Fathom and MLB American League Top 75 Hitters

Fathom and MLB American League Top 75 Hitters

1.  Start Microsoft Excel. Open the file mlbal2001.xls on the disk provided. This data came from ESPN.COM and represents the 75 American League hitters who qualified for the batting title. Select the data by clicking and dragging the mouse from cell A1 to R76. This range of cells should now be highlighted. Copy the cells into memory by either CTRL-C or by selecting Edit –Copy from the menu bar.

2.  Minimize Excel and open Fathom ( the little gold ball icon) Click on a collection and drag it to the work area or select Insert-Collection (CTRL-L).

3.  With the collection activated ( frame showing) select Edit-Paste Cases. (see Figure A.

4.  To Rename the collection: double click on “collection 1” on the collection. A pop-up window will appear and change the name to AL-2001.

5.  Double click on collection and the inspector will open.

6.  Drag a graph onto your work area. Select the inspector and scroll down until you see the attribute HR. Drag the attribute HR to the graph and drop it on the x-axis. What you now see is a dot plot of the homeruns hit by the top 75 hitters in the AL. (figure B). Click on the down arrow on the Dot Plot and select Histogram (figure C). Try Box plot (Figure D) – notice 1 outlier

Figure A

Figure B Figure C Figure D Figure E

7.  The Percentile Plot shows that 60% of AL hitters hit 20 of fewer homeruns. (Figure E)

8.  The Normal Quantile Plot (figure F) plots z-scores associated with the percentile of each case if the data were normally distributed. – this means if the data are normal, the plot should show a straight line. The x-axis crosses at the mean of the distribution. What does the plot show about the homerun distribution? (note: this is also plot 6 on the TI83)

9. Try dropping other attributes on the x-axis. Are there any that are normally distributed?

Figure F

Looking for associations- Is there an association between batting average and the number of homeruns? How about the number of homeruns and strikeouts? Homeruns and RBI’s? There are a lot of questions you can ask about the data.

Figure G at the right shows a positive association between Homeruns and RBI’s. You simply have to drag the HR attribute from the inspector to the x-axis and RBI attribute to the y-axis.

Can you find a stronger association? Can you find a negative association? Can you explain the relationship between the number of homeruns and triples (3B)?

Figure G