2-3(cont)_mean_sd_together

# 2-3(cont)_mean_sd_together - 2.3(cont Using the Mean and...

This preview shows pages 1–8. Sign up to view the full content.

1 2.3 (cont.) Using the Mean and Standard Deviation Together 68-95-99.7 rule z-scores

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
2 68-95-99.7 rule Mean and Standard Deviation (numerical) Histogram (graphical) 68-95-99.7 rule
3 The 68-95-99.7 rule; applies only to mound-shaped data approximately 68% of the measurements are within 1 standard deviation of the mean, that is, in ( , ) approx. 95% of the measurements are within 2 stand. dev. of the mean, i.e., in ( 2 , 2 ) almos y s y s y s y s - + - + t all the measurements are within 3 stan. dev of the mean, i.e., in ( 3 , 3 ) y s y s - +

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
68-95-99.7 rule: 68% within 1 stan. dev. of the mean 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 -5 -4.5 -4 -3.5 -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 68% 34% 34% y-s y y+s
5 68-95-99.7 rule: 95% within 2 stan. dev. of the mean 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 -5 -4.5 -4 -3.5 -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 95% 47.5% 47.5% y-2s y y+2s

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
6 Example: textbook costs 375.48 42.72 50 y s n = = = 286 291 307 308 315 316 327 328 340 342 346 347 348 348 349 354 355 355 360 361 364 367 369 371 373 377 380 381 382 385 385 387 390 390 397 398 409 409 410 418 422 424 425 426 428 433 434 437 440 480
7 Example: textbook costs (cont.) 286 291 307 308 315 316 327 328 340 342 346 347 348 348 349 354 355 355 360 361 364 367 369 371 373 377 380 381 382 385 385 387 390 390 397 398 409 409 410 418 422 424 425 426 428 433 434 437 440 480 375.48 42.72 ( , ) (332.76, 418.20) 32

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 02/13/2012 for the course BUS 350 taught by Professor Reiland during the Fall '08 term at N.C. State.

### Page1 / 18

2-3(cont)_mean_sd_together - 2.3(cont Using the Mean and...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online