Descriptive statistics Flashcards
what level of data should the mean be used with?
interval
what level of data should the median be used with?
ordinal
what level of data should the mode be used with?
nominal
How do u calculate the mean?
-adding up all the scores and then dividing by the total number of scores
How do u calculate the mode?
-the most common value
How do u calculate the median?
-place the numbers in order and find the middle value
What are the advantages of calculating the mean?
-it is sensitive as it takes every value into account
What are the advantages of calculating the median?
-unaffected by outliers in one direction
What are the advantages of calculating the mode?
- shows what most participants scored
- unaffected by extreme scores
What are the disadvantages of calculating the mean?
-may not represent the general set of scores
What are the disadvantages of calculating the median?
- doesn’t take into account every score
- doesn’t work well with small data
What are the disadvantages of calculating the mode?
- cant be used for small data of there is no mode
- large sets of data may have many modes
When shouldn’t the mode be used?
when there are several scores that occur frequently
When shouldn’t the median be used?
when data is interval or nominal
When shouldn’t the mean be used?
when there are anomlis
give the definition of the term measure of central tendency
mathmatical way to describe a typical or average score from data set
howdo u calculate the mean?
largest value - smallest value
What level of data should the range be used with?
median
ie ordinal
What are the advantages of calculating the range?
-easy to calculate
What are the advantages of calculating the variance?
-takes into account all scores
What are the advantages of calculating standard deviation?
- takes into account all scores
- sensitive measure of dispersion
define the term measure of dispersion
describes the variation of spread in the scores in the data set, around the measure of central tendency
when should the range be used?
when the data is consistent and there are no extreme scores
when should the standard deviation be calculated?
when you wish to make a very sensitive measure of dispersion
What are the disadvantages of calculating the range?
easily distorted by extreme scores
What are the disadvantages of calculating standard deviation?
difficult to calculate compared with the mean
what does a large standard deviation indicate?
spread from the mean
what does a small standard deviation indicate?
clustered closely around the mean
what does a zero standard deviation indicate?
it is the mean
