Data Distribution in Research

Multiple Choice

The mean is found by ___________________ all of the numbers and then _____________________ by the number of items.

• adding, subtracting

• adding, multiplying

• dividing, adding

• adding, dividing

Multiple Choice

The median is the __________________ number (after you put them in order).

• first

• middle

• last

• one you see most

Multiple Choice

The _______________________ is the number that occurs most often in a data set.

• Mean

• Median

• Mode

• IQR

Multiple Choice

The _______________________ is what you get when you subtract the lowest value from the highest.

• Range

• IQR

• Q3

• Q1

Multiple Choice

In a data display, this is a break, space, or opening between values where no value occurs.

• gap

• black hole

• symmetric

• peak

Multiple Choice

An indication of a data display that shows where the data is at its highest point.

• cluster
• gap
• peak
• outlier

Multiple Choice

Describing the shape of a data set that has the same values across the entire display.

• symmetric

• unimodal

• skewed

• uniform

​Correlation

​Two sets of data can have a relationship called correlation. It can be positive or negative.

• Positive Correlation - the values  INCREASE  together.

​

• Negative Correlation - when one value INCREASES the other DECREASES.

​

• Linear Correlation - the correlation resembles a LINE.

​Correlation Coefficient (r)

Correlation Coefficient ​(r) describes the strength and direction of the correlation.

​

​r values can not be less than -1 or greater than +1. This can be written as the inequality  -1 < r < 1

Multiple Choice

Which value of r represents data with a strong negative correlation between two data sets?

• -1.07

• -0.89

• -0.14

• 0.92

Multiple Choice

Average time spent listening to music per day and average time spent watching TV per day.  $$r=-.17$$  

• strong positive

• strong negative

• weak positive

• weak negative

Multiple Choice

Number of steps taken per day and number of kilometers walked per day. $$r=.92$$  

• strong positive

• strong negative

• weak positive

• weak negative

Multiple Choice

Car weight and distance traveled using a full tank of gas.  $$r=-.86$$  

• strong positive

• strong negative

• weak positive

• weak negative

Multiple Choice

A study compared the number of years of education and a person's annual salary. The correlation coefficient of the data was r = 0.913. Which conclusion can be made using the correlation coefficient?

• There is a strong positive correlation.

• There is a strong negative correlation.

• There is no correlation.

• There is a weak positive correlation.

Multiple Choice

Test scores vs. shoe sizes

• Positive Correlation

• Negative Correlation

• No Correlation