我需要降低因子变量“武器描述”的级别，该变量有 80 个级别，我希望它为 8。当我希望结果为二进制时，我之前使用过 grepl。现在我需要 8 个级别，我不知道如何继续。下面的例子是如果结果是二元的我将如何处理。我需要帮助将其扩展到 8 种类型。
crime_3yr$Weapon.Used<-ifelse(grepl(crime_3yr$Weapon.Description,pattern = "GUN|AXE|RIFLE"),"Melee","Ranged")
目前，前 10 个级别是:
AIR PISTOL/REVOLVER/RIFLE/BB GUN"
[3] "ANTIQUE FIREARM"
[4] "ASSAULT WEAPON/UZI/AK47/ETC"
[5] "AUTOMATIC WEAPON/SUB-MACHINE GUN"
[6] "AXE"
[7] "BELT FLAILING INSTRUMENT/CHAIN"
[8] "BLACKJACK"
[9] "BLUNT INSTRUMENT"
[10] "BOARD"
[11] "BOMB THREAT"
我希望它是:
hand gun"
[3] "hand gun"
[4] "Assault rifle"
[5] "Assault rifle"
[6] "melee"
[7] "melee"
[8] "melee"
[9] "melee"
[10] "misc"
[11] "misc"
我意识到我还没有提供我想要的 8 个级别，因为我还没有决定最终因素。我只需要知道如何将原来的级别分成2个以上的级别。 80 个级别是
[2] "AIR PISTOL/REVOLVER/RIFLE/BB GUN"
[3] "ANTIQUE FIREARM"
[4] "ASSAULT WEAPON/UZI/AK47/ETC"
[5] "AUTOMATIC WEAPON/SUB-MACHINE GUN"
[6] "AXE"
[7] "BELT FLAILING INSTRUMENT/CHAIN"
[8] "BLACKJACK"
[9] "BLUNT INSTRUMENT"
[10] "BOARD"
[11] "BOMB THREAT"
[12] "BOTTLE"
[13] "BOW AND ARROW"
[14] "BOWIE KNIFE"
[15] "BRASS KNUCKLES"
[16] "CAUSTIC CHEMICAL/POISON"
[17] "CLEAVER"
[18] "CLUB/BAT"
[19] "CONCRETE BLOCK/BRICK"
[20] "DEMAND NOTE"
[21] "DIRK/DAGGER"
[22] "DOG/ANIMAL (SIC ANIMAL ON)"
[23] "EXPLOXIVE DEVICE"
[24] "FIRE"
[25] "FIXED OBJECT"
[26] "FOLDING KNIFE"
[27] "GLASS"
[28] "HAMMER"
[29] "HAND GUN"
[30] "HECKLER & KOCH 91 SEMIAUTOMATIC ASSAULT RIFLE"
[31] "HECKLER & KOCH 93 SEMIAUTOMATIC ASSAULT RIFLE"
[32] "ICE PICK"
[33] "KITCHEN KNIFE"
[34] "KNIFE WITH BLADE 6INCHES OR LESS"
[35] "KNIFE WITH BLADE OVER 6 INCHES IN LENGTH"
[36] "LIQUOR/DRUGS"
[37] "M-14 SEMIAUTOMATIC ASSAULT RIFLE"
[38] "M1-1 SEMIAUTOMATIC ASSAULT RIFLE"
[39] "MAC-10 SEMIAUTOMATIC ASSAULT WEAPON"
[40] "MAC-11 SEMIAUTOMATIC ASSAULT WEAPON"
[41] "MACE/PEPPER SPRAY"
[42] "MACHETE"
[43] "MARTIAL ARTS WEAPONS"
[44] "OTHER CUTTING INSTRUMENT"
[45] "OTHER FIREARM"
[46] "OTHER KNIFE"
[47] "PHYSICAL PRESENCE"
[48] "PIPE/METAL PIPE"
[49] "RAZOR"
[50] "RAZOR BLADE"
[51] "RELIC FIREARM"
[52] "REVOLVER"
[53] "RIFLE"
[54] "ROCK/THROWN OBJECT"
[55] "ROPE/LIGATURE"
[56] "SAWED OFF RIFLE/SHOTGUN"
[57] "SCALDING LIQUID"
[58] "SCISSORS"
[59] "SCREWDRIVER"
[60] "SEMI-AUTOMATIC PISTOL"
[61] "SEMI-AUTOMATIC RIFLE"
[62] "SHOTGUN"
[63] "SIMULATED GUN"
[64] "STARTER PISTOL/REVOLVER"
[65] "STICK"
[66] "STRAIGHT RAZOR"
[67] "STRONG-ARM (HANDS, FIST, FEET OR BODILY FORCE)"
[68] "STUN GUN"
[69] "SWITCH BLADE"
[70] "SWORD"
[71] "SYRINGE"
[72] "TIRE IRON"
[73] "TOY GUN"
[74] "UNK TYPE SEMIAUTOMATIC ASSAULT RIFLE"
[75] "UNKNOWN FIREARM"
[76] "UNKNOWN TYPE CUTTING INSTRUMENT"
[77] "UNKNOWN WEAPON/OTHER WEAPON"
[78] "UZI SEMIAUTOMATIC ASSAULT RIFLE"
[79] "VEHICLE"
[80] "VERBAL THREAT"
最佳答案
库(dplyr)
example <- data.frame(key = c(1:10),
values = c("knife", "gun", "bomb", "fork",
"ball", "dog", "cat", "paper",
"redfish", "honey")
)
key values
1 1 knife
2 2 gun
3 3 bomb
4 4 fork
5 5 ball
6 6 dog
example %>%
mutate(newValues = case_when(
grepl(x = values, pattern = "knife|gun|bomb") ~ "weapon",
grepl(x = values, pattern = "fork|ball|paper|honey") ~ "other",
grepl(x = values, pattern = "cat|dog|redfish") ~ "pet",
TRUE ~ "Unkwown")
)
key values newValues
1 1 knife weapon
2 2 gun weapon
3 3 bomb weapon
4 4 fork other
5 5 ball other
6 6 dog pet
注意:1. 如果您不想创建新列，只需重新分配相同的列即可； 2. 如果您需要一个因子，只需将 case_when 的结果通过管道传输到 factor
关于减少同一列中的因子水平，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/49439495/