Data Analysis: Graphs Flashcards
What is a bar chart and when is it used
-type of graph in which the frequency of each variable is represented by the height of the bars
-used when data is divided into categories(discrete)
What is a scattergram and what does it show
-type of graph that represents the strength and direction of a relationship between co-variables in a correlational analysis
What is a histogram and when is it used
-bars touch each other, x-axis made up of equal sized intervals of a single category and y-axis represents the frequency within each interval
-used when data is continuous
What is a line graph
-represents continuous data and uses points connected by lines to show how something changes in value as a variable changes
Where do IV and DV go on a line graph
-IV on x-axis
-DV on y-axis
What is normal distribution
When there is a symmetrical spread of frequency data that forms a bell-shaped pattern.
-tails of curve which extend outwards never touch the horizontal axis
Where are the mean, median and mode located on normal distribution graph
-all located at the highest peak of the graph
What is skewed distribution
-spread of frequency data that is not symmetrical as data clusters to one end
What is positive skew
Type of distribution in which the long tail is on the positive(right) side of the peak
Where are the mode, median and mean in positive skew graph
Mode remains at highest point of peak, then median to the right of this and mean dragged furthest to the right
What is negative skew
Type of distribution in which the long tail is on the negative(left) side of the peak
Where are the mode, median and mean located in a negative skew graph
-mode still at peak of the graph, median to the left of this and mean pulled furthest to the left
Why are graphs used
They provide a way to visually represent data so that trends can be identified
Why are statistics used
Allow us to make sense of and interpret large amounts of information
What is probability
Numerical measure of the likelihood that certain events will happen