levels of measurement

definition: levels of measurement

the way data has been measured within a study. they signify both the type of data that has been collected and how sophisticated/complex the data is

what are the 4 levels of measurement

nominal, ordinal, interval, ratio

what is nominal as a level of measurement

shows categories of data represented by frequencies. the data sets have no relative numerical value. named and labelled.

what is ordinal as a level of measurement

data can be placed into ascending or descending order, but the intervals between data are not necessarily equal. represents a position or rank in a sequence.

what is interval as a level of measurement

it has equal numerical intervals between scores. it lacks an absolute zero. could be negative.

what is ratio as a level of measurement

it has equal numerical intervals between scores. it has an absolute zero. can’t go negative.

examples of nominal

gender, religion, eye colour, court verdict

examples of ordinal

order finishing a race, ranking scale from strongly disagree to strongly agree, words recalled out of ten

examples of interval

temperature, IQ score, money in bank

examples of ratio

height, weight, distance travelled, heart rate

explain the level of measurement BEHAVIOURAL CATEGORY CHECKLIST will produce

nominal

what level of measurement CLOSED QUESTIONS will produce

nominal

explain what level of measurement SCALES will produce

ordinal

explain what level of measurement EVENT/TIME SAMPLING would produce

interval

explain what level of measurement CORRELATIONS will produce

ORDINAL AND ABOVE e.g. whether measuring negative values

what is the level of measurement for loftus and palmer ( ex 1 and 2) why, and provide a finding

experiment 1 is ordinal as it is an estimate of speed rather than definite. e.g. participants gave 40.8mph for smashed. experiment 2 is nominal data as the participants were asked if they saw any glass- yes or no.

what is the level of measurement for bowlby, why, and provide a finding

interval, measured IQ score, the range was 85-114

measure of central tendency: definition

measures of central tendency inform us of the central or middle values for a set of data. they are averages and give us a typical value for a set of data

mean: definition

the average that is shown by all scores in the data set when they are divided by n

mode: definition

the most common value within a set of data

median: definition

the mid point in a set of data that has been placed in order

what is the level of measurement for the MEAN

interval, ratio, ordinal

what is the level of measurement for the MODE

nominal, ordinal, interval, ratio

what is the level of measurement for the MEDIAN:

ordinal, interval, ratio

why is the median not nominal

because the median can be a calculated answer- doesn’t already exist as part of the data set

what are 2 strengths of using the mean

it is necessary for further statistical analysis such as standard deviation. it can always be found when using ordinal or above level data

what are 3 strengths of using the mode

can be used for data measured on a nominal scale. not a ‘nonsense’ value as the value has definitely occurred in the data set. it is not influenced by anomalous results

what are 2 strengths of using the median

not influenced by anomalous results. it can always be found when using ordinal or above level data

2 weaknesses of using the mean

influenced by anomalous results. it may produce a 'nonsense value- not in the original data set

2 weaknesses of using the mode

may be more than one result or no result if the data set is varied. may not display what is occurring in the centre of the data set if there is a skewed distribution

2 weaknesses of using the median

not useful in further statistical analysis. may produce a nonsense value- not in the original data set