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[求助]
R求助
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最近用R处理数据，有以下几个问题问高手: 1,You used a linear model. This assumes that your data (the residuals) are normally distributed? If not, have you tried to transform the residuals so that they are normally distributed? If residuals are not normally distributed and cannot be transformed so that they become normally distributed, have you tried a generalized linear model (GLM) with an appropriate error structure (given by the "family"-command in glm - in R: model <- glm (y ~ x), family= "gaussian / binomial / Gamma / etc."  对于统计数据中有缺失的部分，我一律用R代替，请问如何判断这些数值的出现是否为"gaussian / binomial / Gamma ？还是要一个一个尝试？ gaussian / binomial / Gamma 怎么体现在R语句中？具体怎么操作？ 2, What y and what x did you use in "lm(formula = y ~ x)"? You can use several explanatory variables (x) in a lm or glm but only one response variable (y)? 3,With the ratio of annual species and perennial species, I suggest that you use the logarithm of this ratio: log (annuals / perennials) - this is usually done with ratio-data 对于较小的数值（0—1之间），一般取log，请问是取什么为底的函数？10，2， 还是e? 谢谢！ |
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2楼2013-11-01 13:44:25
