Data analysis :

Question 1

measures of central tendency :

Answer 1

• measure of the average value in a set of data

- mean, median and mode

Question 2

median

Answer 2

• less sensitive as not all scores included

- not affected by extreme scores

Question 3

mean

Answer 3

• distorted by extreme scores as all scores included

Question 4

mode

Answer 4

Most occurring , bi modal = two most occurring

Question 5

measures of dispersion

Answer 5

• spread of scores

- range and standard deviation

Question 6

range strengths and weaknesses

Answer 6

+ easy to calculate

- only takes into account two most extreme scores and this may not be representative of data set as a whole

Question 7

standard deviation

Answer 7

• how far scores deviate from the mean

Question 8

how can descriptive statistics be displayed ?

Answer 8

graphs, tables etc

Question 9

two types of distribution graphs

Answer 9

normal and skewed

Question 10

positive skew

Answer 10

peak is pointing left and long tail to right

• most distribution is to right
• eg: hard test and most pupils do bad

Question 11

negative skew

Answer 11

peak is pointing to right and long tail to left

• most distribution to left
• eg: easy test so pupils do well

Question 12

bar charts

Answer 12

discrete data

Question 13

scattergrams

Answer 13

shows correlations between co variables

Question 14

normal distribution graph

Answer 14

most people lie in the middle with few on extreme sides, mean, mode and median all occupy same mid point of graph.

Question 15

inferential statistics

Answer 15

• inferential statistics uses statistical tests which tell the psychologists whether the differences and relationships found are significant or not.
• this helps us decide whether to accept or reject null hypothesis

Question 16

descriptive statistics

Answer 16

• used to analyse data sets and identify trends

- refers to things like graphs tables (such measures as measures of central tendency and measures of dispersion)