Flashcards in Central Tendency- Mean, Median, and Mode ( Chapter 4) Deck (6)
How is the mean calculated and what does it look like?
1. Add up all the scores
2. Divide the total of the scores by the number of scores .
3. The formula looks like M= sum of observations (x-bar) divided by the number of observations
4. The sample is M or x-bar; the population is mew (small cursive m)
How do you calculate the middle score?
1. Line up scores in ascending order ( first to last)
2. Find the middle score ( odd # of scores, there will be 1 middle score; even # of scores, there will be 2 middle scores. Count the scores and divide by 2 then add 0.5.
3. Count across that specific number of scores. That number is the middle score
For even scores, use same method as above but after adding 0.5, the median is the mean of the two.
How do you calculate the mode?
The mode is the most common score; the SCORE that occurs most frequent--not the # of times it occurs
How do you calculate the range?
Subtract the lowest score from the highest score. It looks like X (highest)- X (lowest)=
How do you calculate variance and what does it look like?
1. Subtract the mean from every score
2. Square every deviation from the mean (squared deviations)
3. Sum all of the squared deviations
4. Divide the sum of the squares by the total number in the sample