What is the relationship between mean and standard deviation?

Mean and standard deviation are important indexes reflecting data distribution in statistics
Mean: a measure of the trend in a dataset. Its typical formula is:
Mean a = (x1 + x2 + X3 +. + xn) / n
Standard deviation: a measure that represents the trend of data dispersion. Its typical formula is as follows:

RELATED INFORMATIONS

1. What are mean, standard deviation and relative number?
2. Who knows how to find P with mean standard deviation n
3. Who knows how to write and read the sign of "weighted average"! Is it X or x?
4. Semiotics ~ all
5. How to pronounce the sign of average
6. How to read the density symbol ρ
7. Add, subtract and multiply between 12345678 octets to make it equal to 1
8. How can 123456 be equal to 7 by addition and subtraction
9. How can 123456789 be equal to 100 only by addition and subtraction?
10. Add a sign before 12345678 to make his result negative 4
11. Who can help me calculate the mean ± SD Group 1: age: 21,22,27,28,16,16,15,16,15,15,16,16,17,17,12,10,16,4,15,19,16,61,4,14,14,9,5,2,9,4,55,14,38,11,3,3,10,32,22,22,33,23,27,21,15,5,38,37,6,22,31,35,52,25,14,20,17,14,14,16,52,5,35,16,32,28,15 The second group: days: 10,9,2,7,9,9,9,10,6,10,5,9,8,7,5,6,4,5,7,10,6,4,4,6,5,12,10,4,10,5,4,3,4,3,7,5,5,6,9,6,5,4,7,13,3,12,5,7,4,5,7,6,8,9,6 The third group: days: 51 cases, the incubation period, the first day 27, the second day 10, the third day 6, the fourth day 7, the fifth day 1, the average incubation period of how many days? Group 4: days, 65 samples, 1 case turned negative on the first day, 7 on the second day, 30 on the third day, 17 on the fourth day, 6 on the fifth day, 4 on the sixth day, how many days turned negative on average
12. How to read? What symbols? It's like an eight
13. How to read the sign of standard deviation is not Sigma in the quantitative method,
14. We have already calculated the standard deviation of mean addition and subtraction. How can we compare it with the national norm in SPSS and calculate t
15. I have a group of data of mean plus minus standard deviation. I want to compare between groups and calculate p value. Who can tell me how to do it with SPSS software? Must statistics software how to do ah, because I have several groups, have to calculate ah Group quantity data C 12 0.983+0.062 M 12 0.735+0.059 HD 12 0.927+0.084 MD 12 0.911+0.065 LD 12 0.916+0.045 X 12 0.937+0.038
16. What is the standard deviation of the mean?
17. What does lognormal distribution use to describe concentration and dispersion, geometric mean plus minus standard deviation? Mean and standard deviation (sometimes variance) should be used to describe the concentration and dispersion of normal distribution data, which is recorded as X ± S. median and interquartile spacing, mean deviation, etc. should be used to describe skew distribution data. What is the representation of lognormal distribution after variable transformation in the article, and what is the procedure in SPSS,
18. What is the mean plus minus standard deviation In a group of mathematical statistics, it is found that a parameter is not well understood, that is, the mean ± standard deviation of a group of numbers What is the meaning of this in mathematical statistics? My statistics are as follows: The first group of data: (24 25 26) mean: A for standard deviation, B for standard deviation Then I calculate a with a fixed formula to get a value a But later, the software uses a + B to get a + through the above formula, and A-B gets a - What is the significance of this in mathematical statistics?
19. How to make the standard deviation format of mean addition and subtraction by SPSS
20. Would you please fill in the operation symbols in brackets with 0.25 () 0.25 () 0.25 () 0.25 = 0.125