Making Inferences from a Sample custom essay

Hypothesis Testing:

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 terms of null and alternative hypotheses. 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, if the results are significant.

For example, a researcher asks whether attending a private secondary school leads to higher or lower performance on a test of social skills when compared to students attending publicly funded schools. After stating the hypotheses and collecting data, the researcher sees that the mean social skills scores for the two schools are different, but is the difference meaningful or just due to random variation? There must be a significant difference in order to say that the two schools really do have students with different social skills.

Scenario:

Imagine that the drug for severe depression from this week’s Discussion was approved for use in humans. Researchers now want to know whether people using this drug have a different life expectancy than the rest of the general population. A sample of 100 patients who use the drug are followed over time. Those that use the drug have a mean life expectancy of 71.30 years. The mean life expectancy for the general population is 75.62 years. The population standard deviation is 28.

Assignment:

To complete this Assignment, responses to the following:

  • Identify the independent and dependent variables.
  • Explain whether the researcher should use a one-tailed or a two-tailed ztest and why.
  • State the null hypothesis in words (not formulas).
  • State the alternative hypothesis in words (not formulas).
  • Calculate the obtained zscore by hand and state the critical value with an alpha of .05. Provide your calculations in your Assignment submission.
  • Would you retain or reject the null hypothesis? Why?
  • Explain whether the results are significant, and why or why not.
  • What should the researcher conclude about the life expectancy of the sample in comparison to the population?
  • In general, explain the relationship between zscores and the standard deviation.

 

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Using t Tests Custom essay

In order to set up a research study, you must state your expectations and hypothesize what will happen if you compare your participants to those in the general population or to those in another group. You also need to determine the type of relationship you expect. In comparing means of groups, you may predict that one group’s mean will be higher than another. You may predict that one group’s mean will be lower than another. In either of these cases, you will implement a one-tailed test because you are predicting the direction of the relationship. If you think the means will be different but you are not sure if they will be higher or lower, you implement a two-tailed test. Once you plan your study and state your hypotheses, you collect your data, calculate results, and interpret the meaning of those results.

In this Discussion, you will create a scenario that would require using the one-sample t test and then explain what you would change in order to turn the one-sample t test into a two-sample t test. While you will not need to complete calculations, you will be asked to explain your study design and discuss why you made the choices you did. This experience will help you later to review studies and critique the interpretation of data.

Post your one-sample t test scenario. What would need to change in the scenario to result in the need for a two-sample t test? Explain whether the two-sample scenario would be categorized as having independent samples or related samples and discuss why. Support your post using the Learning Resources

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Computing t Tests Custom essay

The one-sample t test discussed in Chapter 6 requires that you know the population mean. It is unusual to have this information, so most studies compare two samples instead. Each sample measures a different condition of the independent variable.

Before conducting a study, it is important to know if you would need to conduct a matched-samples t test or an independent-samples t test. Independent samples consist of two groups of different people. One group has been randomly selected and is not specifically tied to who is in the other group. Matched samples are groups that are deliberately selected to be similar to each other (matched pairs) or they are the same people in both groups (repeated measures). For example, you might want to select two groups that have similar heights. If height could affect the experiment, it could be best to match the groups on that variable. This Assignment will allow you to convey your understanding of the basic concepts related to t testing and will allow you to practice setting up and conducting an inferential parametric test in SPSS.

Scenario:

Imagine you are a researcher who believes that a relaxation technique involving visualization will help people with mild insomnia fall asleep faster. You randomly select a sample of 20 participants from a population of mild insomnia patients and randomly assign 10 to receive visualization therapy. The other 10 participants receive no treatment.

You then measure how long (in minutes) it takes participants to fall asleep. Your data are below. The numbers represent the number of minutes each participant took to fall asleep.

No Treatment (X1) Treatment (X2)
22 19
18 17
27 24
20 21
23 27
26 21
27 23
22 18
24 19
22 22

Assignment:

To complete this Assignment, submit by Day 7 a response to each of the following:

  • Explain whether you chose to use an independent-samplestest or a matched-samples t test. Provide a rationale for your choice.
  • Identify the independent and dependent variables.
  • Knowing you believe the treatment will reduce the amount of time to fall asleep, state the null and alternate hypotheses in words (not formulas).
  • Explain whether you would use a one-tailed or two-tailed test and why.
  • Explain whether you have homogeneity of variance, and explain how you know. Explain why it is important to know if you have homogeneity of variance.
  • Identify the obtained tvalue for this data set using SPSS.
  • Identify the degrees of freedom and explain how you determined it.
  • Identify the pvalue.
  • Explain whether you should retain or reject the null hypothesis and why.
  • Explain what you can conclude about the effectiveness of visualization therapy

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Classical Music; Early Abolitionist Art and Literature Custom essay

using sources under the Explore heading as the basis of your response:

Listen to one (1) composition (for a symphony) by Haydn or Mozart, either at the Websites below or in this week’s Music Folder. Identify the work that you have chosen, and describe the way in which the composition expresses the specific qualities of the Classical music style. Use the key terms from the textbook that are related to that particular music style, and explain what you like or admire about the work. Compare it to a specific modern musical work for which you might use the term “classic” or “classical”.

Explain whether you think an autobiographical or fictional account by a slave (such as Phillis Wheatley and Olaudah Equiano) is more persuasive than a biographical or fictional account by a white author (such as John Gabriel Stedman or Aphra Behn). Explain whether you believe the representations of slavery in the visual arts (such as William Blake’s illustrations, William Hackwood’s cameo, or John Singleton Copley’s painting) were more compelling and convincing of the injustices of slavery than the literary representations already mentioned. In your explanations, use specific examples and consider both audience and the content and nature of the work. Identify the literary or art form in modern times that you think is most effective at depicting injustice.

Explore:

Classical Music

Chapter 25 (pp. 826-832), classical style described; examples; review the Week 3 “Music Folder”
Haydn at http://www.youtube.com/watch?v=JESXMWrwzVQ and http://www.npr.org/artists/16110605/franz-joseph-haydn
Mozart at http://www.youtube.com/watch?v=hywOY9BS9tQ and http://www.npr.org/artists/15327819/wolfgang-amadeus-mozart

Early Abolitionist Art & Literature

Chapter 26 (pp. 870-2): Equiano, Stedman, Wheatley, Behn; Chapter 26 (pp. 877-879): Equiano and Behn
Wheatley at http://www.vcu.edu/engweb/webtexts/Wheatley/phil.htm
Chapter 26 (pp. 870-873): Blake, Hackwood, Copley

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Timeline of Gendered Movements Custom essay

Overview

If there is one important lesson you can learn as social scientists it is this: historical events never appear in isolation, but instead, are connected to previous events. In this Assignment you will develop a 6-point timeline that shows how the counterculture movements and issues of equality were intertwined to define the 1960s. Give the timeline a descriptive title. Use footnotes or endnotes to fully describe the reason for including each item

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The differing approaches of nursing leaders and managers to issues in practice Custom essay

Write a 1,000-1,250-word essay describing the differing approaches of nursing leaders and managers to issues in practice. To complete this assignment, do the following:

  1. Select an issue from the following list: nursing shortage and nurse turn-over, nurse staffing ratios, unit closures and restructuring, use of contract employees (i.e., registry and travel nurses), continuous quality improvement and patient satisfaction, and magnet designation.
  2. Compare and contrast how you would expect nursing leaders and managers to approach your selected issue. Support your rationale by using the theories, principles, skills, and roles of the leader versus manager described in your readings.
  3. Identify the approach that best fits your personal and professional philosophy of nursing and explain why the approach is suited to your personal leadership style.
  4. Use at least two references

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