Summary of Lecture 3.3 - Describing Numerical Data - Median and Mode
Median is the middle value in an ordered data set that divides it into the bottom 50% and top 50%.
To compute the median, arrange data in increasing order, and if the number of observations is odd, the median is the middle value. If the number of observations is even, the median is the average of the middle two values.
The median is not sensitive to outliers compared to the mean.
Mode is the value that appears most frequently in a data set.
Adding a constant to a data set does not change the median, but the new mode is the old mode plus the constant.
Multiplying the entire data set by a constant results in the new mode being the old mode multiplied by the constant.
Speakers/sources
- Not mentioned.
Notable Quotes
— 15:43 — « 7 occurs twice again you can see that the difference between the first data set and the second data set is only one observation namely 12 appears in the first data set 105 appears in the second data set the mode again is 7 for this data set., »
— 16:05 — « has all six values that are distinct hence there is no mode for the third data set., »
— 18:20 — « I add 5 marks just as earlier and you can see that the data set in ascending order becomes 40 43 I dont need it in ascending order now but nevertheless I can see that the mode now is 73 which corresponds to 68 plus 5 hence the new mode is nothing but the old mold plus the constant., »
— 19:14 — « i can remove the c so i have c into x 5 plus x 6 by 2 x 5 plus x 6 by 2 was my old median so my old median into the constant will give me the new median and this we can see in our example., »
— 19:49 — « the new mode is 27.2 this appears twice and we can verify that this 27.2 is 0.4 times 68., »
Category
Educational