Anova

#1
hello, please i need an urgent help to answer those three questions and the explication of each answer :
1) To determine whether the test statistic of ANOVA is statistically significant, it can be compared to a critical value. What two pieces of information are needed to determine the critical value?

a. sample size, number of groups
b. mean, sample standard deviation
c. expected frequency, obtained frequency
d. Mean square between groups, Mean square within the groups

2) When conducting a one-way ANOVA, the _______ the between-treatment variability is when compared to the within-treatment variability, the _______ the value of FDATA will be tend to be.

a. smaller, larger
b. smaller, smaller
c. larger, larger
d. smaller, more random
e. larger, more random

3)Suppose the critical region for a certain test of the null hypothesis is of the form F > 9.48773 and the computed value of F from the data is 1.86. Then:

a. H0 should be rejected.
b. The significance level is given by the area to the left of 9.48773 under the appropriate F distribution.
c. The significance level is given by the area to the right of 9.48773 under the appropriate F distribution. The hypothesis test is two-tailed
e. None of these

I Know that the responses are available on google but i need to be sure of the answers and especially i need an explication of it.

Thank you
 
Last edited:

ondansetron

TS Contributor
#2
Hi! We're happy to help.

First, tell us what you think the answer is for each question and why that is the correct answer. Then, we can go about helping you arrive at the correct answer and explanation.

#2 appears to be missing information in the question stem since it ends with ":" and isn't a complete idea.
#3 appears to have C & D on one line.
 
#3
according to many websites the answer of the 1st is : a) sample size, number of groups
the answer of the second is : b) smaller, smaller

teh answer of the third is : c) The significance level is given by the area to the right of 9.48773 under the appropriate F distribution. The hypothesis test is two-tailed

but i can not tell you why because what i am looking for here is what are the correct answers and especially " why" so im looking for the explanation to understand it thank you
 
#4
#2 appears to be missing information in the question stem since it ends with ":" and isn't a complete idea.
#3 appears to have C & D on one line.[/QUOTE]

to reply to what you said here for Q2 its just "." not ":" i will correct it
for Q3 no the quiz is just like that : c. The significance level is given by the area to the right of 9.48773 under the appropriate F distribution. The hypothesis test is two-tailed
im waiting thank you
 

ondansetron

TS Contributor
#5
What is "FDATA" mean in #2? Then maybe I can be more sure what they intended with the question.

For#3 I'm fairly certain there is a typo and "two tailed test" should be choice D. What can you find in your notes or textbook regarding the "tailedness" of an F-test? What is the definition of a significance level? What is the definition of a critical value?

You are correct for #1. Humor me for a moment, and use your text book or course notes to see what you can find about the F-distribution and F-statistics. Is there a SINGLE F-distribution or do many exist? This will help you answer why A (sample size and #groups) is correct. Also, what is "degrees of freedom" and does it apply here?
 
#8
I agree with ondansetron that reading a bit more about ANOVA in your textbook could help you a lot with answering the questions. However, if you prefer practice questions where the correct answer is explained, you may want to have a look here: http://statkat.com/selectquestions.php . You can find many practice questions about ANOVA here.