Intersect coordinates with spatial polygon with R

Question

I get the shapeline of newyork census tract from library tigris,after i have a lot of point,in coordinates get from the new york police department

library(tigris)
tracts <- tracts(state = 'NY', county = c(5, 47, 61, 81, 85), cb=TRUE)

for the reproducibility i put some of my point coordinates:

mydata=
        Latitude Longitude
    1   40.71108 -73.85472
    2   40.66888 -73.93251
    3   40.82708 -73.86241
    4   40.68076 -73.95389
    5   40.82449 -73.91253
    6   40.88475 -73.86385
    7   40.76403 -73.97858
    8   40.72972 -73.86397
    9   40.86285 -73.89958
    10  40.57603 -74.09003
    11  40.65729 -73.73765
    12  40.84034 -73.92200
    13  40.76732 -73.98430
    14  40.76039 -73.91510
    15  40.72176 -73.84581
    16  40.69129 -73.91738
    17  40.57487 -74.16973
    18  40.61622 -74.03403
    19  40.63404 -73.96016
    20  40.75528 -73.93629

The main problem (i think) is that Coordinate Reference System (CRS) arguments of my data is NA.So when i try to intersect mydata with tracts, my result is NA,even if i plot the two things together i get only the image of tracts without mydata. I tried, watching around the web:

proj4string(mydata)<-proj4string(tracts)

But this didn't solve my problem.

edit: Also i tried to read the shapefile with readShapePoly that lose the CRS,but it didn't work.

Answer 1

Because New York City coordinates are about 40.7128° N, 74.0060° W (source: Google), it appears evident that the column names in the header of mydata are inverted.