在gmat數學的備考過程中，對基本數學概念的理解和記憶很重要，在gmat考試的過程中，會出項一些關于gmat數學統計的問題，下面就是關注這些題目的一些常見統計概念，供大家參考。

　　gmat數學備考之描述統計

　　1.平均數

　　2.中數

　　To calculate the median of n numbers，first order the numbers from least to greatest;if n is odd，the median is defined as the middle number，while if n is even，the median is defined as the average of the two middle numbers. For the data 6, 4, 7, 10, 4, the numbers, in order, are 4, 4, 6, 7, 10, and the median is 6, the middle number. For the numbers 4, 6, 6, 8, 9, 12, the median is /2 = 7. Note that the mean of these numbers is 7.5.

　　3.眾數：一組數中的眾數是指出現頻率最高的數。

　　例：the mode of 7，9，6，7，2，1 is 7。

　　4.值域：表明數的分布的量，其被定義為最大值減最小值的差。

　　例：the range of1，7，27，27，36 is 36-= 37。

　　5.標準方差：

　　One of the most common measures of dispersion is the standard deviation. Generally speaking, the greater the data are spread away from the mean, the greater the standard deviation. The standard deviation of n numbers can be calculated as follows:

　　find the arithmetic mean ;

　　find the differences between the mean and each of the n numbers ;

　　square each of the differences ;

　　find the average of the squared differences ;

　　take the nonnegative square root of this average.

　　Notice that the standard deviation depends on every data value, although it depends most on values that are farthest from the mean. This is why a distribution with data grouped closely around the mean will have a smaller standard deviation than data spread far from the mean.

　　GMAT數學的基本概念，如果考生加以歸類，會感覺沒有想象中那么復雜和混亂。考生可以根據歸類的GMAT數學基本概念，加以復習和記憶。還要提醒考生的是，GMAT數學的基本概念，最忌諱的是死記硬背，考生最好采用理解式記憶法，GMAT數學基本概念就能輕松搞定。

　　通過上面對gmat數學基本概念中的統計概念的介紹，相信對于很多計劃參加gmat考試的人來說，可以參考上述的信息來做好gmat數學考試的備考和準備工作。

　　在gmat數學的備考過程中，對基本數學概念的理解和記憶很重要，在gmat考試的過程中，會出項一些關于gmat數學統計的問題，下面就是關注這些題目的一些常見統計概念，供大家參考。

　　gmat數學備考之描述統計

　　1.平均數

　　2.中數

　　To calculate the median of n numbers，first order the numbers from least to greatest;if n is odd，the median is defined as the middle number，while if n is even，the median is defined as the average of the two middle numbers. For the data 6, 4, 7, 10, 4, the numbers, in order, are 4, 4, 6, 7, 10, and the median is 6, the middle number. For the numbers 4, 6, 6, 8, 9, 12, the median is /2 = 7. Note that the mean of these numbers is 7.5.

　　3.眾數：一組數中的眾數是指出現頻率最高的數。

　　例：the mode of 7，9，6，7，2，1 is 7。

　　4.值域：表明數的分布的量，其被定義為最大值減最小值的差。

　　例：the range of1，7，27，27，36 is 36-= 37。

　　5.標準方差：

　　One of the most common measures of dispersion is the standard deviation. Generally speaking, the greater the data are spread away from the mean, the greater the standard deviation. The standard deviation of n numbers can be calculated as follows:

　　find the arithmetic mean ;

　　find the differences between the mean and each of the n numbers ;

　　square each of the differences ;

　　find the average of the squared differences ;

　　take the nonnegative square root of this average.

　　Notice that the standard deviation depends on every data value, although it depends most on values that are farthest from the mean. This is why a distribution with data grouped closely around the mean will have a smaller standard deviation than data spread far from the mean.

　　GMAT數學的基本概念，如果考生加以歸類，會感覺沒有想象中那么復雜和混亂。考生可以根據歸類的GMAT數學基本概念，加以復習和記憶。還要提醒考生的是，GMAT數學的基本概念，最忌諱的是死記硬背，考生最好采用理解式記憶法，GMAT數學基本概念就能輕松搞定。

　　通過上面對gmat數學基本概念中的統計概念的介紹，相信對于很多計劃參加gmat考試的人來說，可以參考上述的信息來做好gmat數學考試的備考和準備工作。