AS Stats Chapter 2: Measures of Location and Spread

12 flashcards · Mathematics · by TheoTyson

1. What is the mode?

   The value or class which occurs most often.

2. What is the median?

   The middle value when the data is sorted in order.

3. What is the mean?

   The average of all of the values in the set.

4. How do you find the lower quartile?

   Divide the number of units by 4, and if it is not a whole number, round up and pick that data point, else, it is halfway between the next point.

5. How do you find the upper quartile?

   Find 3 /4 of the number of units, and if it is not a whole number, round up and pick that data point, else, it is halfway between the next point.

6. What is interpolation?

   Estimating data in between given values by assuming the the data is evenly distributed.

7. What is the range?

   The difference between the largest and smallest values in the data set.

8. What is the interquartile range?

   The difference between the upper quartile and the lower quartile.

9. What is the interpercentile range?

   The difference between the values of two given percentiles.

10. What is the relationship between variance and standard deviation?

    The standard deviation is the square root of the variance.

11. If data is coded using y=x−aby = \frac{x-a}{b}y=bx−a​ , then what is yˉ\bar{y}yˉ​ ?

    yˉ=xˉ−ab\bar{y} = \frac{\bar{x}-a}{b}yˉ​=bxˉ−a​

12. If data is coded using y=x−aby = \frac{x-a}{b}y=bx−a​ , then what is σy\sigma _yσy​ ?

    σy=σxb\sigma_y = \frac{\sigma_x}{b}σy​=bσx​​