Descriptive statistics

Question 1

Draw __ to check distribution of a continuous variable

Answer 1

Histogram

Question 2

Normal distribution is a probability distribution that is:

Answer 2

symmetric about the center

data near center are more frequent in occurance

a bell curve in graph form

Question 3

More data on the left tail than right

Answer 3

Skewed to the left

Question 4

More data on the left tail than right

Answer 4

Skewed to the right

Question 5

Suggestive of two different populations

Answer 5

Bimodal

Question 6

Most common value for central tendency

not good for data with an outlier or skewed distribution

Answer 6

Mean

Question 7

value in the middle of a ranked data

better for data with an outlier or skewed distribution

Answer 7

Median

Question 8

value that occurs most often

highest bar on histogram

rarely reported for continuous data

Answer 8

Mode

Question 9

if mode > median > mean

Answer 9

data skewed to right

Question 10

if mean > median > mode

Answer 10

data skewed to left

Question 11

Range

Answer 11

maximum - minimum
or as interval (min, max)

common measure for spread of data around median

can be misleader in data with outlier

Question 12

Interquartile range (IQR)

Answer 12

Q3-Q1 or (Q1, Q3)
where:
Q1= value that occurs at 1st quarter mark
Q2= value that occurs at 2nd quarter mark (median)
Q3= value that occurs at 3rd quarter mark

Measures better than range for data with outlier

Question 13

If you count the numbers in each category of a table you are measuring:

Answer 13

Frequency

Question 14

If you find the % of each category of a table you are measuring:

Answer 14

Proportion

Question 15

Charts for continuous data

Answer 15

Histogram and Box plot

Question 16

Charts for categorical data

Answer 16

Pie graph and bar graph