Research Methods : Graphs And Distributions

Question 1

Rules when drawing a graph

Answer 1

Draw in pencil 
Ensure a title is present 
Axes should be labelled 
Provide a unit of measure
Ensure graph is plotted correctly - scale that does not leave graph paper left over

Question 2

Describe bar charts

Answer 2

Used for data that comes from categories
Categories- x axis frequency - y axis
Always space between categories because data is discrete

Question 3

Describe a histogram

Answer 3

For data that is related - tells us how they differ from bar charts
Bars of unequal length
Frequency density - y axis
Continuous data - x axis
No gap between categories - related to each other

Question 4

How do you draw a histogram ?

Answer 4

1) calculate the widths of the groups by subtracting two values
Eg if 20

Question 5

Describe a line graph

Answer 5

Uses continuous data
Frequency plotted on the y axis
Continuous data is plotted on the x axis
Allow more than one set of continuous data to be shown at one time

Question 6

Describe a scattergram

Answer 6

These show associations or relationships between co variables
For each individual two scores are obtained but only one dot is plotted
Scatter of dots indicate the degree of correlation between two variables

Question 7

How many degrees in a circle

Answer 7

360

Question 8

What does a pie chart represent

Answer 8

Percentage of different categories of that ‘thing’

Question 9

How do you draw a pie chart from a data

Answer 9

1) divide each frequency by the total frequency
2) then multiply by 360
3) this is the angle that needs to be plotted using protractor

Question 10

Describe a results table

Answer 10

A summary of data
Include discriptive statistics
Do not show raw data collected from research

Question 11

Describe a normal distribution

Answer 11

Shown as a bell curve
Most scores fall round the mean
Curves are symmetrical
Mean mode median should all fall at the same point

Question 12

The curves of the tail of a normal distribution….

Answer 12

Rarely touch the horizontal axis- but theoretically possible to have more extreme scores

Question 13

What are normal distributions linked to ?

Answer 13

Standard deviation

Question 14

What percentage of data lies within 1 standard of data

Answer 14

68.36%

Question 15

What are percentages that lie above and below the mean

Answer 15

34.13% for both

Question 16

What is the percentage that lies within 2 standard deviations

Answer 16

95.44%

Question 17

What is percentage that lies both above and and below the mean

Answer 17

47.72%

Question 18

When do skewed distributions occur

Answer 18

When distribution around the mean is not symmetrical

Mean is no longer in the middle

Question 19

Why does skewing occurs

Answer 19

Extreme results

Question 20

When is there a positive skew

Answer 20

There are more low scores in the data

Question 21

Describe a positive skew

Answer 21

Distribution concentrated towards left of the data
Extreme high score - long tail to the right
Mode the highest point
Mean gets pulled towards the extreme score
Median sits in the middle of mode and mean

Question 22

How do we decipher if it is a positive skew

Answer 22

If the mean or median are a higher larger number than the mode
The mean will be towards the right of the median

Question 23

Describe a negative skew

Answer 23

More high scores in the data
Distribution concentrated towards right of the graph
Low extreme scores - long tail to left
Mode - highest
Mean pulled to extreme data
Median sits in the middle of the mean and mode

Question 24

If scores are very similar to the mean and median is not in the middle off the mean and mode what kind of distribution would it be ?

Answer 24

A normal distribution since the scores fall around the mean and this will typically be a bell shape curve