Chapter 2

Question 1

percentile

Answer 1

the percent of data less than or equal to a certain data value

Question 2

z-score (definition)

Answer 2

how many standard deviations a data point is above/below the mean

Question 3

z-score (formula)

Answer 3

data point minus mean over standard deviation

Question 4

positive z-score

Answer 4

above the mean, data value greater than mean

Question 5

negative z-score

Answer 5

below the mean, data value less than mean

Question 6

adding or subtracting every data value by a constant

Answer 6

center-add/subtract by constant
spread-same
shape-same

Question 7

multiplying or dividing every data value by a constant

Answer 7

center-multiply/divide by constant
spread-multiply/divide by constant
shape-same

Question 8

the normal curve

Answer 8

symmetric, unimodal, bell shaped, mean=median

Question 9

the empirical rule

Answer 9

within one standard deviation on either side of the mean is 68% of the data, 2 standard deviations 95%, 3 standard deviations 99.7%

Question 10

empirical rule intervals (min -3, -3 -2… 3 max)

Answer 10

0.15, 2.35, 13.5, 34, 34, 13.5, 2.35, 0.15

Question 11

normal curve problems

Answer 11

1. draw and label curve with mean, standard deviation, ticks
2. do calculations (SHOW WORK!)
3. answer the question with context

Question 12

mean of z-scores is…

Answer 12

always 0

Question 13

standard deviation of z-scores is…

Answer 13

always 1

Question 14

normalcdf

Answer 14

put in upper/lower bounds and mean/SD (0 and 1 for z-score, real numbers for real numbers) to get area/percentile

Question 15

invNorm

Answer 15

put in area (percentile, decimal) and mean/SD (0 and 1 for z-scores, real numbers for real numbers) to get equivalent z-score or x value