我有一个关于人们购买特定产品(比如说肥皂)的交易数据,我想了解购买肥皂的强度是如何随时间变化的。我将强度定义为一天中使用的肥皂的平均数量,假设一个人再次购买时,他/她完成了之前供应的肥皂。此外,还需要对每个消费者的异常值进行delate(消费者的平均个人数+-2*消费者的标准差个人数),并对上次购买后的信息进行delate
目前,数据帧如下所示:
transacrions <- data.frame(Client_ID = c(1, 2, 1, 3, 4, 1, 3, 2, 1),
date = c("2017-01-01", "2017-01-01", "2017-01-02", "2017-01-03", "2017-01-04", "2017-01-05", "2017-01-06", "2017-01-09", "2017-01-10"),
soaps_bought = c(1, 12, 2, 19, 20, 10, 32, 12, 11))
partial_results <- data.frame(Client_ID = rep(1:4, each = 10),
date = rep(seq(as.Date("2017-01-01"), as.Date("2017-01-10"), by = "day"), 4),
soaps_bought = c(1, 2, NA, NA, 10, NA, NA, NA, NA, 11,
12, NA, NA, NA, NA, NA, NA, NA, 12, NA,
NA, NA, 19, NA, NA, 32, NA, NA, NA, NA,
NA, NA, NA, 20, NA, NA, NA, NA, NA, NA ))
第二步将计算购买之间经过的天数,并计算平均使用量。最好也详细介绍一下上次购买的情况:
partial_results_II <- data.frame(Client_ID = rep(1:4, each = 10),
date = rep(seq(as.Date("2017-01-01"), as.Date("2017-01-10"), by = "day"), 4),
avg_soaps_bought = c(1/1, 2/3, 2/3, 2/3, 10/5, 10/5, 10/5, 10/5, 10/5, 11/1,
12/8, 12/8, 12/8, 12/8, 12/8, 12/8, 12/8, 12/8, 12/2, 12/2,
NA, NA, 19/3, 19/3, 19/3, 32/5, 32/5, 32/5, 32/5, 32/5,
NA, NA, NA, 20/7, 20/7, 20/7, 20/7, 20/7, 20/7, 20/7 ))
desired_results <- dcast(setDT(partial_results_II), Client_ID ~ date, value.var = "avg_soaps_bought")
我计算了每个人的平均值和标准差,甚至检查了哪些是异常值,但我现在不知道如何根据这些数据来挖掘观察结果
desired_results_DF <- data.frame(desired_results)
avg <- rowMeans(desired_results_DF[, -1], na.rm = TRUE)
library(matrixStats)
desired_results_MX <- data.matrix(desired_results_DF[, -1])
sd <- rowSds(desired_results_MX, na.rm = TRUE)
is_ok <- desired_results_DF[, -1] < avg + 2 * sd | desired_results_DF[, -1] > avg - 2 * sd