The players who had the most hits in each Major League Baseball season over the last twenty years are listed below.

Source: http://mlb.mlb.com/NASApp/mlb/mlb/stats_historical/mlb_historical_leaders.jsp?

What would be the stems for a stem-and-leaf plot for the above data?

Sample correct response: Students need to include the first two digits of each data element so that you have only a single digit to plot on the stem-and-leaf plot, so the stems would be:

16
17
18
19
20
21
22
23
24

What digits would be on the '24' line of the stem for the stem-and-leaf plot using the above data?

Sample Correct Response: The '24' line would include the digits 0, 0, and 2.

Create a stem-and-leaf plot to display the number of hits by the hits leader in each season.

Sample Correct Response:

The all time record for number of hits in one season was set in 2004, with 262 hits by Ichiro Suzuki of the Seattle Mariners. If 262 is added to the data set, how would this change the stem-and-leaf plot?

Sample correct response: If 262 is added to the data set, then you need to add 25 and 26 after 24 to the stem so that 262 can be added as 26 | 2.

There was a baseball strike in 1994 and the baseball season was shortened, so the total number of record hits is lower than other years (only 165). If there was another such strike and the record hits were only 148 hits, how would this change the stem-and-leaf plot?

Sample correct response: If 148 is added to the data set, then the stem would need to include both 14 and 15 before the 16 so that 14 | 8 could be added to the stem-and-leaf plot.

Create a stem-and-leaf plot to display the number of hits by the hits leader in each season.

Describe the data displayed in terms of

• Gaps in the data
• Minimum and maximum values
• Where most of the data is located
• Unusual data value(s)

Based on your description, in what stem do you think the average number of hits by the hit leader lies? Explain why your answer is correct. Use what you know about averages and stem-and-leaf plots in your explanation. Use words, data, and/or symbols in your explanation.

Sample Correct Response:
There is a gap in the data between 165 and 192. The minimum value is 165 and the maximum value is 242. Most of the data lies between 210 and 230. It seems to be clustered around 210 through 220. I would say that 165 is unusually low for this set of data because it is almost 30 to the next number, 192. I would predict that the mean is somewhere between 210 and 220 because that seems to be where almost half the data is.