Chapter 2

Question 1

What is the frequency compared to the relative frequency?

Answer 1

Frequency is the exact number of items in that category while the relative frequency is the frequency divided by the total (percent)

Question 2

What’s the difference between a bar graph and a histogram?

Answer 2

A histogram has all the bars touching

Question 3

What is a grouped frequency distribution table?

Answer 3

Where you sort all the data given into group or classes on a chart
Ex: take all marks in the class and sort them into groups of percents like 0-10, 10-20, 20-30, etc. And tally them up

Contains tally, frequency, relative frequency and percentage

Question 4

What is an outlier?

Answer 4

An observation that lies outside the overall pattern of distribution

A large gap in distribution is usually a sign of an outlier

Question 5

What do you do when you get outliers?

Answer 5

If you can go and recollect the data again then do it

If not, use robust statistical methods where outliers do not affect the results as much

Question 6

What are dot plots?

Answer 6

Essentially bar graphs except it uses dots for each number going up
Each dot represents a quantity

Question 7

What are the three steps to making a stem plot?

Answer 7

1. Separate each observation into a stem, made up of left side digits, and a leaf made up of right side digits
2. Write the stems in a vertical column with the smallest value at the top, and draw a vertical line at the right of this column
3. Write each leaf in the row to the right of its stem, in increasing order out from the stem
   (Review in notes)

Question 8

What do you do for negatives in stem plots?

Answer 8

They go at the top but everything is reverse since a higher negative number is less than a lower negative number!