1. When we state that there is homogeneity of variance, precisely which variances are homogeneous? Use...

1. When we state that there is homogeneity of variance, precisely which variances are homogeneous? Use words, not symbols.

2. It is important to keep the probability of making Type I equal to α. With a t-test, how do we keep the probability of Type I error in check?

Solutions

Expert Solution

The assumption of homogeneity of variance is that the variance within each of the populations is equal.Homogeneity of variance is an assumption underlying both t tests and F tests. Homogeneity of variance means the population variances of two or more samples are considered equal.

Or we can also says that the assumption of homogeneity of variance means that the level of variance for a particular variable is constant across the sample. If we have collected groups of data then this means that the variance of our outcome variable should be the same in each of these groups.

2. Since we know that in statistical inference , a type I error is the rejection of a true null hypothesis (also known as a "false positive" ). In t test we find the critical value of t test corresponding to given type 1error α which ist_α (say). So the probability of rejecting the null hypothesis when it is true is the probability that t > t_α. For example,

In a statistical test (such as a t test) with α= 0.05, if the null hypothesis is true then the probability of not obtaining a significant result is 1 – 0.05 = 0.95.

orchestra answered 1 year ago

Next > < Previous

Related Solutions

10) If we have homogeneity of variances and equal group sizes, why might we decide to...

10) If we have homogeneity of variances and equal group sizes, why might we decide to use a R-E-G-W-Q post hoc instead of a Bonferroni post hoc? (Note: Think Type I/Type II error)

When using the test for homogeneity of variance, basically four outcomes or options can be considered...

When using the test for homogeneity of variance, basically four outcomes or options can be considered if a violation of the homogeneity of variance assumption is violated. These include: Option 1: Since a violation of the homogeneity of variance assumption occurred, the independent t-test may not be the appropriate statistical procedure for analysis of data. Therefore, we may opt for a lower order non-parametric statistical test. Option 2: Since a violation of the homogeneity of variance assumption occurred, the independent...

The reason we use the word favorable and unfavorable when evaluating variances is made clear when...

The reason we use the word favorable and unfavorable when evaluating variances is made clear when we look at the closing of accounts. To see this, consider that (1) all variance accounts are closed at the end of each period (temporary accounts), (2) a favorable variance is always a credit balance, and (3) an unfavorable variance is always a debit balance. Write a half page memo to our instructor with three parts that answer the fallowing three requirements. (Assume that...

Find the expectation of pooled estimate of variance when the variances are the same

Explain when you use the χ 2-Test for Independence/Homogeneity and when you use the χ 2-Test...

Explain when you use the χ 2-Test for Independence/Homogeneity and when you use the χ 2-Test for Goodness-of-Fit. Why do you not compute a confidence interval for these two tests. (You should give at least two reasons.)

Regarding the scenario below, state below PRECISELY what criteria you are going to use to identify...

Regarding the scenario below, state below PRECISELY what criteria you are going to use to identify the top candidates based on the records provided. Be brief but be complete. -------------------------------------------------------------------------------------- Imagine you are hired for Moople, a well-known tech company that receives thousands of job applications from students every year. You are asked to create a program that algorithmically selects the applications that are worth a second look. Moople claims that algorithms will reduce costs and help negate the biases...

We have learned about Standard costs and associated variances in this chapter. Can a favorable variance...

We have learned about Standard costs and associated variances in this chapter. Can a favorable variance be a bad thing? Describe a realistic scenario where a favorable variance could be detrimental(have unwanted consequences elsewhere in the business).

In calculating budget variances the total variance was broken down into various components, when added up...

In calculating budget variances the total variance was broken down into various components, when added up they totaled the total variance. Explain why this is helpful in determing problems and in identifying the corrective action that should be taken to resolve the problems

Which are the similarities of Classical and Bayesian approaches of Inference? And when we use this...

Which are the similarities of Classical and Bayesian approaches of Inference? And when we use this for a data in what will be differ and why?

We have learned hypothesis tests for the mean (when population variance is known and when it...

We have learned hypothesis tests for the mean (when population variance is known and when it is unknown) for a percentage to see if the means of two sets of data are the same goodness of fit test test for independence For each type give a brief example. You do not have to solve the problem you give. Try to come up with a problem on your own

Subjects