Question

Q1

Cindy Ho, VP of Finance at Discrete Components, Inc. (DCI), theorizes that the discount level offered to credit customers affects the average collection period on credit sales. Accordingly, she has designed an experiment to test her theory using four sales discount rates (0%, 2%, 4%, and 6%) by randomly assigning five customers to each sales discount rate. An analysis of Cindy's data produced the following ANOVA table.

Source of Variation	SS	df	MS	F
Treatment	1844.2	3	614.7333	7.568277
Error	1299.6	16	81.225
Total	3143.8	19

Using ? = 0.01, the appropriate decision is _________.

		reject the null hypothesis ?1 = ?2 = ?3 = ?4
		reject the null hypothesis ?1 ? ?2 ? ?3 ? ?4
		do not reject the null hypothesis ?1 = ?2 = ?3 = ?4 = ?5
		do not reject the null hypothesis ?1 ? ?2 ? ?3 ? ?4 ? ?5
		do nothing Q2 Medical Wonders is a specialized interior design company focused on healing artwork. The CEO, Kathleen Kelledy, claims that artwork has healing effects for patients staying in a hospital, as measured by reduced length of stay. Her current client is a children’s cancer hospital. Kathleen is interested in determining the effect of three different pieces of healing artwork on children. She chooses three paintings (a horse photo, a bright abstract, and a muted beach scene) and randomly assigns six hospital rooms to each painting. In Kathleen's experimental design, "length of stay" is _______. the dependent variable a concomitant variable a treatment variable a blocking variable a constant Q3 BigShots, Inc. is a specialty e-tailer that operates 87 catalog websites on the Internet. Kevin Conn, Sales Director, feels that the style (color scheme, graphics, fonts, etc.) of a website may affect its sales. He chooses three levels of design style (neon, old world and sophisticated) and randomly assigns six catalog websites to each design style. Analysis of Kevin's data yielded the following ANOVA table. Source of Variation SS df MS F Between Groups 68102.33 2 34051.17 Within Groups 29177.67 15 1945.178 Total 97280 17 Using ? = 0.05, the observed F value is _____________. 0.5022 0.1333 1.9911 17.5100 22.4567

Answer 1

Q1:

By using df1=3 and df2=16, from F table, the critical value of F at ? = 0.01 is F*=5.29.

Since test statistic, F=7.568277 is greater than critical value, reject the null hypothesis.

The correct option is:

${\color{Red} \textup{reject the null hypothesis } \mu_1 = \mu_2 = \mu_3 = \mu_4}$

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Q2:

Since Kathleen is measuring "length of stay", its dependent variable.

The correct option is:

${\color{Red} \textup{the dependent variable} }$

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Q3

$F=\frac{MSbetween}{MSwithin}=\frac{34051.17}{1945.178}=17.51$

The correct option is:

${\color{Red} 17.5100}$