week 3 presenting data

Question 1

univariate

Answer 1

one variable

Question 2

bivariate

Answer 2

2 variables

IV and DV

more than 2 relationships

Question 3

multivariate

Answer 3

more than 2 variables

complex relationships

Question 4

noise

Answer 4

not part of testing logic, but interferes with the tested variation and defines reliability of results

Question 5

where does the IV go on a graph

Answer 5

x-axis

Question 6

where does the DV go on a graph

Answer 6

y-axis

Question 7

where does noise go on a graph

Answer 7

error bars

Question 8

give an example of noise

Answer 8

individual differences

Question 9

discrete data

Answer 9

integer values, potentially values eg number of cars in car park

no fractions or decimals

Question 10

continuous data

Answer 10

infinitesimal, real numbers eg time, temp and height

can include fractions or decimals

Question 11

what is the general rule for freedom

Answer 11

more freedom = more versatile but less organized

Question 12

pie chart

Answer 12

continuous, ratio-scaled axis presented as a circle

can include discrete data shown as wedges/circular sectors

Question 13

pro of pie chart

Answer 13

relate parts/wedges to the whole

Question 14

cons of pie chart

Answer 14

limited to 2 sources of variation - no error bars

requires ratio-scales, but finite data to define beginning and end of circumference

Question 15

pro of bar chart

Answer 15

highlighting distance from 0 or baseline = constant value

highlight differences across groups or conditions = nominal

visualise groups and conditions

Question 16

cons of bar chart

Answer 16

no continuos X - one axis needs to be discrete

clutter with many scores

Question 17

pros of line chart

Answer 17

shows trends and relationship

as change in y…change in x

Question 18

cons of line chart

Answer 18

covariation - useless when multiple data points per x-value

less efficient for grouping than bars

Question 19

pros of scattergraph

Answer 19

covariation

visuals 2D measures, bivariate distribution

Question 20

cons of line graph

Answer 20

lacks structure

occlusion

free floating points - clutter

Question 21

what is aggregation by frequency

Answer 21

individual data points are grouped and summarized based on how often they occur within specific categories, intervals, or values

Question 22

steps for aggregation

Answer 22

1. define categories
2. count occurrence
3. summarise data eg frequency table - can work out %

Question 23

where does frequency go on a graph

Answer 23

y-axis

Question 24

binning

Answer 24

transform continuous data into discrete data by allocating the continuous data to intervals (bins)

Question 25

histogram

Answer 25

a bar chart using bins to display continuous data

Question 26

how does negative skew look in a histogram

Answer 26

left tail is lower

Question 27

when do you use a histogram

Answer 27

for frequency and probability density

Question 28

frequency density

Answer 28

frequency of data per equal interval = frequency/bin size

Question 29

probability density

Answer 29

probability of data per value

Question 30

cumulative sum or running total

Answer 30

sum of frequencies progressively

Question 31

what type of graph would you choose if both IV and DV were qualitative (nominal or ordinal)

Answer 31

bar chart

Question 32

how to show standard deviation on a graph

Answer 32

standard error bars

Question 33

how can you represent an assymetrical distribution

Answer 33

box and whisper plot

Question 34

where is the outcome on a bivariate distribution

Answer 34

y axis

Question 35

where is predictor on a bivariate distribution

Answer 35

x axis

Question 36

when are mean and median the same

Answer 36

when the same number of values occurs on either side of the mean

Question 37

what does it mean when the distance between minimum and the mean is smaller than the SD

Answer 37

the distribution is positively skewed