**Required Resources**

Read/review the following resources for this activity:

- OpenStax Textbook: Chapter 2, 3
- Lesson
- Minimum of 1 scholarly source

In your reference for this assignment, be sure to include both your text/class materials AND your outside reading(s).

**Initial Post Instructions**

Probability plays a major role in the medical community. Diagnoses are based on probabilities. They are really questions or “what if’s”, and are answered by the **probability** that the treatment will be the best for the ailment.

Let’s look at probability in terms of both the real world and the medical community.

- Survey 30 people to find out if they are left-handed or right-handed, and use the following chart to create a contingency table with the information.

Left handed Right handed Total Female Male Total

- Answer the following questions about the information in your contingency table:
- If a person is randomly selected from the survey participants, what is the probability that the person will be left-handed?
- If you randomly choose a female from the people you surveyed, what is the probability that she is left-handed?
- What is the odds ratio of choosing a left-handed
**female**? - What is the relative risk of choosing a left-handed
**female**?

Example

Green | Blue | Total | |

Cats | 40 (A) | 20 (B) | 60 (A+B) |

Dogs | 30 (C) | 40 (D) | 70 (C+D) |

Total | 70 (A+C) | 60 (B+D) | 130 (A+B+C+D) |

- Probability of Green – (A+C)/(A+B+C+D): 70/130 = 0.54
- Probability of Green Cat – A/(A+B): 40/60 = 0.67
- Odds Ratio of Green Cat – (A/B)/(C/D) or AD/BC: (40
*40)/(20*30) = 1600/600 = 2.67 - Relative Risk of Green Cat – [A/(A+C)]/[B/(B+D)]: (40/70)/(20/60) = 1.71

- Skim through at least one of the following articles on left-handed vs. right-handed people from the Chamberlain Library. Answer the following question: How do the probabilities and percentages for your study compare to those in the study you read?

## Solution:

**Week 4 Discussion: Probability**

Left-handed | Right-handed | Total | |

Female | 2 (a) | 16 (b) | 18 (a+b) |

Male | 3 (c) | 9 (d) | 12(c+d) |

Total | 5(a+c) | 25(b+d) | 30 (a+b+c+d) |

The table above shows data which I collected from 30 participants; all of whom were randomly picked among my colleagues. I simply selected the first 30 persons to have signed in on the morning I collected the data. Holmes, Illowsky, and Dean (2019) describe probability as “measure that is associated with how certain we are of outcomes of a particular experiment or activity”….C**lick link below to purchase full tutorial at $5**