This function adds an integer column of 1
's to data
.
Arguments
- data
A data frame or matrix.
- name
The name for the intercept column. Defaults to
"(Intercept)"
, which is the same name thatstats::lm()
uses.
Details
If a column named name
already exists in data
, then data
is returned
unchanged and a warning is issued.
Examples
add_intercept_column(mtcars)
#> (Intercept) mpg cyl disp hp drat wt qsec vs am
#> Mazda RX4 1 21.0 6 160.0 110 3.90 2.620 16.46 0 1
#> Mazda RX4 Wag 1 21.0 6 160.0 110 3.90 2.875 17.02 0 1
#> Datsun 710 1 22.8 4 108.0 93 3.85 2.320 18.61 1 1
#> Hornet 4 Drive 1 21.4 6 258.0 110 3.08 3.215 19.44 1 0
#> Hornet Sportabout 1 18.7 8 360.0 175 3.15 3.440 17.02 0 0
#> Valiant 1 18.1 6 225.0 105 2.76 3.460 20.22 1 0
#> Duster 360 1 14.3 8 360.0 245 3.21 3.570 15.84 0 0
#> Merc 240D 1 24.4 4 146.7 62 3.69 3.190 20.00 1 0
#> Merc 230 1 22.8 4 140.8 95 3.92 3.150 22.90 1 0
#> Merc 280 1 19.2 6 167.6 123 3.92 3.440 18.30 1 0
#> Merc 280C 1 17.8 6 167.6 123 3.92 3.440 18.90 1 0
#> Merc 450SE 1 16.4 8 275.8 180 3.07 4.070 17.40 0 0
#> Merc 450SL 1 17.3 8 275.8 180 3.07 3.730 17.60 0 0
#> Merc 450SLC 1 15.2 8 275.8 180 3.07 3.780 18.00 0 0
#> Cadillac Fleetwood 1 10.4 8 472.0 205 2.93 5.250 17.98 0 0
#> Lincoln Continental 1 10.4 8 460.0 215 3.00 5.424 17.82 0 0
#> Chrysler Imperial 1 14.7 8 440.0 230 3.23 5.345 17.42 0 0
#> Fiat 128 1 32.4 4 78.7 66 4.08 2.200 19.47 1 1
#> Honda Civic 1 30.4 4 75.7 52 4.93 1.615 18.52 1 1
#> Toyota Corolla 1 33.9 4 71.1 65 4.22 1.835 19.90 1 1
#> Toyota Corona 1 21.5 4 120.1 97 3.70 2.465 20.01 1 0
#> Dodge Challenger 1 15.5 8 318.0 150 2.76 3.520 16.87 0 0
#> AMC Javelin 1 15.2 8 304.0 150 3.15 3.435 17.30 0 0
#> Camaro Z28 1 13.3 8 350.0 245 3.73 3.840 15.41 0 0
#> Pontiac Firebird 1 19.2 8 400.0 175 3.08 3.845 17.05 0 0
#> Fiat X1-9 1 27.3 4 79.0 66 4.08 1.935 18.90 1 1
#> Porsche 914-2 1 26.0 4 120.3 91 4.43 2.140 16.70 0 1
#> Lotus Europa 1 30.4 4 95.1 113 3.77 1.513 16.90 1 1
#> Ford Pantera L 1 15.8 8 351.0 264 4.22 3.170 14.50 0 1
#> Ferrari Dino 1 19.7 6 145.0 175 3.62 2.770 15.50 0 1
#> Maserati Bora 1 15.0 8 301.0 335 3.54 3.570 14.60 0 1
#> Volvo 142E 1 21.4 4 121.0 109 4.11 2.780 18.60 1 1
#> gear carb
#> Mazda RX4 4 4
#> Mazda RX4 Wag 4 4
#> Datsun 710 4 1
#> Hornet 4 Drive 3 1
#> Hornet Sportabout 3 2
#> Valiant 3 1
#> Duster 360 3 4
#> Merc 240D 4 2
#> Merc 230 4 2
#> Merc 280 4 4
#> Merc 280C 4 4
#> Merc 450SE 3 3
#> Merc 450SL 3 3
#> Merc 450SLC 3 3
#> Cadillac Fleetwood 3 4
#> Lincoln Continental 3 4
#> Chrysler Imperial 3 4
#> Fiat 128 4 1
#> Honda Civic 4 2
#> Toyota Corolla 4 1
#> Toyota Corona 3 1
#> Dodge Challenger 3 2
#> AMC Javelin 3 2
#> Camaro Z28 3 4
#> Pontiac Firebird 3 2
#> Fiat X1-9 4 1
#> Porsche 914-2 5 2
#> Lotus Europa 5 2
#> Ford Pantera L 5 4
#> Ferrari Dino 5 6
#> Maserati Bora 5 8
#> Volvo 142E 4 2
add_intercept_column(mtcars, "intercept")
#> intercept mpg cyl disp hp drat wt qsec vs am
#> Mazda RX4 1 21.0 6 160.0 110 3.90 2.620 16.46 0 1
#> Mazda RX4 Wag 1 21.0 6 160.0 110 3.90 2.875 17.02 0 1
#> Datsun 710 1 22.8 4 108.0 93 3.85 2.320 18.61 1 1
#> Hornet 4 Drive 1 21.4 6 258.0 110 3.08 3.215 19.44 1 0
#> Hornet Sportabout 1 18.7 8 360.0 175 3.15 3.440 17.02 0 0
#> Valiant 1 18.1 6 225.0 105 2.76 3.460 20.22 1 0
#> Duster 360 1 14.3 8 360.0 245 3.21 3.570 15.84 0 0
#> Merc 240D 1 24.4 4 146.7 62 3.69 3.190 20.00 1 0
#> Merc 230 1 22.8 4 140.8 95 3.92 3.150 22.90 1 0
#> Merc 280 1 19.2 6 167.6 123 3.92 3.440 18.30 1 0
#> Merc 280C 1 17.8 6 167.6 123 3.92 3.440 18.90 1 0
#> Merc 450SE 1 16.4 8 275.8 180 3.07 4.070 17.40 0 0
#> Merc 450SL 1 17.3 8 275.8 180 3.07 3.730 17.60 0 0
#> Merc 450SLC 1 15.2 8 275.8 180 3.07 3.780 18.00 0 0
#> Cadillac Fleetwood 1 10.4 8 472.0 205 2.93 5.250 17.98 0 0
#> Lincoln Continental 1 10.4 8 460.0 215 3.00 5.424 17.82 0 0
#> Chrysler Imperial 1 14.7 8 440.0 230 3.23 5.345 17.42 0 0
#> Fiat 128 1 32.4 4 78.7 66 4.08 2.200 19.47 1 1
#> Honda Civic 1 30.4 4 75.7 52 4.93 1.615 18.52 1 1
#> Toyota Corolla 1 33.9 4 71.1 65 4.22 1.835 19.90 1 1
#> Toyota Corona 1 21.5 4 120.1 97 3.70 2.465 20.01 1 0
#> Dodge Challenger 1 15.5 8 318.0 150 2.76 3.520 16.87 0 0
#> AMC Javelin 1 15.2 8 304.0 150 3.15 3.435 17.30 0 0
#> Camaro Z28 1 13.3 8 350.0 245 3.73 3.840 15.41 0 0
#> Pontiac Firebird 1 19.2 8 400.0 175 3.08 3.845 17.05 0 0
#> Fiat X1-9 1 27.3 4 79.0 66 4.08 1.935 18.90 1 1
#> Porsche 914-2 1 26.0 4 120.3 91 4.43 2.140 16.70 0 1
#> Lotus Europa 1 30.4 4 95.1 113 3.77 1.513 16.90 1 1
#> Ford Pantera L 1 15.8 8 351.0 264 4.22 3.170 14.50 0 1
#> Ferrari Dino 1 19.7 6 145.0 175 3.62 2.770 15.50 0 1
#> Maserati Bora 1 15.0 8 301.0 335 3.54 3.570 14.60 0 1
#> Volvo 142E 1 21.4 4 121.0 109 4.11 2.780 18.60 1 1
#> gear carb
#> Mazda RX4 4 4
#> Mazda RX4 Wag 4 4
#> Datsun 710 4 1
#> Hornet 4 Drive 3 1
#> Hornet Sportabout 3 2
#> Valiant 3 1
#> Duster 360 3 4
#> Merc 240D 4 2
#> Merc 230 4 2
#> Merc 280 4 4
#> Merc 280C 4 4
#> Merc 450SE 3 3
#> Merc 450SL 3 3
#> Merc 450SLC 3 3
#> Cadillac Fleetwood 3 4
#> Lincoln Continental 3 4
#> Chrysler Imperial 3 4
#> Fiat 128 4 1
#> Honda Civic 4 2
#> Toyota Corolla 4 1
#> Toyota Corona 3 1
#> Dodge Challenger 3 2
#> AMC Javelin 3 2
#> Camaro Z28 3 4
#> Pontiac Firebird 3 2
#> Fiat X1-9 4 1
#> Porsche 914-2 5 2
#> Lotus Europa 5 2
#> Ford Pantera L 5 4
#> Ferrari Dino 5 6
#> Maserati Bora 5 8
#> Volvo 142E 4 2
add_intercept_column(as.matrix(mtcars))
#> (Intercept) mpg cyl disp hp drat wt qsec vs am
#> Mazda RX4 1 21.0 6 160.0 110 3.90 2.620 16.46 0 1
#> Mazda RX4 Wag 1 21.0 6 160.0 110 3.90 2.875 17.02 0 1
#> Datsun 710 1 22.8 4 108.0 93 3.85 2.320 18.61 1 1
#> Hornet 4 Drive 1 21.4 6 258.0 110 3.08 3.215 19.44 1 0
#> Hornet Sportabout 1 18.7 8 360.0 175 3.15 3.440 17.02 0 0
#> Valiant 1 18.1 6 225.0 105 2.76 3.460 20.22 1 0
#> Duster 360 1 14.3 8 360.0 245 3.21 3.570 15.84 0 0
#> Merc 240D 1 24.4 4 146.7 62 3.69 3.190 20.00 1 0
#> Merc 230 1 22.8 4 140.8 95 3.92 3.150 22.90 1 0
#> Merc 280 1 19.2 6 167.6 123 3.92 3.440 18.30 1 0
#> Merc 280C 1 17.8 6 167.6 123 3.92 3.440 18.90 1 0
#> Merc 450SE 1 16.4 8 275.8 180 3.07 4.070 17.40 0 0
#> Merc 450SL 1 17.3 8 275.8 180 3.07 3.730 17.60 0 0
#> Merc 450SLC 1 15.2 8 275.8 180 3.07 3.780 18.00 0 0
#> Cadillac Fleetwood 1 10.4 8 472.0 205 2.93 5.250 17.98 0 0
#> Lincoln Continental 1 10.4 8 460.0 215 3.00 5.424 17.82 0 0
#> Chrysler Imperial 1 14.7 8 440.0 230 3.23 5.345 17.42 0 0
#> Fiat 128 1 32.4 4 78.7 66 4.08 2.200 19.47 1 1
#> Honda Civic 1 30.4 4 75.7 52 4.93 1.615 18.52 1 1
#> Toyota Corolla 1 33.9 4 71.1 65 4.22 1.835 19.90 1 1
#> Toyota Corona 1 21.5 4 120.1 97 3.70 2.465 20.01 1 0
#> Dodge Challenger 1 15.5 8 318.0 150 2.76 3.520 16.87 0 0
#> AMC Javelin 1 15.2 8 304.0 150 3.15 3.435 17.30 0 0
#> Camaro Z28 1 13.3 8 350.0 245 3.73 3.840 15.41 0 0
#> Pontiac Firebird 1 19.2 8 400.0 175 3.08 3.845 17.05 0 0
#> Fiat X1-9 1 27.3 4 79.0 66 4.08 1.935 18.90 1 1
#> Porsche 914-2 1 26.0 4 120.3 91 4.43 2.140 16.70 0 1
#> Lotus Europa 1 30.4 4 95.1 113 3.77 1.513 16.90 1 1
#> Ford Pantera L 1 15.8 8 351.0 264 4.22 3.170 14.50 0 1
#> Ferrari Dino 1 19.7 6 145.0 175 3.62 2.770 15.50 0 1
#> Maserati Bora 1 15.0 8 301.0 335 3.54 3.570 14.60 0 1
#> Volvo 142E 1 21.4 4 121.0 109 4.11 2.780 18.60 1 1
#> gear carb
#> Mazda RX4 4 4
#> Mazda RX4 Wag 4 4
#> Datsun 710 4 1
#> Hornet 4 Drive 3 1
#> Hornet Sportabout 3 2
#> Valiant 3 1
#> Duster 360 3 4
#> Merc 240D 4 2
#> Merc 230 4 2
#> Merc 280 4 4
#> Merc 280C 4 4
#> Merc 450SE 3 3
#> Merc 450SL 3 3
#> Merc 450SLC 3 3
#> Cadillac Fleetwood 3 4
#> Lincoln Continental 3 4
#> Chrysler Imperial 3 4
#> Fiat 128 4 1
#> Honda Civic 4 2
#> Toyota Corolla 4 1
#> Toyota Corona 3 1
#> Dodge Challenger 3 2
#> AMC Javelin 3 2
#> Camaro Z28 3 4
#> Pontiac Firebird 3 2
#> Fiat X1-9 4 1
#> Porsche 914-2 5 2
#> Lotus Europa 5 2
#> Ford Pantera L 5 4
#> Ferrari Dino 5 6
#> Maserati Bora 5 8
#> Volvo 142E 4 2