PYC4807 PSYCHOLOGICAL ASSESSMENT DEFINITIONS CHAPTERS 3

PYC4807 PSYCHOLOGICAL ASSESSMENT DEFINITIONS CHAPTERS 3 MEASURE OF CENTRAL TENDENCY - CORRECT ANSWERS Mean, median, and mode. They are used to organise and summarise a set of data. = numerical values that best reflect the centre of a distribution of scores @tells us about how high/low on average a group or individual scored in a measure MEAN - CORRECT ANSWERS the arithmetic average of a distribution - average of the expectation of data = obtained by adding the scores and then dividing by the number of scores #tells us about data as a whole and not about individual data points #Good at measuring things that are nomrally distributed NORMAL - CORRECT ANSWERS =a distribution of data that has roughly the same amount of data on either side of the middle =most common values around the middle of the data DISTRIBUTION - CORRECT ANSWERS -the arrangement of data =shows how often each value occurs in a data set FREQUENCY - CORRECT ANSWERS =how often each value occurs in the data set NORMAL DISTRIBUTION - CORRECT ANSWERS =describes a symmetrical bell shaped curve that shows the distribution of many physical and psychological attributes MEDIAN - CORRECT ANSWERS =the middle score in a distribution =half the scores are above it and half are below it =middle number if we line up our data from smallest to largest MODE - CORRECT ANSWERS =the most frequently occurring score(s) / value in a distribution #most popular value BIMODAL DATA - CORRECT ANSWERS =a histogram will have two peaks as the data has two modes = like a camel's back = example of MULTIMODAL DATA *has many values that are similarly common #usually results from 2 or more underlying groups all being measured together NORMALLY DISTRIBUTED - CORRECT ANSWERS = represents the distribution of variables as a symmetrical bell-shaped graph. =distributions of scores where most people score in the area of the mean (average) #fewer people achieve at the extremely high/low tails of the distribution SKEWED - CORRECT ANSWERS =turned to one side =slanting =distorted #when mean and median is differently distributed #this means that there are usually extreme values on one side of our distribution large or small in our data set NEGATIVELY SKEWED - CORRECT ANSWERS #a distribution of scores in which scores are concentrated in the high end of the distribution =test was easy *many people answered correctly POSITIVELY SKEWED - CORRECT ANSWERS #a distribution of scores in which scores are concentrated in the low end of the distribution =test was difficult *many people answered incorrectly HIGH MODE - CORRECT ANSWERS =values that are high in the data set LOW MODE - CORRECT ANSWERS =values that are low in the data set MEASURES OF SPREAD - CORRECT ANSWERS =Range =Interquartile Range =Standard Deviation DISPERSION - CORRECT ANSWERS =the pattern of spacing among individuals within the boundaries of the population =tells us how data is spread around the middle of the distribution =lets us know how well the mean and median represents the data =how much we trust conclusions on the mean and median RANGE - CORRECT ANSWERS Distance between highest and lowest scores in a set of data @takes the largest number in our data set and subtracts the smallest number in the set to give us the distance between these 2 extremes =the larger the difference the more spread out our data