bat_02 <- Batting %>% filter(yearID %in% 1999:2001) %>%
mutate(pa = AB + BB, singles = (H - X2B - X3B - HR)/pa, bb = BB/pa) %>%
filter(pa >= 100) %>%
select(playerID, singles, bb)
bat_02 %>%
group_by(playerID) %>%
summarize(avg1 = mean(singles))
# A tibble: 580 x 2
playerID avg1
<chr> <dbl>
1 abbotje01 0.169
2 abbotku01 0.143
3 abernbr01 0.178
4 abreubo01 0.153
5 agbaybe01 0.162
6 alexama02 0.166
7 alfoned01 0.161
8 alicelu01 0.168
9 allench01 0.165
10 alomaro01 0.186
# ... with 570 more rows
> sum(avg1 > 0.2)
Error: object 'avg1' not found