/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 27 The effect of loneliness among c... [FREE SOLUTION] | 91Ó°ÊÓ

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The effect of loneliness among college students was examined in the article "The Importance of Perceived Duration: Loneliness and Its Relationship to Self-Esteem and Academic Performance" (Journal College Student Development \([1994]: 456-460\) ). Based on reported frequency and duration of loneliness, subjects were divided into two groups. The first group was the short-duration loneliness group, and the second was the long-duration loneliness group. A self-esteem inventory was administered to students in both groups. For the short-duration group, the reported mean self-esteem score was \(76.78\) and the standard deviation was \(17.80\). For the long-duration group, the mean and standard deviation were \(64.00\) and \(15.68\), respectively. Do the data support the researcher's claim that mean self-esteem is lower for students classified as having long-duration loneliness? Test the relevant hypotheses using \(\alpha=.01\). Be sure to state any assumptions that are necessary for your test to be valid.

Short Answer

Expert verified
Without exact sample sizes, it is impossible to calculate the t-statistic or critical t-value and hence, cannot reach to a definitive conclusion whether to reject or not reject the null hypothesis. However, the step-by-step approach and methodology provided above is correct for conducting an independent T-test assuming equal variances.

Step by step solution

01

Identify a null and alternative hypothesis

The null hypothesis is that there's no difference in mean self-esteem scores between the short and long-duration loneliness groups. In mathematical notation, this is \(H_0: \mu_1 = \mu_2\). The alternative hypothesis is that the mean self-esteem score in the long-duration loneliness group is less than the short-duration group, or \(H_a: \mu_1 > \mu_2\).
02

Select the level of significance

The level of significance, also referred as alpha (\(\alpha\)), is the probability of rejecting the null hypothesis when it is in fact true. In this case, \(\alpha = 0.01\).
03

Calculate the test statistic using the Independent T-test formula

The formula for the independent samples t-test is \(t = \frac{\overline{x}_1 - \overline{x}_2}{\sqrt{{s_1^{2}/n_1 + s_2^{2}/n_2}}}\), where \(\overline{x}_1\) and \(\overline{x}_2\) are the sample means, \(s_1\) and \(s_2\) are the sample standard deviations, and \(n_1\) and \(n_2\) are sample sizes. Fill these values from the given data: \(\overline{x}_1 = 76.78, s_1 = 17.80\) for the short-duration group, and \(\overline{x}_2 = 64.00, s_2 = 15.68\) for the long-duration group. Please note that sample sizes \(n_1\) and \(n_2\) aren't specified in the problem, thus couldn't be incorporated in the formula.
04

Find the critical t-value

Find the critical t-value from a t-distribution table by looking up the degree of freedom (df) and the significance level. The degree of freedom is typically calculated as \(df = n_1 + n_2 - 2\). However, due to the lack of sample sizes in the problem, we couldn't calculate the exact critical t-value.
05

Decide to reject or fail to reject the null hypothesis

If the calculated t is less than the critical t-value found in the t-distribution table, then fail to reject the null hypothesis. If the calculated t is greater than the critical t-value, then reject the null hypothesis.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Independent T-test
The independent t-test is a statistical method used to determine if there are any significant differences between the means of two independent groups. This is particularly useful when you want to compare two groups' outcomes to see if they are significantly different, as was done in the study regarding loneliness and self-esteem among college students.

In the context of our exercise, the independent t-test helps to compare the average self-esteem scores between two groups of students. One group consists of those experiencing short-duration loneliness, and the other consists of students experiencing long-duration loneliness.
  • The independent t-test assumes that the variables are continuous and approximately normally distributed within each group.
  • The variances of the two groups are equal.
  • The data points are independent of each other, meaning the self-esteem score of one student doesn't affect that of another.
When these assumptions are met, the independent t-test can help researchers like those in the study determine whether the observed differences in self-esteem levels are statistically significant or could have occurred by chance.
Null and Alternative Hypotheses
Hypothesis testing often involves the formation of a null hypothesis and an alternative hypothesis. The null hypothesis, denoted as \(H_0\), is a statement of no effect or no difference. It is a baseline assumption that any kind of effect observed in a study is due to chance.

In our study, the null hypothesis asserts that there is no significant difference in mean self-esteem scores between students with short-duration loneliness and those with long-duration loneliness. Mathematically, it is expressed as \(H_0: \mu_1 = \mu_2\).

The alternative hypothesis, denoted as \(H_a\), is what you want to prove. Here, it suggests that the mean self-esteem score for the long-duration loneliness group is lower than that for the short-duration group, expressed as \(H_a: \mu_1 > \mu_2\).

Understanding these hypotheses is crucial because they form the basis of the t-test and allow researchers to understand their research question. The null hypothesis serves as a neutral standpoint, while the alternative hypothesis is what the research aims to support.
Level of Significance
The level of significance, represented by \(\alpha\), is the probability threshold at which you will reject the null hypothesis. It quantifies the risk of making a Type I error, which is rejecting the null hypothesis when it is actually true. A common level of significance used in studies is 0.05 or 5%, but for more stringent tests, a lower level such as 0.01 or 1% is selected.

In the given exercise, the significance level is 0.01. This means the researchers were willing to accept a 1% chance of mistakenly rejecting the null hypothesis, indicating a high confidence level in the result of their test.

Choosing a level of significance often depends on the field of study and the critical nature of the decisions informed by the test. In sensitive areas like medical research, lower alpha levels might be used to minimize the chance of error. In our exercise related to self-esteem, the significance level helps determine whether the observed statistics support the idea that long-duration loneliness substantially affects self-esteem in a negative way.
Self-Esteem and Loneliness in College Students
Loneliness and self-esteem are critical factors influencing college students' well-being and academic performance. In the context of this exercise, researchers explored how varying durations of loneliness affect self-esteem among college students.

The study divided students into two groups based on their reported periods of loneliness:
  • Short-duration loneliness group.
  • Long-duration loneliness group.
Each group was then assessed using a self-esteem inventory, which measures how individuals feel about themselves and their worthiness.
The findings propose that students with long-duration loneliness experience lower self-esteem levels compared to their peers with short-duration loneliness. Understanding the relationship between loneliness and self-esteem is crucial as it helps in developing interventions that can improve students' mental health and, consequently, their academic success.

This area of research underscores the importance of mental health resources and support systems in college environments, aiming to help students manage loneliness and maintain higher self-esteem levels.

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Most popular questions from this chapter

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