Journal 4 PDF

Preview

Summary

learning Journal 4...

Description

2. a) What does the symbol x-bar represent? The symbol x-bar represents the sample mean which is the mean or average of sample of total population. All sample values are added and divided by the number of values of the same sample. (Yakir, 2011) b) What does the Greek letter mu (μ) represent as it was used in this week's lessons? The Greek letter mu (μ) is, as I understand, representing entire population where the mean represents a sample. (Yakir, 2011). For example a score of a college test in mathematics. Instead of choosing a sample of students, all the students who took the test will be the population.

c) What is the difference between x-bar and mu? One of the differences is that the values in the x-bar are not capitalized like in the mu formula. Both are calculated exactly the same way. 3. Mean a) Many people already know how to find the mean (average) of a sample of data by "adding all the numbers and dividing by the number of values in the dataset." Read Chapter 4, and then describe, in your own words, another method of finding the mean by using the sample space (list of possible values) and probabilities (the technique is in the book). Create a list of seven, 2digit numbers (with no duplicates) and another set of seven probabilities (with no duplicates). The probabilities must add to 1. Value Probabilit y

12 0.15

17 0.13

11 0.07

19 0.10

15 0.30

22 0.05

14 0.20

Now I will create formulas which I am going to enter in to R. As reference I will use the example in Yakir textbook on page 57. value probability mean(value) [1] 15.71429 > mean(probability) [1] 0.1428571 b) Describe in your own words what your calculation is doing and what the answer means.

The mean is the sum of the data which is divided by the number of the data. Ex.: sum of the values is 110; divided with 7; gives 15.71429; The same calculation with the probability numbers gives 0.1428571

Reference:  Yakir, B. (2011, March). Introduction to Statistical Thinking (With R, Without Calculus). The Hebrew University. Retrieved from https://my.uopeople.edu/pluginfile.php/358031/mod_resource/content/3/IntroStat.pdf...