Mathematics, 16.11.2020 16:30, Michael845313

The group of 25 victims scored an average of 25.3 with a sample standard deviation of 9 on the depression scale. The group of 23 bully-victims scored an average of 20.5 with a sample standard deviation of 8 on the same scale. You do not have any presupposed assumptions about whether victims or bully-victims will be more depressed, so you formulate the null and alternative hypotheses as:

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answered: lashaeperson

Complete Question

The group of 25 victims scored an average of 25.3 with a sample standard deviation of 9 on the depression scale. The group of 23 bully-victims scored an average of 20.5 with a sample standard deviation of 8 on the same scale. You do not have any presupposed assumptions about whether victims or bully-victims will be more depressed, so you formulate the null and alternative hypotheses as:

$H_o: \ \ \mu_{victims} - \mu_{bully-victims} = 0H1: \ \ \mu _{victims} - \mu_{bully-victims} \ne 0$

You conduct an independent-measures t test. Given your null and alternative hypotheses,

this is a ________ [ Select ] ["two-tailed", "one-tailed"] test.

The degree of freedom is __________ [ Select ] ["46", "48", "24", "22"]

and for an alpha of .01, the critical t is +/- _________ [ Select ] ["2.704", "2.021", "1.684"]

In order to calculate the t statistic, you first need to calculate the standard error under the assumption that the null hypothesis is true. In order to calculate the standard error, you first need to calculate the pooled variance. The pooled variance is ________ [ Select ] ["72.8696", "145", "0.3756", "71.3201"] .

The standard error is ___________ [ Select ] ["2.4664", "2.5572", "1.9543", "72.8712"] .

The t-statistic is _________ [ Select ] ["1.95", "2.55", "-1.70", "-2.25"]

First Question

The correct option is "two-tailed"

Second Question

The correct option is "46"

Third Question

The correct option is "2.704"

Fourth Question

The correct option is "72.8696"

Five Question

The correct option is "2.4664"

Sixth Question

The correct option is "1.95"

Step-by-step explanation:

From the question we are told that

The number of victims is n_1 = 25

The sample mean is $\= x_1 = 25.3$

The standard deviation is s_1 = 9

The number of bully victims is n_2 = 23

The sample mean is $\= x_2 = 20.5$

The standard deviation is s_2 = 8

Generally this is a two -tailed test because from the null and the alternative hypothesis we see that the test is know whether the mean number of victims is significantly more depressed than bully -victims or significantly less depressed than bully -victims

Generally the degree of freedom is mathematically represented as

df = n_1 + n_2 -2

=> df = 25 + 23 -2

=> df = 46

Generally from t distribution table the critical value of $\alpha = 0.01$ for a two-tailed test at a degree of freedom of df = 46 is

$t_{0.01 , 46} = \pm 2.704$

Generally the pooled variance is mathematically represented as

$s^2 = \frac{(n_1 - 1) s_1^2 + (n_2 - 1)s_2^2}{df}$

=> $s^2 = \frac{(25 - 1) 9^2 + (23 - 1)8^2}{46}$

=> s^2 = 72.8696

Generally the standard error is mathematically represented as

$SE = s \sqrt{\frac{1}{n_1} + \frac{1}{n_2} }$

$SE = \sqrt{s^2} * \sqrt{\frac{1}{n_1} + \frac{1}{n_2} }$

=> $SE = \sqrt{72.8696} * \sqrt{\frac{1}{25} + \frac{1}{23} }$

=> SE = 2.4664

Generally the test statistics is mathematically represented as

$t = \frac{\= x_ 1 - \= x_2}{SE }$

=> $t = \frac{25.3 - 20.5}{ 2.4664 }$

=> t =1.95

answered: Guest

well my understanding of this question is they want you to use the y=14.1x -2.3 and put the coordinates they gave you onto the line segment of y=14.1x -2.3

step-by-step explanation:

answered: Guest

25 inches - 0.694 yards