An Analyst Is Assigned a Blind Quality Control Sample of Blood

question 27

Multiple Choice

An analyst is assigned a blind quality control sample of blood containing a drug metabolite. He tests ten separate portions and obtains the following data for the concentration in ug/mL:
25.2
24.8
26.6
27.0
24.0
26.0
25.5
26.3
24.9
23.9
Calculate the sample standard deviation and report to three significant figures. Use a spreadsheet or calculator.

• A) 0.995
• B) 1.06
• C) 9.95
• D) 1.00
• E) 23.0

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Definitions:

DfWG

Degree of Freedom Within Groups, which quantifies the variability of observations within individual groups in an ANOVA test.

One-way ANOVA

A statistical test utilized to compare the means of three or more independent groups to determine if there is a significant difference among them.

F-ratio

A statistic commonly used in ANOVA (Analysis of Variance) to compare the variances between groups to see if there is a significant difference between them.

Critical Value

A point on the scale of the test statistic beyond which the null hypothesis is rejected; it depends on the chosen significance level.