Question

Defatted blackcurrant seeds (DBS) could be used as a dietary supplement in gluten-free bread but their use may affect texture. A 2011 study measured bread volume (in cm) using independent random samples of bread loaves baked with flours containing different DBS levels. The data showed no skew or outliers. Here are the summary statistics: Flour type z Mean StDev No DBS 00 552 18 5% DBS 00 525 23 15% DBS 00 485 24 We want to know if bread volume is significantly affected by the type of flour used.

Which inference procedure should be used?
1. chi-square for two-way tables
2. one sample or matched-pairs t procedure for a mean
3. z procedure for a proportion
4. two sample t procedure for two means
5. ANOVA for several means

Answer 1

Note: This is the correct table format.

Flour type z Mean StDev

No DBS 00 552 18

5% DBS 00 525 23

15% DBS 00 485 24

Answer:

5. ANOVA for several means

Explanation:

In this question, three different means of the data are compared. ANOVA is used for comparing between two or more means to test for differences. It extends the z and t test that are only used for comparing two means.

Since three means are compared, the inference procedure to be used is ANOVA.