Sample means, 54–55
calculation of, 54
explanation of, 54, 224–225
formula for, 54
sampling distribution of, 230–235
symbol for, 55
Sample median
calculation of, 56–58
explanation of, 56, 224
Sample point probabilities
calculation of, 185–187
explanation of, 119–122
Sample points
for coin-tossing experiment, 118
collection of, 121
for complex experiments, 124–126
explanation of, 117–119, 168
Sample size, 55
central limit theorem and, 452
determining, 458–459
method to determine, 399–401
population mean and, 282–284
population proportion and, 284–286
Sample space, 118–120
Sample standard deviation, 66
Sample variance, 66
Sample variance formula, 66
Sample z-score, 80
Samples
biased, 17, 18
explanation of,
random, 12
representative, 12
Sampling
cluster, 184
independent, 369–379, 451–455
lot acceptance, 220–221
Sampling distributions
central limit theorem and, 232–233
explanation of, 225
method to find, 226–227
of sample mean, 230–235
simulation of, 225
standard deviation of, 231
Sampling error
explanation of, 283
sample size to estimate difference between pair of parameters with specified, 399–400
SAS, linear regression on, 509, 520–521, 551–553
Scatterplots
explanation of, 93
normal probability plot as, 210
use of, 93–95, 506
Selection bias, 14, 18
Self-selection, 15
Sign test, 352–355
application of, 354–355
conditions required for valid application of, 354
explanation of, 352
large-sample sign test for a population mean, 354
Signed rank test. See Wilcoxon (paired difference) signed rank test
Significance, level of, 312
Significance levels, observed
explanation of, 318–322
method to find, 455
Skewness, 57, 58
Slope, 503
Small-sample inferences, 334
Small samples
conditions for inferences, 376, 391
population mean comparisons and, 374–379
Spearman, Charles E., 556
Spearman’s rank correlation coefficient, 555–557, 559
conditions required for a valid, 559
critical values of, 559
example of, 557–558
shortcut formula for, 556
Spread, 65. See also Variability
SPSS, linear regression on, 509, 526
Standard deviation
for binomial random variable, 189
of discrete random variable, 175–176
explanation of, 65–66
interpretation of, 71–74
sample, 66
of sampling distribution, 231
symbols for, 67
variability and, 71
Standard error of statistic, 371
Standard normal distribution, 197
Standard normal random variable
explanation of, 197
method to find, 198–201
Standard normal table
explanation of, 196–197
use of, 198–200
used in reverse, 204
Statistic, standard error of, 371
Statistical inference. See also Inferences; specific topics
example of, 74–75
explanation of,
numerical descriptive measures and, 54
Statistical test
elements of, 309
p-values and, 318–322
Statistical thinking, 17
Statisticians,
Statistics. See also Descriptive statistics; Inferential statistics; specific topics
applications of, –
explanation of, –
fundamental elements of, –
types of,
Stem-and-leaf display, 46
benefits and drawbacks of, 46
explanation of, 43–44, 48
Straight-line model
estimation using, 510–511, 519
explanation of, 501, 502
prediction using, 546
Stratified random sampling, 13
Sum of squares for treatments (SST), 423
Sum of squares of error (SSE), 423, 506, 507
Summation notation, 54
Surveys, 12, 15–18
Systematic sampling, 13