Data Terms
Which of the following is a statistical question?
a) When is Halloween?
b) How many pieces of candy did you get?
c) What house has the best decorations?
d) How many students dressed up in each class?
d) "How many students dressed up in each class?" is a statistical question because it would generate more than one piece of numerical data.
Find the mode of the following data:
Number of Houses Visited By Trick-or-Treaters: 24, 15, 0, 21, 15, 10, 14, 10, 8, 12, 37.
The mode is 10 houses AND 15 houses. It's bi-modal!
How many observations were made in the data displayed by the dot plot in figure 1?
The dot plot shows 16 observations.
According to the histogram in Fig. 2, how many times did a car with a speed of 130-139 miles per hour win the Dayton 500?
Four cars have won the Dayton 500 with speeds between 130-139 mph.
What is the median weight of a medium-to-large dog according to the box plot in fig. 3?
The median weight is 54 kg.
What are the two most common measures of center?
Mean and median are the most common measures of center.
Find the range of the following data:
Math Test Scores: 90, 83, 98, 74, 84, 77, 69, 92
The range is 29 points.
What does each x represent in the dot plot in figure 1?
Each dot represents one PE student.
Which speed interval (group) was the mode in the histogram on Fig. 2?
Speeds of 150-159 mph were the mode.
What is the range of weights shown in the box plot in fig. 3?
The dog weights have a range of 14 kg.
Range and interquartile range (IQR) are both considered measures of... what?
Range and interquartile range are both considered measures of variation.
Find the median of the following data:
Time Spent Studying: 60, 30, 15, 20, 15, 25, 0
The median is 20 minutes.
What is the shape of the data displayed on the dot plot in figure 1?
The data in figure 1 appears to be Uniform.
Based on the histogram in Fig. 2, what was the range of speeds for winners of the Daytona 500?
The exact range cannot be found using the histogram in Fig. 2.
What is the interquartile range seen in fig. 3 (box plot)?
The interquartile range is 4 kg.
What term is used to describe a data point that is far away from the rest of the data set and can often skew the data?
An outlier.
Find the median of the following data:
Money Spent on Costumes: 21, 16, 50, 0, 12, 24
The median is $18.50.
What is the range of the data displayed in figure 1?
The range is 6 beats per minute.
How many more winning cars are there in the 140-149 mph interval than in the 120-129 mph interval?
There are about 13 more cars in the third interval than there are in the first interval.
Describe the shape of the data in fig. 3 (box plot).
The box plot in fig. 3 is slightly skewed right. Some people may see it as symmetrical, though.
Both dot plots and histograms display data by making vertical stacks. These stacks show the amount of observations in each column, also known as... what?
The amount of observations in each column is also called the frequency.
Find the mean of the following data:
Temperatures in October: 65, 63, 70, 63, 61, 59
The mean, or average, temperature in October was 63.5 degrees.
What is the mean of the data displayed on the dot plot in figure 1?
The mean is about 81.6875
Describe the shape of the data in fig. 2 (histogram).
The histogram is bell-shaped, or symmetrical.
One data set that could be represented by the box plot in fig 3 is written below. What are all of the possible numbers x could be?
Data Set: 54, 63, 49, 51, 51, 55 and x.
Answer 1: If you have never made a box plot, it is ok to assume that x could be any number from 54 to 63.
Answer 2: If you HAVE made a box plot, you should find that x = 55.