chapter 2 (descriptive stats)

Question 1

proportion

Answer 1

number of cases in one response category of a variable divided by number of cases in all response categories of the variable.
# of cases in response category/# of cases in all response categories.
OR
f/n

Question 2

percentage

Answer 2

number of cases in a response category of variable divided by number of cases in all response categories of variable, with entire quantity multiplied by 100.
(# of cases in response category/# of responses in all categories) x 100
or
(f/n) x 100

Question 3

ratio

Answer 3

number of cases in one response category divided by number of cases in some other response category.
f1/f2

Question 4

rates

Answer 4

number of actual occurrences of some phenomenon or trait divided by the number of possible occurrences per some unit of time.
rate = f actual/ f possible

Question 5

intervals

Answer 5

response categories created to produce frequency distributions for interval-ratio variables.

Question 6

midpoints

Answer 6

the point exactly halfway between the upper and lower limits of an interval.
(upper limit + lower limit)/2

Question 7

stated limits

Answer 7

the intervals of a frequency distribution when stated as discrete response categories.

Question 8

real limits

Answer 8

the intervals of a frequency distribution when stated as continuous response categories.

Question 9

cumulative frequency

Answer 9

optional column in frequency distribution that displays the number of cases within an interval and all preceding intervals.

Question 10

cumulative percentage

Answer 10

optional column in frequency distribution that displays percentage of cases within an interval and all preceding intervals.