data analysis : graphs

Question 1

what is the form of summary table used for ?

Answer 1

a way of representing data

Question 2

what is the summary table not merely but instead ?

Answer 2

raw scores but have been converted to descriptive statistics

Question 3

what is standard practice to include beneath the table ?

Answer 3

a summary paragraph explaining the results

Question 4

define bar charts

Answer 4

a type of graph in which the frequency of
each variable is represented by the height of the bars

Question 5

what can data be represented ?

Answer 5

visually using a suitable graphical display so the difference in mean values can be easily seen

Question 6

when are bar charts used ?

Answer 6

when data is divided into categories
–> known as discrete data

Question 7

what occupy the horizontal x-axis ?

Answer 7

the categories of the two conditions (typically CV)

Question 8

what is plotted in the y-axis ?

Answer 8

the frequency or amount of each category (typically DV)

Question 9

what are bars on a bar chart ?

Answer 9

separated on a bar chart to denote that we are dealing with separate
conditions

Question 10

define scattergram

Answer 10

a type of graph that represents the
strength and direction of a relationship between
co-variables in a correlational analysis

Question 11

what do scattergrams depict between covariables and not ?

Answer 11

they don’t depict differences but rather association

Question 12

where do the covariables have to lie ?

Answer 12

either x-axis or y-axis it doesn’t matter where

Question 13

what does each point on the graph correspond to ?

Answer 13

it corresponds to to the x position and y position of the co-variables

Question 14

what must a table and graph always have ?

Answer 14

a title and clearly label columns or axes

Question 15

what do the bars do in a histogram and why ?

Answer 15

touch each other
–> as it shows that data is continuous

Question 16

what is the x-axis made up of ?

Answer 16

equal -sized intervals of a single category

Question 17

what does the y-axis represent ?

Answer 17

the frequency within each intervals

Question 18

what would happen if there was zero frequency for one of the intervals ?

Answer 18

the interval remains but without a bar

Question 19

what type of data does line graphs represent ?

Answer 19

continuous data

Question 20

how are points used in line graphs ?

Answer 20

they are connected by lines to show how something changes in value

Question 21

what is plotted within the x-axis in a line graph ?

Answer 21

the IV

Question 22

what is plotted within the y-axis in a line graph ?

Answer 22

the DV

Question 23

define normal distribution

Answer 23

a symmetrical spread of frequency
data that forms a bell-shaped pattern. -the mean, median
and mode are all located at the highest peak

Question 24

give an example of normal distribution in everyday life and what does that mean ?

Answer 24

the height of all the people in your
school/college
–> should form a bell-shaped curve
–> most people are located in the middle area of the curve
–> very few people at the extreme ends

Question 25

the normal distribution is …

Answer 25

symmetrical

Question 26

what does the ‘tails’ of the curve do ?

Answer 26

extend outwards and never touch the horizontal x-axis (never reaches 0)

Question 27

why does the ‘tails’ of the curve do this ?

Answer 27

as more extreme scores are always theoretically possible

Question 28

define skewed distribution

Answer 28

a spread of frequency data that is
not symmetrical, where the data clusters to one end

Question 29

what do skewed distributions do ?

Answer 29

distributions that appear to lean to one side or the other

Question 30

define positive skew

Answer 30

–a type of distribution in which the long tail is on the positive (right) side of the peak and most of the distribution is concentrated on the left

Question 31

give an example of positive skew

Answer 31

a very difficult test in which most people got low marks with only a handful of students at the
higher end
–> this would produce a positive skew

Question 32

what affects the normal distribution ?

Answer 32

the mean

Question 33

what affects the normal distribution a lot less or not all ?

Answer 33

the mode and the median

Question 34

give an example of negative skew

Answer 34

a very easy test would produce
a distribution where the bulk of the scores are concentrated on the right
–> resulting in a long tail of anomalous scores on the left

Question 35

what order does the mean mode and median go in for negative skew ?

Answer 35

left to right
mean –> median –> mode

Question 36

what order does the mean mode and median go in for positive skew ?

Answer 36

left to right
mode –> median –> mean

Question 37

define negative skew

Answer 37

a type of distribution in which the long tail is on the negative (left) side of the peak and most of the
distribution is concentrated on the right