Homework SourseRefer to the Buena School District bus data provided on the
Refer to the Buena School District bus data provided on the author\'s website. Is there a difference in the mean maintenance cost for the diesel versus the gasoline buses? Use the .05 significance level.
Maintenance
Type
X2
X5
329
Diesel
503
Diesel
505
Diesel
466
Gasoline
359
Gasoline
546
Diesel
427
Gasoline
474
Gasoline
382
Gasoline
422
Gasoline
433
Diesel
474
Gasoline
558
Gasoline
561
Diesel
357
Diesel
329
Diesel
497
Gasoline
459
Gasoline
355
Gasoline
489
Diesel
436
Gasoline
455
Diesel
514
Gasoline
503
Diesel
380
Diesel
432
Diesel
478
Diesel
406
Gasoline
471
Diesel
444
Diesel
493
Diesel
452
Diesel
461
Diesel
496
Diesel
469
Diesel
442
Diesel
414
Gasoline
459
Diesel
457
Diesel
462
Diesel
570
Diesel
439
Gasoline
369
Gasoline
390
Diesel
469
Gasoline
381
Diesel
501
Diesel
432
Gasoline
392
Diesel
441
Diesel
448
Diesel
468
Diesel
467
Gasoline
478
Diesel
515
Diesel
411
Gasoline
504
Gasoline
504
Diesel
392
Diesel
423
Diesel
410
Diesel
529
Gasoline
477
Diesel
540
Diesel
450
Diesel
390
Diesel
424
Diesel
433
Diesel
428
Diesel
494
Diesel
396
Gasoline
458
Diesel
493
Diesel
475
Gasoline
476
Diesel
403
Diesel
337
Gasoline
492
Diesel
426
Diesel
449
Gasoline
454.7735849
Mean Diesel
441.4814815
Mean Gasoline
| Maintenance | Type |
| X2 | X5 |
| 329 | Diesel |
| 503 | Diesel |
| 505 | Diesel |
| 466 | Gasoline |
| 359 | Gasoline |
| 546 | Diesel |
| 427 | Gasoline |
| 474 | Gasoline |
| 382 | Gasoline |
| 422 | Gasoline |
| 433 | Diesel |
| 474 | Gasoline |
| 558 | Gasoline |
| 561 | Diesel |
| 357 | Diesel |
| 329 | Diesel |
| 497 | Gasoline |
| 459 | Gasoline |
| 355 | Gasoline |
| 489 | Diesel |
| 436 | Gasoline |
| 455 | Diesel |
| 514 | Gasoline |
| 503 | Diesel |
| 380 | Diesel |
| 432 | Diesel |
| 478 | Diesel |
| 406 | Gasoline |
| 471 | Diesel |
| 444 | Diesel |
| 493 | Diesel |
| 452 | Diesel |
| 461 | Diesel |
| 496 | Diesel |
| 469 | Diesel |
| 442 | Diesel |
| 414 | Gasoline |
| 459 | Diesel |
| 457 | Diesel |
| 462 | Diesel |
| 570 | Diesel |
| 439 | Gasoline |
| 369 | Gasoline |
| 390 | Diesel |
| 469 | Gasoline |
| 381 | Diesel |
| 501 | Diesel |
| 432 | Gasoline |
| 392 | Diesel |
| 441 | Diesel |
| 448 | Diesel |
| 468 | Diesel |
| 467 | Gasoline |
| 478 | Diesel |
| 515 | Diesel |
| 411 | Gasoline |
| 504 | Gasoline |
| 504 | Diesel |
| 392 | Diesel |
| 423 | Diesel |
| 410 | Diesel |
| 529 | Gasoline |
| 477 | Diesel |
| 540 | Diesel |
| 450 | Diesel |
| 390 | Diesel |
| 424 | Diesel |
| 433 | Diesel |
| 428 | Diesel |
| 494 | Diesel |
| 396 | Gasoline |
| 458 | Diesel |
| 493 | Diesel |
| 475 | Gasoline |
| 476 | Diesel |
| 403 | Diesel |
| 337 | Gasoline |
| 492 | Diesel |
| 426 | Diesel |
| 449 | Gasoline |
Solution
> ttt <- read.csv(\"clipboard\",sep=\"\\t\")
> head(ttt)
X2 X5
1 329 Diesel
2 503 Diesel
3 505 Diesel
4 466 Gasoline
5 359 Gasoline
6 546 Diesel
> t.test(X2~X5,ttt)
Welch Two Sample t-test
data: X2 by X5
t = 1.0343, df = 50.64, p-value = 0.3059
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
-12.51152 39.09573
sample estimates:
mean in group Diesel mean in group Gasoline
454.7736 441.4815
Using the above result, there is not a difference in the mean maintenance cost for the diesel versus the gasoline . buses
