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First fill in this table with the appropriate values, all decimals to 2 decimal places:

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n
 $\\overline{x}_i$$s_i$$T_i$$\\sum x^2$$n_i$
Group A[[0]][[1]][[2]][[3]]6
Group B[[4]][[5]][[6]][[7]]6
Group C[[8]][[9]][[10]][[11]]6
   $G=\\;$[[12]]Sum of Squares=[[13]]$N=18$
\n

Note that in doing this you will have supplied the sample means and sample standard deviations for the three groups.

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Now find the following, all to 2 decimal places:

\n

$\\displaystyle TSS\\;=\\;$[[0]], $\\displaystyle BTSS\\;=\\;$[[1]], $\\displaystyle RSS\\;=\\;$[[2]]

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Now complete the ANOVA table using the values to 2 decimal places obtained above:

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
SourcedfSSMSVR
Between Treatments[[0]][[1]][[2]][[3]]
Residual[[4]][[5]][[6]]-
Total[[7]][[8]]--
\n

Also calculate the estimated standard error of the mean : [[9]]

\n

Note that VR is found by taking the ratio of two of the values in this table.

\n

Input all numbers to 2 decimal places.

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"customMarkingAlgorithm": "", "minValue": "rss", "mustBeReduced": false, "marks": 0.5, "allowFractions": false, "precisionPartialCredit": 0, "correctAnswerStyle": "plain", "precisionMessage": "You have not given your answer to the correct precision.", "maxValue": "rss"}, {"showFeedbackIcon": true, "notationStyles": ["plain", "en", "si-en"], "variableReplacements": [], "type": "numberentry", "showCorrectAnswer": true, "showPrecisionHint": false, "mustBeReducedPC": 0, "strictPrecision": false, "unitTests": [], "correctAnswerFraction": false, "scripts": {}, "precision": "2", "precisionType": "dp", "extendBaseMarkingAlgorithm": true, "variableReplacementStrategy": "originalfirst", "customMarkingAlgorithm": "", "minValue": "mrs", "mustBeReduced": false, "marks": 0.5, "allowFractions": false, "precisionPartialCredit": 0, "correctAnswerStyle": "plain", "precisionMessage": "You have not given your answer to the correct precision.", "maxValue": "mrs"}, {"showFeedbackIcon": true, 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"extendBaseMarkingAlgorithm": true, "variableReplacementStrategy": "originalfirst", "customMarkingAlgorithm": "", "minValue": "tss", "mustBeReduced": false, "marks": 0.5, "allowFractions": false, "precisionPartialCredit": 0, "correctAnswerStyle": "plain", "precisionMessage": "You have not given your answer to the correct precision.", "maxValue": "tss"}, {"showFeedbackIcon": true, "notationStyles": ["plain", "en", "si-en"], "variableReplacements": [], "type": "numberentry", "showCorrectAnswer": true, "showPrecisionHint": false, "mustBeReducedPC": 0, "strictPrecision": false, "unitTests": [], "correctAnswerFraction": false, "scripts": {}, "precision": "2", "precisionType": "dp", "extendBaseMarkingAlgorithm": true, "variableReplacementStrategy": "originalfirst", "customMarkingAlgorithm": "", "minValue": "stderror-tol", "mustBeReduced": false, "marks": 1, "allowFractions": false, "precisionPartialCredit": 0, "correctAnswerStyle": "plain", "precisionMessage": "You have not given your answer to the correct precision.", "maxValue": "stderror+tol"}]}, {"shuffleChoices": false, "showFeedbackIcon": true, "extendBaseMarkingAlgorithm": true, "variableReplacementStrategy": "originalfirst", "variableReplacements": [], "type": "1_n_2", "minMarks": 0, "customMarkingAlgorithm": "", "prompt": "\n

Give the value of $VR$ you have found, choose the range for the $p$ value by looking up the critical values of $F_{2,15}$ (one-sided).

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n
$10\\%$$5\\%$$1\\%$$0.1\\%$
$2.70$$3.68$$6.36$$11.34$
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$p$ less than $0.1\\%$

", "

$p$ lies between $0.1\\%$ and $1\\%$

", "

$p$ lies between $1 \\%$ and $5\\%$

", "

$p$ lies between $5 \\%$ and $10\\%$

", "

$p$ is greater than $10\\%$

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Given the $p$-value and the range you have found, what is the strength of evidence against the null hypothesis that the mean times taken are the same for the three groups?

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Very Strong Evidence

", "

Strong Evidence

", "

Evidence

", "

Weak Evidence

", "

No Evidence

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Hence what is your decision based on the above ANOVA analysis?

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We reject the null hypothesis at the $0.1\\%$ level

", "

We reject the null hypothesis at the $1\\%$ level.

", "

We reject the null hypothesis at the $5\\%$ level.

", "

We do not reject the null hypothesis but consider further investigation.

", "

We do not reject the null hypothesis.

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One-way ANOVA example

", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "

The following data arose in a comparison of the effects of alcohol on the time taken to complete a task. There were three groups of subjects; Group A had no alcohol, Group B had $2$ units over one hour and Group C had $4$ units over one hour. The responses are the times (in seconds) taken to complete a word-matching task.

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Group A ($0$ units)$\\var{r1[0]}$$\\var{r1[1]}$$\\var{r1[2]}$$\\var{r1[3]}$$\\var{r1[4]}$$\\var{r1[5]}$
Group B ($2$ units)$\\var{r2[0]}$$\\var{r2[1]}$$\\var{r2[2]}$$\\var{r2[3]}$$\\var{r2[4]}$$\\var{r2[5]}$
Group C ($4$ units)$\\var{r3[0]}$$\\var{r3[1]}$$\\var{r3[2]}$$\\var{r3[3]}$$\\var{r3[4]}$$\\var{r3[5]}$
\n\n

 

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