# Probability in Real Life

## Discussion: Probability in Real Life

Individuals of all ages use probability to make decisions in everyday activities. For instance, when deciding whether to cross a street with traffic, people estimate the odds of making it safely across. Consider the prevalence of probability in your daily life. How does knowing the likelihood of something occurring affect how you make daily decisions? Usually, you choose an option because you believe that it will have a more pleasing outcome than the other choice(s). If you knew your likelihood of succeeding or failing, you would have an even easier time making a decision. Each decision you make is influenced by probability. Using what you know about probability might help you make decisions of low importance, such as purchasing goods, but it can also play a role in making critically important decisions. For example, scientists often use probability testing to evaluate the safety of drugs for human use and to help determine the likely outcome of other high-stakes decisions.

For this week’s Discussion, you will have the opportunity to practice your understanding by describing probability “in real life.” You will select one age group (elementary school students, high school students, or colleague/significant other) and explain how you would teach probability to that group.

To prepare: Think about examples of how individuals of various ages use probability to make decisions, and decide which age group you will write about in your discussion response.

##### By Day 3

**Post**the following:

- An explanation of how you would initially teach the concept of probability to
**one**of the age groups, listed below, in a way they would understand. In other words, describe how you would initially present and explain the concept in order to create background knowledge and a basic understanding of probability. Be sure to Include the age group you chose in the**Subject**of your post.- Elementary school students
- High school students
- Colleague/significant other

- An example of a demonstration you could use to illustrate the concept of probability to the age group you chose.
- An example of how this age group might use probability to make decisions in everyday life.

Think outside the box by avoiding common examples such as coin tosses, decks of cards, and dice. Take care not to confuse the concepts of probability and relative frequency when writing your post.

Be sure to fully explain your rationale for each of your suggestions, and support your ideas with evidence from the text and Learning Resources.

Provide an APA reference list.

Assignment

## Assignment: z-Test

Hypothesis testing is the foundation of conducting research in psychology. Researchers must first determine the question they wish to answer and then state their prediction in a null hypothesis and an alternative hypothesis. Once the hypotheses are stated, researchers move on to data collection. However, once the results come in, the real challenge is to determine if they have meaning; that is, are the results statistically significant or just due to random variation?

This application will allow you to practice hypothesis testing by using z-scores to compare a single score to a population mean in order to determine if results are statistically significant. Download the data set that you will use for this Assignment from the Weekly Data Set forum found in Week 3. Be sure to watch this week’s instructional video in the introduction or Learning Resources folder before beginning your Assignment.

**Scenario**: Lucy wants to know how her fourth-grade daughter, Monica, scored on a test of reading comprehension compared to the population of other fourth graders in the school district. Luckily, Lucy has taken this course and knows that a z-score will help her understand Monica’s reading score in relation to the population. You can find the data for this Assignment in the Weekly Data Set forum found on the course navigation menu. (not posted yet) …will send once received,

##### By Day 7

- State the dependent variable.
- Explain whether Lucy should use a one-tailed or a two-tailed z-test and explain why.
- State the null hypothesis in words (not formulas).
- State the alternative hypothesis in words (not formulas).
- Calculate the obtained z-score by hand. Describe your calculations (i.e., show your work).
- When alpha is set at .05, the critical value is ± 1.96. Should the null hypothesis be retained or rejected? Explain why.
- Are the results statistically significant? How do you know?
- What should Lucy conclude about Monica’s reading comprehension score in comparison to the population?
- Lucy is excited that she remembers how to compute a z-score and does some additional computations to find Monica’s z-score in math. You can find the information you need in the Weekly Data Set forum. Use it to calculate Monica’s raw math score by hand. Provide your calculations in your Assignment submission (i.e., explain your work).

**Submit**responses to the following:

Be sure to fully explain the rationale for your answer to each question, including evidence from the text and Learning Resources.

Provide an APA reference list.

References

##### Required Readings

Heiman, G. (2015).Behavioral sciences STAT(2nd ed.). Stamford, CT: Cengage.

- Chapter 5, “Describing Data with z-Scores and the Normal Curve” (pp. 68–84)
- Chapter 6, “Using Probability to Make Decisions about Data” (pp. 88–102)
- Chapter 7, “Overview of Statistical Hypothesis Testing: The z-Test” (pp. 106–123)

Weekly Data Set: Your instructor will post the data set that you will need for the week’s Assignment to the Weekly Data Set forum found in the course navigation area of the classroom.

##### Required Media

Laureate Education (Producer). (2015d).Introduction to z-score[Video file]. Baltimore, MD: Author.Note:The video is available in this week’s Introduction section

Laureate Education (Producer). (2015k).Probability and introduction to inferential statistics[Video file]. Baltimore, MD: Author.Note:The video is available in this week’s Introduction section

##### Optional Resources

Rugg, G. (2008).Using statistics: A gentle introduction[E-book]. Retrieved from http://site.ebrary.com/lib/waldenu/docDetail.action?docID=10229869&p00=statistics

StatSoft. (2015).Electronic statistics textbook. Retrieved from http://www.statsoft.com/textbook/elementary-statistics-concepts/