Stats

Question 1

Mode

Answer 1

Number that appears the most

Question 2

Mean

Answer 2

Average. Determined by: sum of the terms / number of terms

Question 3

Median

Answer 3

Middle number in ordered set. Determined by n+1/2.
(n is sample size/number of digits)

Question 4

n

Answer 4

sample size/number of digits

Question 5

Quartiles

Answer 5

divides data set into quarters. data must be ordered.

Question 6

Q2 =

Answer 6

median

Question 7

interquartile range

Answer 7

the difference between Q3 and Q1

Question 8

range

Answer 8

Simplest measure of spread. Cannot be used for grouped frequency table. Affected greatly by outliers

Question 9

Outlier

Answer 9

an extreme value in the data set: significantly larger/smaller

Question 10

how to identify an outlier?

Answer 10

If value < Q1 - (1.5 x IQR)
or value > Q3 + (1.5 x IQR)

Question 11

Lower quartile formula?

Answer 11

n+1 / 4

Question 12

Upper quartile formula?

Answer 12

3(n+1) / 4

Question 13

What is Σ?

Answer 13

Sigma. Means ‘sum of’

Question 14

5 Number summary consists of?

Answer 14

1. min value
2. Q1
3. Q2 / Median
4. Q3
5. max value

Question 15

cumulative frequency

Answer 15

running total

Question 16

An ogive should be in an _____ shape.

Answer 16

S

Question 17

what do ogives illustrate?

Answer 17

cumulative frequency

Question 18

what is standard deviation?

Answer 18

• how far typical data values deviate from the average/mean
• the larger the distance is compared to the st dev, the more extreme the observation
• σ

Question 19

what is variance?

Answer 19

• the square of the standard deviation
• σ²

Question 20

what does it mean if data is negatively / left skewed?

Answer 20

mean < median

Question 21

what does it mean if data is positively / right skewed?

Answer 21

mean > median

Question 22

How do you graphically represent a five number summary?

Answer 22

box and whiskers plot

Question 23

describe a box and whiskers plot

Answer 23

end of left whisker: min value
left of box: Q1
middle of box: Q2
right of box: Q3
end of right whisker: max value

can help to draw a number line underneath