附加值服務功能的產(chǎn)品則價格彈性大，地方卡、跨國界卡其銀行卡的需求價格彈性也是不一樣的。（2）銀行卡產(chǎn)品或服務的可替代程度。某種商品的替代品越多，則該種商品的替代性越強。因此，銀行卡產(chǎn)品或服務的替代品越多，則該種銀行卡產(chǎn)品或服務的替代程度越強，那么它的需求價格彈性就會相對較大。此時，銀行卡產(chǎn)品或服務的價格提高，會引起消費者購買其他替代品。例如網(wǎng)上銀行服務。譯文2 HeteroscedasticityIf the residual standard deviation of a set of estimates of the value of a dependent variable unsteady, then there exists heteroskedasticity. This is contrary to the premise of linear regression models, namely the requirement of all, variances of random errorsare the same. In the other words, effects of random errors are not affected by the variable and observation sequence. Probably because the viewer attention drops, caused measurement error, resulting in a group of random error bees large, then there will be heteroscedasticity.Heteroskedasticity leads to estimate non effective, and the regression coefficient standard errors are biased, thus, confidence interval estimation value is not accurate.To find out the heteroscedasticity, can be as abscissa,as ordinate to draw scatter diagram, intuitive judgment on the residuals. If there is heteroscedasticity, a triangle will appear on the diagram.The most famous test of heteroscedasticity is Goldfeld/Quandt test. The test is the sampling variance of residuals is divided into two parts, such as a time series of the first half and the second half, then contrast. If there is exactly the same variance, then two variances equal, namely the variance of the ratio of two samples is1. The more the ratio deviates from the 1, the less credible of equal variance assumption. If the residual error obeys normal distribution, the establishment of the homoscedasticity assumption, then the variance ratio obeysdistribution and can be used as a test statistic variance with the null hypothesis. The calculation of thetest statistic as follows:. Among themand.Among them, and represents the number of sampling two samples, indicates the number of variables in a regression model. According to to arrange the two samples. Given the significant level, parison of calculated value and the theoreticalvalue of degree of freedom.Another way to find heteroscedasticity is Glesjer method, namely construction of absolute error regression model about the regression equation:About the homoscedasticity, a null there is significant deviation from a factor of 0, declined the homoscedasticity assumption.Treatment of heteroscedasticity, can be tried by the dependent variable transformation or the relationship between transformation, to establish the equal variance of random error term. Nonlinear transform are included in this kind of transformation. Therefore, the heteroscedasticity is mostly belongs to the nonlinear problem, heteroscedasticity test also can be regarded as a nonlinear test.異方差性若因變量的一組估計值中，殘差的標準差非恒定，則存在異方差性。這違背了線性回歸模型的一個前提，即要求對所有的，隨機誤差項的方差都相同，換句話說，隨機誤差項不能受自變量和觀察次序的影響。可能因為觀察者的注意力下降，而造成測量誤差，從而導致一組觀察中的隨機誤差項變大，則此時會出現(xiàn)異方差性。異方差性會導致估計非有效，以及回歸系數(shù)的標準差有偏，由此，置信區(qū)間的估計值變得不準確。要查明異方差性，可以以為橫坐標，為縱坐標繪制散點圖，直觀的對殘差進行判斷。若存在異方差性，圖中大多會出現(xiàn)一個三角形。最著名的異方差性檢驗是Goldfeld/Quandt檢驗，該檢驗是將殘差的抽樣方差分成兩個部分，如一個時間數(shù)列的前半段和后半段，然后再進行對比。若存在完全同方差性，則兩方差一定相等，即兩子樣的方差之比為1。兩者之比越偏離1，方差相等的假設越不可信。若殘差服從正態(tài)分布，同方差性假設成立，則方差比服從分布，可作為同方差零假設的檢驗統(tǒng)計量。檢驗統(tǒng)計量的計算如下：。其中，和其中，和表示兩個子樣的抽樣個數(shù)，表示回歸模型中的自變量個數(shù)。依照編排兩個子樣。給定顯著水平下，比較求出的值與自由度為的理論值。查明異方差性的另一個方法是Glesjer法，即構建殘差絕對值關于回歸自變量的回歸模型：對同方差性，有零假設。若出現(xiàn)顯著偏離0的系數(shù)，則拒絕同方差性假設。處理異方差性，可嘗試通過因變量變換或整個回歸關系式變換，來建立隨機誤差項的同方差性。此類變換大多包含非線性變換，因此，異方差性也大多屬于非線性問題，異方差性檢驗也可視為非線性檢驗。