Discussion12
Keeno Glanville
2023-04-21
Determine if the average price of a house in NY is decreasing or increasing compared to one year ago. Will involve turning the months/years into a long format.
Load data
urldat <- "https://raw.githubusercontent.com/kglan/MSDS/main/DATA605/Regression%20Analysis/CarPrice_Assignment.csv"
zill<- read_csv(url(urldat))## Rows: 205 Columns: 26
## ── Column specification ────────────────────────────────────────────────────────
## Delimiter: ","
## chr (10): CarName, fueltype, aspiration, doornumber, carbody, drivewheel, en...
## dbl (16): car_ID, symboling, wheelbase, carlength, carwidth, carheight, curb...
##
## ℹ Use `spec()` to retrieve the full column specification for this data.
## ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.zill## # A tibble: 205 × 26
## car_ID symboling CarName fuelt…¹ aspir…² doorn…³ carbody drive…⁴ engin…⁵
## <dbl> <dbl> <chr> <chr> <chr> <chr> <chr> <chr> <chr>
## 1 1 3 alfa-romero… gas std two conver… rwd front
## 2 2 3 alfa-romero… gas std two conver… rwd front
## 3 3 1 alfa-romero… gas std two hatchb… rwd front
## 4 4 2 audi 100 ls gas std four sedan fwd front
## 5 5 2 audi 100ls gas std four sedan 4wd front
## 6 6 2 audi fox gas std two sedan fwd front
## 7 7 1 audi 100ls gas std four sedan fwd front
## 8 8 1 audi 5000 gas std four wagon fwd front
## 9 9 1 audi 4000 gas turbo four sedan fwd front
## 10 10 0 audi 5000s … gas turbo two hatchb… 4wd front
## # … with 195 more rows, 17 more variables: wheelbase <dbl>, carlength <dbl>,
## # carwidth <dbl>, carheight <dbl>, curbweight <dbl>, enginetype <chr>,
## # cylindernumber <chr>, enginesize <dbl>, fuelsystem <chr>, boreratio <dbl>,
## # stroke <dbl>, compressionratio <dbl>, horsepower <dbl>, peakrpm <dbl>,
## # citympg <dbl>, highwaympg <dbl>, price <dbl>, and abbreviated variable
## # names ¹fueltype, ²aspiration, ³doornumber, ⁴drivewheel, ⁵enginelocationMultiple Regression
model <- lm(price~., data =zill)
summary(model)##
## Call:
## lm(formula = price ~ ., data = zill)
##
## Residuals:
## Min 1Q Median 3Q Max
## -1576 0 0 0 1421
##
## Coefficients: (12 not defined because of singularities)
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) 1464.060 24067.028 0.061 0.951958
## car_ID 153.076 64.684 2.367 0.025687
## symboling 725.668 323.690 2.242 0.033723
## CarNamealfa-romero Quadrifoglio 5339.290 4141.961 1.289 0.208724
## CarNamealfa-romero stelvio 2851.924 1556.345 1.832 0.078362
## CarNameaudi 100 ls 3980.044 3341.799 1.191 0.244418
## CarNameaudi 100ls 5440.965 3939.323 1.381 0.178976
## CarNameaudi 4000 9453.414 4893.730 1.932 0.064359
## CarNameaudi 5000 7315.676 4148.741 1.763 0.089593
## CarNameaudi 5000s (diesel) 5048.734 4806.719 1.050 0.303223
## CarNameaudi fox 8004.584 3850.889 2.079 0.047659
## CarNamebmw 320i 3665.224 2932.400 1.250 0.222468
## CarNamebmw x1 16398.848 4064.364 4.035 0.000427
## CarNamebmw x3 15669.006 3870.528 4.048 0.000412
## CarNamebmw x4 16597.885 4245.075 3.910 0.000591
## CarNamebmw x5 26105.388 4116.060 6.342 1.02e-06
## CarNamebmw z4 15092.926 4104.480 3.677 0.001079
## CarNamebuick century 3394.510 6114.139 0.555 0.583510
## CarNamebuick century luxus (sw) 2830.130 6144.487 0.461 0.648917
## CarNamebuick century special 315.888 5317.826 0.059 0.953086
## CarNamebuick electra 225 custom -238.538 5517.392 -0.043 0.965845
## CarNamebuick opel isuzu deluxe -2746.797 4648.634 -0.591 0.559701
## CarNamebuick regal sport coupe (turbo) 8247.321 5282.930 1.561 0.130585
## CarNamebuick skyhawk 2498.152 5625.634 0.444 0.660669
## CarNamebuick skylark -2256.734 5472.035 -0.412 0.683418
## CarNamechevrolet impala 745.695 4422.267 0.169 0.867398
## CarNamechevrolet monte carlo -5791.923 3932.695 -1.473 0.152819
## CarNamechevrolet vega 2300 -6942.823 3806.475 -1.824 0.079675
## CarNamedodge challenger se -5644.893 3638.855 -1.551 0.132922
## CarNamedodge colt (sw) -8616.639 3757.617 -2.293 0.030177
## CarNamedodge colt hardtop -9380.564 3719.607 -2.522 0.018133
## CarNamedodge coronet custom -8832.211 3661.983 -2.412 0.023229
## CarNamedodge coronet custom (sw) -5385.044 4548.548 -1.184 0.247162
## CarNamedodge d200 -7061.034 3456.794 -2.043 0.051348
## CarNamedodge dart custom -3481.303 3974.749 -0.876 0.389129
## CarNamedodge monaco (sw) -8467.722 3715.083 -2.279 0.031099
## CarNamedodge rampage -7760.845 3894.157 -1.993 0.056861
## CarNamehonda accord -3275.628 5032.000 -0.651 0.520785
## CarNamehonda accord cvcc -6814.723 4655.065 -1.464 0.155198
## CarNamehonda accord lx -5594.750 4749.667 -1.178 0.249496
## CarNamehonda civic -4621.260 4100.458 -1.127 0.270032
## CarNamehonda civic (auto) -8117.608 4535.662 -1.790 0.085153
## CarNamehonda civic 1300 -3924.742 4903.031 -0.800 0.430691
## CarNamehonda civic 1500 gl -3391.219 5103.479 -0.664 0.512227
## CarNamehonda civic cvcc -5930.849 4596.581 -1.290 0.208313
## CarNamehonda prelude -4625.080 4938.351 -0.937 0.357602
## CarNameisuzu D-Max -7981.442 4919.273 -1.622 0.116765
## CarNameisuzu D-Max V-Cross -9077.711 4862.983 -1.867 0.073261
## CarNameisuzu MU-X -7911.400 3885.498 -2.036 0.052043
## CarNamejaguar xf 160.068 3672.109 0.044 0.965564
## CarNamejaguar xj -2986.856 3661.432 -0.816 0.422047
## CarNamejaguar xk 4389.084 6753.443 0.650 0.521456
## CarNamemaxda glc deluxe -7881.451 4806.507 -1.640 0.113103
## CarNamemaxda rx3 -9080.132 4847.291 -1.873 0.072319
## CarNamemazda 626 -8611.028 4624.289 -1.862 0.073924
## CarNamemazda glc -6522.541 4440.118 -1.469 0.153829
## CarNamemazda glc 4 -6814.221 5650.857 -1.206 0.238726
## CarNamemazda glc custom -8221.173 4826.224 -1.703 0.100412
## CarNamemazda glc custom l -11155.639 4696.154 -2.375 0.025183
## CarNamemazda glc deluxe -8189.991 4851.734 -1.688 0.103362
## CarNamemazda rx-4 -9168.168 4685.529 -1.957 0.061203
## CarNamemazda rx-7 gs -5694.495 4599.115 -1.238 0.226716
## CarNamemazda rx2 coupe -7388.763 4860.722 -1.520 0.140556
## CarNamemercury cougar -8178.650 6009.231 -1.361 0.185190
## CarNamemitsubishi g4 -15717.851 6169.643 -2.548 0.017103
## CarNamemitsubishi lancer -16251.139 6357.561 -2.556 0.016772
## CarNamemitsubishi mirage -18099.163 6498.938 -2.785 0.009854
## CarNamemitsubishi mirage g4 -16070.951 6325.950 -2.540 0.017384
## CarNamemitsubishi montero -18648.094 6152.657 -3.031 0.005459
## CarNamemitsubishi outlander -17041.307 6287.017 -2.711 0.011737
## CarNamemitsubishi pajero -18035.063 6236.337 -2.892 0.007638
## CarNamenissan clipper -14461.607 7557.316 -1.914 0.066743
## CarNamenissan dayz -15537.918 7605.331 -2.043 0.051309
## CarNamenissan fuga -13801.149 8073.239 -1.709 0.099271
## CarNamenissan gt-r -15601.158 6975.502 -2.237 0.034110
## CarNamenissan juke -13042.895 7277.852 -1.792 0.084757
## CarNamenissan kicks -14465.254 8196.035 -1.765 0.089325
## CarNamenissan latio -14503.856 7078.671 -2.049 0.050685
## CarNamenissan leaf -13051.687 7260.070 -1.798 0.083843
## CarNamenissan note -12338.572 7463.771 -1.653 0.110331
## CarNamenissan nv200 -16025.649 7182.645 -2.231 0.034509
## CarNamenissan otti -15060.861 7682.618 -1.960 0.060749
## CarNamenissan rogue -14305.794 7032.968 -2.034 0.052261
## CarNamenissan teana -15631.312 7879.622 -1.984 0.057934
## CarNamenissan titan -12235.253 7220.538 -1.695 0.102116
## CarNameNissan versa -13413.773 6942.545 -1.932 0.064311
## CarNamepeugeot 304 -26389.554 6262.505 -4.214 0.000267
## CarNamepeugeot 504 -23978.749 6402.633 -3.745 0.000906
## CarNamepeugeot 504 (sw) -23709.629 6380.998 -3.716 0.000977
## CarNamepeugeot 505s turbo diesel -22733.899 6714.965 -3.386 0.002266
## CarNamepeugeot 604sl -24539.992 6577.093 -3.731 0.000939
## CarNameplymouth cricket -21289.464 8681.516 -2.452 0.021222
## CarNameplymouth duster -23294.031 8326.902 -2.797 0.009567
## CarNameplymouth fury gran sedan -23615.334 8797.386 -2.684 0.012478
## CarNameplymouth fury iii -23123.441 8818.842 -2.622 0.014418
## CarNameplymouth satellite custom (sw) -21743.841 8711.085 -2.496 0.019226
## CarNameplymouth valiant -17988.655 8785.531 -2.048 0.050834
## CarNameporcshce panamera -4303.206 10526.456 -0.409 0.686035
## CarNameporsche boxter 393.465 11113.478 0.035 0.972028
## CarNameporsche cayenne -2956.282 10465.289 -0.282 0.779809
## CarNameporsche macan -12031.956 8866.189 -1.357 0.186427
## CarNamerenault 12tl -17786.564 8646.623 -2.057 0.049843
## CarNamerenault 5 gtl -20579.681 8556.385 -2.405 0.023577
## CarNamesaab 99e -16370.556 9256.390 -1.769 0.088699
## CarNamesaab 99gle -15269.026 9336.815 -1.635 0.114025
## CarNamesaab 99le -18228.042 9231.742 -1.974 0.059036
## CarNamesubaru -27076.490 9392.453 -2.883 0.007808
## CarNamesubaru baja -25469.712 9011.549 -2.826 0.008933
## CarNamesubaru brz -24260.657 9253.575 -2.622 0.014427
## CarNamesubaru dl -24848.991 9321.737 -2.666 0.013031
## CarNamesubaru r1 -26140.178 9207.082 -2.839 0.008665
## CarNamesubaru r2 -25641.614 8827.539 -2.905 0.007408
## CarNamesubaru trezia -25979.569 9701.227 -2.678 0.012665
## CarNamesubaru tribeca -24222.721 9501.112 -2.549 0.017031
## CarNametoyota carina -28409.459 11515.664 -2.467 0.020530
## CarNametoyota celica gt -25805.686 11595.954 -2.225 0.034939
## CarNametoyota celica gt liftback -31145.270 10832.939 -2.875 0.007953
## CarNametoyota corolla -24934.252 10863.751 -2.295 0.030042
## CarNametoyota corolla 1200 -25121.115 10594.321 -2.371 0.025424
## CarNametoyota corolla 1600 (sw) -20241.570 10685.135 -1.894 0.069351
## CarNametoyota corolla liftback -25071.958 10936.948 -2.292 0.030223
## CarNametoyota corolla tercel -30453.878 10869.368 -2.802 0.009468
## CarNametoyota corona -25299.866 10843.154 -2.333 0.027640
## CarNametoyota corona hardtop -21796.585 11027.174 -1.977 0.058781
## CarNametoyota corona liftback -26119.358 10798.687 -2.419 0.022875
## CarNametoyota corona mark ii -25795.352 10651.811 -2.422 0.022725
## CarNametoyota cressida -20941.386 11637.854 -1.799 0.083570
## CarNametoyota mark ii -24785.364 10883.275 -2.277 0.031228
## CarNametoyota starlet -25091.653 10746.339 -2.335 0.027541
## CarNametoyota tercel -25336.364 11071.265 -2.288 0.030483
## CarNametoyouta tercel -22470.447 11167.292 -2.012 0.054670
## CarNamevokswagen rabbit -28146.900 12718.048 -2.213 0.035870
## CarNamevolkswagen 1131 deluxe sedan -28350.471 12222.975 -2.319 0.028491
## CarNamevolkswagen 411 (sw) -30294.826 12296.250 -2.464 0.020682
## CarNamevolkswagen dasher -27412.373 12723.706 -2.154 0.040649
## CarNamevolkswagen model 111 -29554.798 12696.486 -2.328 0.027974
## CarNamevolkswagen rabbit -23080.543 12503.588 -1.846 0.076321
## CarNamevolkswagen rabbit custom -25478.948 13041.257 -1.954 0.061573
## CarNamevolkswagen super beetle -28172.032 13054.263 -2.158 0.040337
## CarNamevolkswagen type 3 -29758.368 12203.867 -2.438 0.021890
## CarNamevolvo 144ea -27427.953 12668.497 -2.165 0.039744
## CarNamevolvo 145e (sw) -29127.275 12239.829 -2.380 0.024949
## CarNamevolvo 244dl -26297.009 12404.001 -2.120 0.043706
## CarNamevolvo 245 -25251.993 12782.992 -1.975 0.058923
## CarNamevolvo 246 -21108.975 13339.878 -1.582 0.125649
## CarNamevolvo 264gl -25037.924 12552.574 -1.995 0.056664
## CarNamevolvo diesel -23910.405 13115.100 -1.823 0.079804
## CarNamevw dasher -27150.785 13299.630 -2.041 0.051474
## CarNamevw rabbit -30000.371 12770.604 -2.349 0.026690
## fueltypegas -27422.306 9966.212 -2.752 0.010662
## aspirationturbo 236.211 986.002 0.240 0.812547
## doornumbertwo -1289.204 726.157 -1.775 0.087544
## carbodyhardtop 980.106 1811.658 0.541 0.593113
## carbodyhatchback 1074.707 1218.575 0.882 0.385892
## carbodysedan 2058.832 1031.011 1.997 0.056403
## carbodywagon NA NA NA NA
## drivewheelfwd 220.466 1260.739 0.175 0.862536
## drivewheelrwd 697.180 1435.842 0.486 0.631350
## enginelocationrear 9158.974 3987.839 2.297 0.029940
## wheelbase 289.818 128.512 2.255 0.032766
## carlength -223.963 75.521 -2.966 0.006398
## carwidth 707.880 306.717 2.308 0.029218
## carheight -461.834 272.256 -1.696 0.101767
## curbweight 10.847 3.395 3.195 0.003650
## enginetypedohcv NA NA NA NA
## enginetypel NA NA NA NA
## enginetypeohc -3823.290 1866.254 -2.049 0.050717
## enginetypeohcf NA NA NA NA
## enginetypeohcv 804.447 2282.580 0.352 0.727358
## enginetyperotor 6623.579 3942.157 1.680 0.104898
## cylindernumberfive NA NA NA NA
## cylindernumberfour 7150.023 2131.208 3.355 0.002447
## cylindernumbersix NA NA NA NA
## cylindernumberthree NA NA NA NA
## cylindernumbertwelve NA NA NA NA
## cylindernumbertwo NA NA NA NA
## enginesize 55.532 50.444 1.101 0.281043
## fuelsystem2bbl 3954.307 2726.010 1.451 0.158854
## fuelsystem4bbl NA NA NA NA
## fuelsystemidi NA NA NA NA
## fuelsystemmfi NA NA NA NA
## fuelsystemmpfi 2993.555 2482.520 1.206 0.238733
## fuelsystemspdi 2526.711 3442.636 0.734 0.469549
## fuelsystemspfi 2068.375 4073.432 0.508 0.615894
## boreratio -3484.606 1792.683 -1.944 0.062818
## stroke -1314.657 1072.834 -1.225 0.231407
## compressionratio -1910.210 772.424 -2.473 0.020255
## horsepower -42.876 34.010 -1.261 0.218616
## peakrpm 3.286 1.008 3.261 0.003099
## citympg 309.298 223.210 1.386 0.177618
## highwaympg -124.218 164.066 -0.757 0.455783
##
## (Intercept)
## car_ID *
## symboling *
## CarNamealfa-romero Quadrifoglio
## CarNamealfa-romero stelvio .
## CarNameaudi 100 ls
## CarNameaudi 100ls
## CarNameaudi 4000 .
## CarNameaudi 5000 .
## CarNameaudi 5000s (diesel)
## CarNameaudi fox *
## CarNamebmw 320i
## CarNamebmw x1 ***
## CarNamebmw x3 ***
## CarNamebmw x4 ***
## CarNamebmw x5 ***
## CarNamebmw z4 **
## CarNamebuick century
## CarNamebuick century luxus (sw)
## CarNamebuick century special
## CarNamebuick electra 225 custom
## CarNamebuick opel isuzu deluxe
## CarNamebuick regal sport coupe (turbo)
## CarNamebuick skyhawk
## CarNamebuick skylark
## CarNamechevrolet impala
## CarNamechevrolet monte carlo
## CarNamechevrolet vega 2300 .
## CarNamedodge challenger se
## CarNamedodge colt (sw) *
## CarNamedodge colt hardtop *
## CarNamedodge coronet custom *
## CarNamedodge coronet custom (sw)
## CarNamedodge d200 .
## CarNamedodge dart custom
## CarNamedodge monaco (sw) *
## CarNamedodge rampage .
## CarNamehonda accord
## CarNamehonda accord cvcc
## CarNamehonda accord lx
## CarNamehonda civic
## CarNamehonda civic (auto) .
## CarNamehonda civic 1300
## CarNamehonda civic 1500 gl
## CarNamehonda civic cvcc
## CarNamehonda prelude
## CarNameisuzu D-Max
## CarNameisuzu D-Max V-Cross .
## CarNameisuzu MU-X .
## CarNamejaguar xf
## CarNamejaguar xj
## CarNamejaguar xk
## CarNamemaxda glc deluxe
## CarNamemaxda rx3 .
## CarNamemazda 626 .
## CarNamemazda glc
## CarNamemazda glc 4
## CarNamemazda glc custom
## CarNamemazda glc custom l *
## CarNamemazda glc deluxe
## CarNamemazda rx-4 .
## CarNamemazda rx-7 gs
## CarNamemazda rx2 coupe
## CarNamemercury cougar
## CarNamemitsubishi g4 *
## CarNamemitsubishi lancer *
## CarNamemitsubishi mirage **
## CarNamemitsubishi mirage g4 *
## CarNamemitsubishi montero **
## CarNamemitsubishi outlander *
## CarNamemitsubishi pajero **
## CarNamenissan clipper .
## CarNamenissan dayz .
## CarNamenissan fuga .
## CarNamenissan gt-r *
## CarNamenissan juke .
## CarNamenissan kicks .
## CarNamenissan latio .
## CarNamenissan leaf .
## CarNamenissan note
## CarNamenissan nv200 *
## CarNamenissan otti .
## CarNamenissan rogue .
## CarNamenissan teana .
## CarNamenissan titan
## CarNameNissan versa .
## CarNamepeugeot 304 ***
## CarNamepeugeot 504 ***
## CarNamepeugeot 504 (sw) ***
## CarNamepeugeot 505s turbo diesel **
## CarNamepeugeot 604sl ***
## CarNameplymouth cricket *
## CarNameplymouth duster **
## CarNameplymouth fury gran sedan *
## CarNameplymouth fury iii *
## CarNameplymouth satellite custom (sw) *
## CarNameplymouth valiant .
## CarNameporcshce panamera
## CarNameporsche boxter
## CarNameporsche cayenne
## CarNameporsche macan
## CarNamerenault 12tl *
## CarNamerenault 5 gtl *
## CarNamesaab 99e .
## CarNamesaab 99gle
## CarNamesaab 99le .
## CarNamesubaru **
## CarNamesubaru baja **
## CarNamesubaru brz *
## CarNamesubaru dl *
## CarNamesubaru r1 **
## CarNamesubaru r2 **
## CarNamesubaru trezia *
## CarNamesubaru tribeca *
## CarNametoyota carina *
## CarNametoyota celica gt *
## CarNametoyota celica gt liftback **
## CarNametoyota corolla *
## CarNametoyota corolla 1200 *
## CarNametoyota corolla 1600 (sw) .
## CarNametoyota corolla liftback *
## CarNametoyota corolla tercel **
## CarNametoyota corona *
## CarNametoyota corona hardtop .
## CarNametoyota corona liftback *
## CarNametoyota corona mark ii *
## CarNametoyota cressida .
## CarNametoyota mark ii *
## CarNametoyota starlet *
## CarNametoyota tercel *
## CarNametoyouta tercel .
## CarNamevokswagen rabbit *
## CarNamevolkswagen 1131 deluxe sedan *
## CarNamevolkswagen 411 (sw) *
## CarNamevolkswagen dasher *
## CarNamevolkswagen model 111 *
## CarNamevolkswagen rabbit .
## CarNamevolkswagen rabbit custom .
## CarNamevolkswagen super beetle *
## CarNamevolkswagen type 3 *
## CarNamevolvo 144ea *
## CarNamevolvo 145e (sw) *
## CarNamevolvo 244dl *
## CarNamevolvo 245 .
## CarNamevolvo 246
## CarNamevolvo 264gl .
## CarNamevolvo diesel .
## CarNamevw dasher .
## CarNamevw rabbit *
## fueltypegas *
## aspirationturbo
## doornumbertwo .
## carbodyhardtop
## carbodyhatchback
## carbodysedan .
## carbodywagon
## drivewheelfwd
## drivewheelrwd
## enginelocationrear *
## wheelbase *
## carlength **
## carwidth *
## carheight
## curbweight **
## enginetypedohcv
## enginetypel
## enginetypeohc .
## enginetypeohcf
## enginetypeohcv
## enginetyperotor
## cylindernumberfive
## cylindernumberfour **
## cylindernumbersix
## cylindernumberthree
## cylindernumbertwelve
## cylindernumbertwo
## enginesize
## fuelsystem2bbl
## fuelsystem4bbl
## fuelsystemidi
## fuelsystemmfi
## fuelsystemmpfi
## fuelsystemspdi
## fuelsystemspfi
## boreratio .
## stroke
## compressionratio *
## horsepower
## peakrpm **
## citympg
## highwaympg
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## Residual standard error: 1100 on 26 degrees of freedom
## Multiple R-squared: 0.9976, Adjusted R-squared: 0.9811
## F-statistic: 60.35 on 178 and 26 DF, p-value: < 2.2e-16plot(model)## Warning: not plotting observations with leverage one:
## 1, 2, 3, 4, 6, 8, 9, 10, 13, 15, 16, 17, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 34, 36, 37, 39, 40, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 59, 61, 62, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 86, 87, 90, 91, 94, 95, 96, 98, 101, 102, 103, 104, 105, 106, 109, 110, 115, 120, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 143, 144, 145, 146, 147, 148, 151, 154, 155, 156, 166, 167, 168, 171, 173, 175, 182, 183, 184, 185, 186, 187, 188, 190, 191, 192, 193, 198, 200, 204
## Warning in sqrt(crit * p * (1 - hh)/hh): NaNs produced## Warning in sqrt(crit * p * (1 - hh)/hh): NaNs produced
Change terms for binomial and quadratic
zill$fueltype <- ifelse(zill$fueltype == "gas", 1, 0)
zill$LxW <- zill$carlength * zill$carwidth
zill2<-zill%>%
select(-c(carlength, carwidth))Rerun model with additions
model2 <- lm(price~., data =zill2)
summary(model2)##
## Call:
## lm(formula = price ~ ., data = zill2)
##
## Residuals:
## Min 1Q Median 3Q Max
## -1632 0 0 0 1549
##
## Coefficients: (12 not defined because of singularities)
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) 1.441e+04 2.531e+04 0.569 0.573848
## car_ID 1.354e+02 7.415e+01 1.826 0.078934
## symboling 5.286e+02 3.644e+02 1.451 0.158393
## CarNamealfa-romero Quadrifoglio 4.528e+03 4.769e+03 0.949 0.350808
## CarNamealfa-romero stelvio 2.870e+03 1.794e+03 1.600 0.121324
## CarNameaudi 100 ls 2.618e+03 3.824e+03 0.685 0.499408
## CarNameaudi 100ls 5.013e+03 4.535e+03 1.105 0.278709
## CarNameaudi 4000 1.083e+04 5.613e+03 1.929 0.064283
## CarNameaudi 5000 9.098e+03 4.729e+03 1.924 0.064994
## CarNameaudi 5000s (diesel) 5.127e+03 5.541e+03 0.925 0.362977
## CarNameaudi fox 5.767e+03 4.364e+03 1.322 0.197403
## CarNamebmw 320i 8.973e+02 3.228e+03 0.278 0.783172
## CarNamebmw x1 1.434e+04 4.621e+03 3.102 0.004470
## CarNamebmw x3 1.455e+04 4.442e+03 3.275 0.002898
## CarNamebmw x4 1.337e+04 4.746e+03 2.816 0.008965
## CarNamebmw x5 2.277e+04 4.575e+03 4.977 3.24e-05
## CarNamebmw z4 1.413e+04 4.717e+03 2.995 0.005816
## CarNamebuick century 6.336e+03 6.972e+03 0.909 0.371458
## CarNamebuick century luxus (sw) 6.745e+03 6.951e+03 0.970 0.340455
## CarNamebuick century special -4.797e+03 5.763e+03 -0.832 0.412484
## CarNamebuick electra 225 custom 1.670e+03 6.325e+03 0.264 0.793823
## CarNamebuick opel isuzu deluxe -4.573e+03 5.284e+03 -0.865 0.394494
## CarNamebuick regal sport coupe (turbo) 5.373e+03 5.957e+03 0.902 0.375068
## CarNamebuick skyhawk 3.947e+03 6.455e+03 0.612 0.545965
## CarNamebuick skylark 1.345e+03 6.184e+03 0.218 0.829451
## CarNamechevrolet impala 9.799e+02 5.077e+03 0.193 0.848407
## CarNamechevrolet monte carlo -6.143e+03 4.536e+03 -1.354 0.186823
## CarNamechevrolet vega 2300 -7.217e+03 4.390e+03 -1.644 0.111798
## CarNamedodge challenger se -6.327e+03 4.183e+03 -1.512 0.142063
## CarNamedodge colt (sw) -8.247e+03 4.331e+03 -1.904 0.067588
## CarNamedodge colt hardtop -9.029e+03 4.288e+03 -2.106 0.044659
## CarNamedodge coronet custom -9.745e+03 4.196e+03 -2.323 0.027985
## CarNamedodge coronet custom (sw) -9.965e+03 4.957e+03 -2.010 0.054484
## CarNamedodge d200 -8.427e+03 3.942e+03 -2.138 0.041738
## CarNamedodge dart custom -4.314e+03 4.593e+03 -0.939 0.355908
## CarNamedodge monaco (sw) -8.414e+03 4.284e+03 -1.964 0.059868
## CarNamedodge rampage -8.312e+03 4.486e+03 -1.853 0.074867
## CarNamehonda accord -1.015e+04 5.198e+03 -1.952 0.061426
## CarNamehonda accord cvcc -1.005e+04 5.225e+03 -1.923 0.065099
## CarNamehonda accord lx -1.071e+04 5.133e+03 -2.087 0.046508
## CarNamehonda civic -6.595e+03 4.667e+03 -1.413 0.169079
## CarNamehonda civic (auto) -7.866e+03 5.236e+03 -1.502 0.144636
## CarNamehonda civic 1300 -9.357e+03 5.276e+03 -1.774 0.087412
## CarNamehonda civic 1500 gl -5.980e+03 5.816e+03 -1.028 0.313042
## CarNamehonda civic cvcc -8.730e+03 5.188e+03 -1.683 0.103981
## CarNamehonda prelude -1.076e+04 5.217e+03 -2.062 0.048902
## CarNameisuzu D-Max -7.663e+03 5.670e+03 -1.352 0.187735
## CarNameisuzu D-Max V-Cross -8.376e+03 5.602e+03 -1.495 0.146415
## CarNameisuzu MU-X -1.013e+04 4.385e+03 -2.310 0.028754
## CarNamejaguar xf -2.988e+03 4.021e+03 -0.743 0.463837
## CarNamejaguar xj -6.152e+03 4.007e+03 -1.536 0.136294
## CarNamejaguar xk 3.042e+03 7.706e+03 0.395 0.696157
## CarNamemaxda glc deluxe -7.573e+03 5.542e+03 -1.366 0.183087
## CarNamemaxda rx3 -8.329e+03 5.586e+03 -1.491 0.147553
## CarNamemazda 626 -9.243e+03 5.328e+03 -1.735 0.094184
## CarNamemazda glc -6.855e+03 5.122e+03 -1.338 0.191958
## CarNamemazda glc 4 -3.323e+03 6.402e+03 -0.519 0.607970
## CarNamemazda glc custom -9.190e+03 5.551e+03 -1.655 0.109427
## CarNamemazda glc custom l -1.161e+04 5.414e+03 -2.144 0.041198
## CarNamemazda glc deluxe -8.594e+03 5.593e+03 -1.537 0.136002
## CarNamemazda rx-4 -9.505e+03 5.402e+03 -1.760 0.089812
## CarNamemazda rx-7 gs -5.619e+03 5.309e+03 -1.058 0.299278
## CarNamemazda rx2 coupe -7.050e+03 5.604e+03 -1.258 0.219151
## CarNamemercury cougar -6.098e+03 6.900e+03 -0.884 0.384645
## CarNamemitsubishi g4 -1.553e+04 7.102e+03 -2.186 0.037650
## CarNamemitsubishi lancer -1.522e+04 7.318e+03 -2.080 0.047188
## CarNamemitsubishi mirage -1.700e+04 7.485e+03 -2.271 0.031304
## CarNamemitsubishi mirage g4 -1.602e+04 7.287e+03 -2.198 0.036684
## CarNamemitsubishi montero -1.859e+04 7.085e+03 -2.625 0.014107
## CarNamemitsubishi outlander -1.652e+04 7.242e+03 -2.281 0.030627
## CarNamemitsubishi pajero -1.787e+04 7.181e+03 -2.488 0.019309
## CarNamenissan clipper -1.341e+04 8.696e+03 -1.542 0.134601
## CarNamenissan dayz -1.675e+04 8.737e+03 -1.917 0.065830
## CarNamenissan fuga -1.359e+04 9.297e+03 -1.462 0.155251
## CarNamenissan gt-r -1.666e+04 8.024e+03 -2.077 0.047476
## CarNamenissan juke -1.352e+04 8.373e+03 -1.615 0.117887
## CarNamenissan kicks -1.124e+04 9.384e+03 -1.198 0.241501
## CarNamenissan latio -1.444e+04 8.152e+03 -1.771 0.087789
## CarNamenissan leaf -1.348e+04 8.356e+03 -1.613 0.118447
## CarNamenissan note -1.144e+04 8.594e+03 -1.331 0.194435
## CarNamenissan nv200 -1.645e+04 8.272e+03 -1.988 0.057023
## CarNamenissan otti -1.696e+04 8.805e+03 -1.926 0.064689
## CarNamenissan rogue -1.489e+04 8.095e+03 -1.839 0.076889
## CarNamenissan teana -1.275e+04 9.029e+03 -1.412 0.169444
## CarNamenissan titan -1.143e+04 8.315e+03 -1.375 0.180416
## CarNameNissan versa -1.407e+04 7.988e+03 -1.762 0.089409
## CarNamepeugeot 304 -2.592e+04 7.218e+03 -3.591 0.001293
## CarNamepeugeot 504 -2.313e+04 7.374e+03 -3.137 0.004094
## CarNamepeugeot 504 (sw) -2.337e+04 7.352e+03 -3.179 0.003686
## CarNamepeugeot 505s turbo diesel -2.202e+04 7.735e+03 -2.847 0.008330
## CarNamepeugeot 604sl -2.428e+04 7.582e+03 -3.203 0.003473
## CarNameplymouth cricket -2.017e+04 9.980e+03 -2.021 0.053296
## CarNameplymouth duster -2.168e+04 9.578e+03 -2.263 0.031875
## CarNameplymouth fury gran sedan -2.331e+04 1.012e+04 -2.304 0.029152
## CarNameplymouth fury iii -2.162e+04 1.014e+04 -2.133 0.042191
## CarNameplymouth satellite custom (sw) -2.154e+04 1.002e+04 -2.149 0.040732
## CarNameplymouth valiant -1.714e+04 1.013e+04 -1.692 0.102073
## CarNameporcshce panamera 3.693e+03 1.180e+04 0.313 0.756812
## CarNameporsche boxter 9.428e+03 1.241e+04 0.760 0.454081
## CarNameporsche cayenne 5.057e+03 1.173e+04 0.431 0.669791
## CarNameporsche macan -7.865e+03 1.012e+04 -0.777 0.443771
## CarNamerenault 12tl -1.744e+04 9.953e+03 -1.752 0.091127
## CarNamerenault 5 gtl -2.125e+04 9.835e+03 -2.161 0.039763
## CarNamesaab 99e -1.664e+04 1.066e+04 -1.562 0.130018
## CarNamesaab 99gle -1.545e+04 1.075e+04 -1.437 0.162087
## CarNamesaab 99le -1.844e+04 1.063e+04 -1.734 0.094243
## CarNamesubaru -2.571e+04 1.080e+04 -2.380 0.024654
## CarNamesubaru baja -2.510e+04 1.037e+04 -2.420 0.022510
## CarNamesubaru brz -2.252e+04 1.064e+04 -2.117 0.043582
## CarNamesubaru dl -2.246e+04 1.070e+04 -2.099 0.045280
## CarNamesubaru r1 -2.443e+04 1.058e+04 -2.309 0.028839
## CarNamesubaru r2 -2.494e+04 1.016e+04 -2.455 0.020800
## CarNamesubaru trezia -2.335e+04 1.114e+04 -2.096 0.045574
## CarNamesubaru tribeca -2.230e+04 1.092e+04 -2.042 0.051031
## CarNametoyota carina -2.391e+04 1.317e+04 -1.816 0.080555
## CarNametoyota celica gt -2.346e+04 1.333e+04 -1.760 0.089717
## CarNametoyota celica gt liftback -3.134e+04 1.247e+04 -2.514 0.018216
## CarNametoyota corolla -2.335e+04 1.249e+04 -1.869 0.072508
## CarNametoyota corolla 1200 -2.303e+04 1.217e+04 -1.891 0.069332
## CarNametoyota corolla 1600 (sw) -1.771e+04 1.227e+04 -1.444 0.160379
## CarNametoyota corolla liftback -2.306e+04 1.257e+04 -1.834 0.077633
## CarNametoyota corolla tercel -3.077e+04 1.251e+04 -2.460 0.020574
## CarNametoyota corona -2.340e+04 1.246e+04 -1.877 0.071343
## CarNametoyota corona hardtop -1.926e+04 1.268e+04 -1.519 0.140338
## CarNametoyota corona liftback -2.458e+04 1.242e+04 -1.980 0.058008
## CarNametoyota corona mark ii -2.379e+04 1.224e+04 -1.943 0.062558
## CarNametoyota cressida -1.740e+04 1.334e+04 -1.304 0.203348
## CarNametoyota mark ii -2.279e+04 1.251e+04 -1.822 0.079556
## CarNametoyota starlet -2.452e+04 1.236e+04 -1.984 0.057501
## CarNametoyota tercel -2.341e+04 1.272e+04 -1.840 0.076782
## CarNametoyouta tercel -2.016e+04 1.283e+04 -1.571 0.127776
## CarNamevokswagen rabbit -2.627e+04 1.464e+04 -1.794 0.083942
## CarNamevolkswagen 1131 deluxe sedan -2.754e+04 1.407e+04 -1.957 0.060719
## CarNamevolkswagen 411 (sw) -2.880e+04 1.415e+04 -2.035 0.051790
## CarNamevolkswagen dasher -2.524e+04 1.463e+04 -1.725 0.096003
## CarNamevolkswagen model 111 -2.715e+04 1.460e+04 -1.859 0.073938
## CarNamevolkswagen rabbit -2.160e+04 1.439e+04 -1.501 0.144961
## CarNamevolkswagen rabbit custom -2.239e+04 1.498e+04 -1.494 0.146687
## CarNamevolkswagen super beetle -2.496e+04 1.500e+04 -1.664 0.107693
## CarNamevolkswagen type 3 -2.843e+04 1.405e+04 -2.024 0.052989
## CarNamevolvo 144ea -2.480e+04 1.456e+04 -1.703 0.100031
## CarNamevolvo 145e (sw) -2.783e+04 1.408e+04 -1.976 0.058433
## CarNamevolvo 244dl -2.563e+04 1.427e+04 -1.795 0.083785
## CarNamevolvo 245 -2.271e+04 1.470e+04 -1.545 0.133964
## CarNamevolvo 246 -1.675e+04 1.529e+04 -1.095 0.283057
## CarNamevolvo 264gl -2.310e+04 1.443e+04 -1.600 0.121128
## CarNamevolvo diesel -2.006e+04 1.505e+04 -1.333 0.193567
## CarNamevw dasher -2.331e+04 1.526e+04 -1.528 0.138242
## CarNamevw rabbit -2.918e+04 1.469e+04 -1.987 0.057188
## fueltype -2.829e+04 1.147e+04 -2.467 0.020260
## aspirationturbo 7.218e+02 1.123e+03 0.643 0.525865
## doornumbertwo -8.107e+02 8.165e+02 -0.993 0.329562
## carbodyhardtop 1.878e+03 2.064e+03 0.910 0.370935
## carbodyhatchback 2.774e+03 1.266e+03 2.192 0.037208
## carbodysedan 3.530e+03 1.065e+03 3.314 0.002627
## carbodywagon NA NA NA NA
## drivewheelfwd 3.188e+01 1.466e+03 0.022 0.982814
## drivewheelrwd -4.916e+01 1.637e+03 -0.030 0.976263
## enginelocationrear 2.631e+03 3.928e+03 0.670 0.508619
## wheelbase 3.237e+02 1.483e+02 2.183 0.037936
## carheight -4.423e+02 3.123e+02 -1.416 0.168098
## curbweight 8.461e+00 3.824e+00 2.212 0.035588
## enginetypedohcv NA NA NA NA
## enginetypel NA NA NA NA
## enginetypeohc -4.588e+03 2.136e+03 -2.148 0.040816
## enginetypeohcf NA NA NA NA
## enginetypeohcv 1.076e+03 2.629e+03 0.409 0.685559
## enginetyperotor 6.013e+03 4.535e+03 1.326 0.195984
## cylindernumberfive NA NA NA NA
## cylindernumberfour 7.947e+03 2.436e+03 3.262 0.002996
## cylindernumbersix NA NA NA NA
## cylindernumberthree NA NA NA NA
## cylindernumbertwelve NA NA NA NA
## cylindernumbertwo NA NA NA NA
## enginesize 1.059e+02 5.506e+01 1.924 0.064940
## fuelsystem2bbl -7.318e+00 2.790e+03 -0.003 0.997927
## fuelsystem4bbl NA NA NA NA
## fuelsystemidi NA NA NA NA
## fuelsystemmfi NA NA NA NA
## fuelsystemmpfi -1.533e+02 2.618e+03 -0.059 0.953758
## fuelsystemspdi -1.408e+03 3.697e+03 -0.381 0.706325
## fuelsystemspfi -1.408e+03 4.524e+03 -0.311 0.758018
## boreratio -3.658e+03 2.065e+03 -1.771 0.087790
## stroke -1.066e+03 1.232e+03 -0.865 0.394512
## compressionratio -2.268e+03 8.801e+02 -2.577 0.015753
## horsepower -6.906e+01 3.809e+01 -1.813 0.080955
## peakrpm 4.557e+00 1.064e+00 4.284 0.000208
## citympg 2.462e+02 2.563e+02 0.960 0.345412
## highwaympg -4.603e+01 1.868e+02 -0.246 0.807266
## LxW -6.276e-01 8.857e-01 -0.709 0.484676
##
## (Intercept)
## car_ID .
## symboling
## CarNamealfa-romero Quadrifoglio
## CarNamealfa-romero stelvio
## CarNameaudi 100 ls
## CarNameaudi 100ls
## CarNameaudi 4000 .
## CarNameaudi 5000 .
## CarNameaudi 5000s (diesel)
## CarNameaudi fox
## CarNamebmw 320i
## CarNamebmw x1 **
## CarNamebmw x3 **
## CarNamebmw x4 **
## CarNamebmw x5 ***
## CarNamebmw z4 **
## CarNamebuick century
## CarNamebuick century luxus (sw)
## CarNamebuick century special
## CarNamebuick electra 225 custom
## CarNamebuick opel isuzu deluxe
## CarNamebuick regal sport coupe (turbo)
## CarNamebuick skyhawk
## CarNamebuick skylark
## CarNamechevrolet impala
## CarNamechevrolet monte carlo
## CarNamechevrolet vega 2300
## CarNamedodge challenger se
## CarNamedodge colt (sw) .
## CarNamedodge colt hardtop *
## CarNamedodge coronet custom *
## CarNamedodge coronet custom (sw) .
## CarNamedodge d200 *
## CarNamedodge dart custom
## CarNamedodge monaco (sw) .
## CarNamedodge rampage .
## CarNamehonda accord .
## CarNamehonda accord cvcc .
## CarNamehonda accord lx *
## CarNamehonda civic
## CarNamehonda civic (auto)
## CarNamehonda civic 1300 .
## CarNamehonda civic 1500 gl
## CarNamehonda civic cvcc
## CarNamehonda prelude *
## CarNameisuzu D-Max
## CarNameisuzu D-Max V-Cross
## CarNameisuzu MU-X *
## CarNamejaguar xf
## CarNamejaguar xj
## CarNamejaguar xk
## CarNamemaxda glc deluxe
## CarNamemaxda rx3
## CarNamemazda 626 .
## CarNamemazda glc
## CarNamemazda glc 4
## CarNamemazda glc custom
## CarNamemazda glc custom l *
## CarNamemazda glc deluxe
## CarNamemazda rx-4 .
## CarNamemazda rx-7 gs
## CarNamemazda rx2 coupe
## CarNamemercury cougar
## CarNamemitsubishi g4 *
## CarNamemitsubishi lancer *
## CarNamemitsubishi mirage *
## CarNamemitsubishi mirage g4 *
## CarNamemitsubishi montero *
## CarNamemitsubishi outlander *
## CarNamemitsubishi pajero *
## CarNamenissan clipper
## CarNamenissan dayz .
## CarNamenissan fuga
## CarNamenissan gt-r *
## CarNamenissan juke
## CarNamenissan kicks
## CarNamenissan latio .
## CarNamenissan leaf
## CarNamenissan note
## CarNamenissan nv200 .
## CarNamenissan otti .
## CarNamenissan rogue .
## CarNamenissan teana
## CarNamenissan titan
## CarNameNissan versa .
## CarNamepeugeot 304 **
## CarNamepeugeot 504 **
## CarNamepeugeot 504 (sw) **
## CarNamepeugeot 505s turbo diesel **
## CarNamepeugeot 604sl **
## CarNameplymouth cricket .
## CarNameplymouth duster *
## CarNameplymouth fury gran sedan *
## CarNameplymouth fury iii *
## CarNameplymouth satellite custom (sw) *
## CarNameplymouth valiant
## CarNameporcshce panamera
## CarNameporsche boxter
## CarNameporsche cayenne
## CarNameporsche macan
## CarNamerenault 12tl .
## CarNamerenault 5 gtl *
## CarNamesaab 99e
## CarNamesaab 99gle
## CarNamesaab 99le .
## CarNamesubaru *
## CarNamesubaru baja *
## CarNamesubaru brz *
## CarNamesubaru dl *
## CarNamesubaru r1 *
## CarNamesubaru r2 *
## CarNamesubaru trezia *
## CarNamesubaru tribeca .
## CarNametoyota carina .
## CarNametoyota celica gt .
## CarNametoyota celica gt liftback *
## CarNametoyota corolla .
## CarNametoyota corolla 1200 .
## CarNametoyota corolla 1600 (sw)
## CarNametoyota corolla liftback .
## CarNametoyota corolla tercel *
## CarNametoyota corona .
## CarNametoyota corona hardtop
## CarNametoyota corona liftback .
## CarNametoyota corona mark ii .
## CarNametoyota cressida
## CarNametoyota mark ii .
## CarNametoyota starlet .
## CarNametoyota tercel .
## CarNametoyouta tercel
## CarNamevokswagen rabbit .
## CarNamevolkswagen 1131 deluxe sedan .
## CarNamevolkswagen 411 (sw) .
## CarNamevolkswagen dasher .
## CarNamevolkswagen model 111 .
## CarNamevolkswagen rabbit
## CarNamevolkswagen rabbit custom
## CarNamevolkswagen super beetle
## CarNamevolkswagen type 3 .
## CarNamevolvo 144ea
## CarNamevolvo 145e (sw) .
## CarNamevolvo 244dl .
## CarNamevolvo 245
## CarNamevolvo 246
## CarNamevolvo 264gl
## CarNamevolvo diesel
## CarNamevw dasher
## CarNamevw rabbit .
## fueltype *
## aspirationturbo
## doornumbertwo
## carbodyhardtop
## carbodyhatchback *
## carbodysedan **
## carbodywagon
## drivewheelfwd
## drivewheelrwd
## enginelocationrear
## wheelbase *
## carheight
## curbweight *
## enginetypedohcv
## enginetypel
## enginetypeohc *
## enginetypeohcf
## enginetypeohcv
## enginetyperotor
## cylindernumberfive
## cylindernumberfour **
## cylindernumbersix
## cylindernumberthree
## cylindernumbertwelve
## cylindernumbertwo
## enginesize .
## fuelsystem2bbl
## fuelsystem4bbl
## fuelsystemidi
## fuelsystemmfi
## fuelsystemmpfi
## fuelsystemspdi
## fuelsystemspfi
## boreratio .
## stroke
## compressionratio *
## horsepower .
## peakrpm ***
## citympg
## highwaympg
## LxW
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## Residual standard error: 1267 on 27 degrees of freedom
## Multiple R-squared: 0.9967, Adjusted R-squared: 0.9748
## F-statistic: 45.64 on 177 and 27 DF, p-value: < 2.2e-16plot(model2)## Warning: not plotting observations with leverage one:
## 1, 2, 3, 4, 6, 8, 9, 10, 13, 15, 16, 17, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 34, 36, 37, 39, 40, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 59, 61, 62, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 86, 87, 90, 91, 94, 95, 96, 98, 101, 102, 103, 104, 105, 106, 109, 110, 115, 120, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 143, 144, 145, 146, 147, 148, 151, 154, 155, 156, 166, 167, 168, 171, 173, 175, 182, 183, 184, 185, 186, 187, 188, 190, 191, 192, 193, 198, 200, 204
## Warning in sqrt(crit * p * (1 - hh)/hh): NaNs produced## Warning in sqrt(crit * p * (1 - hh)/hh): NaNs produced
Conclusion
The second plot including the binomial and the quadratic is actually less accurate and the Q-Q plot shows the data is not distributed normally, however we have strong R2 values. I would think with some normalization we could eventually utilize a strong linear model.