2.2
What are the mode distribution for ordered data?
1) Unimodal- one mode 2) bimodal- 2 modes 3) uniform- mode not helpful 4)multimodal- more than two modes
What are the two factors guide choice of measure for summarizing data?
1) level of measurement 2) shape of distribution
What to do if there is a odd number of data points for median?
1) put points in order 2) count the points 3) median is the value of item at (n+1)/2= the number that is counted of the points EXAMPLE: if there are five different numbers then the median is the 3rd one
What to do if there is a even number of data points for median?
1) put points in order 2) count the points 3)take points surrounding (n+1)/2 4) median is the midpoint of these two points (can be a decimal point)
What are the properties of the mean?
1) use all of the values in the data 2)best for interval and ration scales 3) best when shape of the distribution for interval/ratio variable is symmetrical and unimodal
Mode is the best measure of central tendency for which type of data?
Nominal variables (complement with frequencies of each category) --> EXAMPLE: self-reported employment in n=500 UNLV students
What is mean?
average-->sum of all scores/number of scores mean is the arithemetic center of a distribution AKA the balance point of a distribution
What is central tendency
summarize the middle or most typical values for a variable such as mode, median, and mean
What is median?
the middle value in a frequency distribution ---> in a cumulative frequency table, the median is the point at the 50th percentile --half of measurements are below it, and half are above
What is mode?
the most common value of the variable
What is multiple peaks?
there are sub-groupings in the sample, and you could consider separating them for further analyses