QMM 240
TR 10:00-11:15
Computer Assignment #1 1. a. Excel Histograms Bins MPG | Frequency | 11 | 1 | 16 | 3 | 21 | 16 | 26 | 34 | 31 | 13 | 36 | 9 | 41 | 2 | 46 | 2 |
Bins Weight | Frequency | 1300 | 1 | 1780 | 7 | 2260 | 18 | 2740 | 12 | 3220 | 22 | 3700 | 11 | 4180 | 7 | 4660 | 2 | b. I chose the number of classes based on the Sturges’ Rule table. I knew I had 80 observations so that put me between either 7 or 8 classes. I chose 8 for both because that allowed the data to completely taper off at the very ends of the data; meaning the extremely low values were caught within the first and the last classes. I chose the width of the classes by taking the lowest value minus the highest value and then dividing that number by the amount of classes I intended on using. For example, in the MPG histogram I took 44 minus 11 and then divided by 8. That gave me about 4.13 so I rounded up to five to make all the numbers whole numbers. c. In the MPG histogram the central tendency is from 16 to 31. Over 78% of the data is within that range. This histogram is evenly distributed with an average “bell shaped curve”. This histogram is also evenly dispersed throughout the data. There are some extremely low values as well as some extremely high values with one modal class and several classes fairly evenly increasing and decreasing on either side of it.
The Weight histogram is also fairly evenly distributed. It has a slight dip in the middle of the data, but overall it increases in the middle of the data and decreases towards the end of the data. The central tendency is from 1780 to 3700, where over 78% of the data lies. The dispersion in the weight histogram is also pretty even with some extremely low values and some extremely high values. The modal class is from 2740 to 3220 and the classes on either side of it are evenly decreasing. 2. d. Descriptive MPG Statistics Table