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First fill in this table with the appropriate values, all decimals to 2 decimal places:
\n\n | $\\overline{x}_i$ | \n$s_i$ | \n$T_i$ | \n$\\sum x^2$ | \n$n_i$ | \n
Group A | \n[[0]] | \n[[1]] | \n[[2]] | \n[[3]] | \n6 | \n
---|---|---|---|---|---|
Group B | \n[[4]] | \n[[5]] | \n[[6]] | \n[[7]] | \n6 | \n
Group C | \n[[8]] | \n[[9]] | \n[[10]] | \n[[11]] | \n6 | \n
\n | \n | \n | $G=\\;$[[12]] | \nSum of Squares=[[13]] | \n$N=18$ | \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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false, "scripts": {}, "precision": "2", "precisionType": "dp", "extendBaseMarkingAlgorithm": true, "variableReplacementStrategy": "originalfirst", "customMarkingAlgorithm": "", "minValue": "ssq[2]", "mustBeReduced": false, "marks": 0.5, "allowFractions": false, "precisionPartialCredit": 0, "correctAnswerStyle": "plain", "precisionMessage": "You have not given your answer to the correct precision.", "maxValue": "ssq[2]"}, {"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": "g", "mustBeReduced": false, "marks": 0.5, "allowFractions": false, "precisionPartialCredit": 0, "correctAnswerStyle": "plain", "precisionMessage": "You have not given your answer to the correct precision.", "maxValue": "g"}, {"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": "ss", "mustBeReduced": false, "marks": 0.5, "allowFractions": false, "precisionPartialCredit": 0, "correctAnswerStyle": "plain", "precisionMessage": "You have not given your answer to the correct precision.", "maxValue": "ss"}]}, {"showFeedbackIcon": true, "extendBaseMarkingAlgorithm": true, "variableReplacementStrategy": "originalfirst", "variableReplacements": [], "type": "gapfill", "customMarkingAlgorithm": "", "prompt": "\nNow find the following, all to 2 decimal places:
\n$\\displaystyle TSS\\;=\\;$[[0]], $\\displaystyle BTSS\\;=\\;$[[1]], $\\displaystyle RSS\\;=\\;$[[2]]
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\nSource | df | SS | MS | VR |
---|---|---|---|---|
Between Treatments | \n[[0]] | \n[[1]] | \n[[2]] | \n[[3]] | \n
Residual | \n[[4]] | \n[[5]] | \n[[6]] | \n- | \n
Total | \n[[7]] | \n[[8]] | \n- | \n- | \n
Also calculate the estimated standard error of the mean : [[9]]
\nNote that VR is found by taking the ratio of two of the values in this table.
\nInput all numbers to 2 decimal places.
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"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": "n-1", "mustBeReduced": false, "marks": 0.5, "allowFractions": false, "precisionPartialCredit": 0, "correctAnswerStyle": "plain", "precisionMessage": "You have not given your answer to the correct precision.", "maxValue": "n-1"}, {"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": "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": "\nGive 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$10\\%$ | \n$5\\%$ | \n$1\\%$ | \n$0.1\\%$ | \n
$2.70$ | \n$3.68$ | \n$6.36$ | \n$11.34$ | \n
$p$ 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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", "Strong Evidence
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", "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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", "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.
\nGroup A ($0$ units) | \n$\\var{r1[0]}$ | \n$\\var{r1[1]}$ | \n$\\var{r1[2]}$ | \n$\\var{r1[3]}$ | \n$\\var{r1[4]}$ | \n$\\var{r1[5]}$ | \n
---|---|---|---|---|---|---|
Group B ($2$ units) | \n$\\var{r2[0]}$ | \n$\\var{r2[1]}$ | \n$\\var{r2[2]}$ | \n$\\var{r2[3]}$ | \n$\\var{r2[4]}$ | \n$\\var{r2[5]}$ | \n
Group C ($4$ units) | \n$\\var{r3[0]}$ | \n$\\var{r3[1]}$ | \n$\\var{r3[2]}$ | \n$\\var{r3[3]}$ | \n$\\var{r3[4]}$ | \n$\\var{r3[5]}$ | \n
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