Avobenzone is one of the active ingredients in several commercially available sunscreens. It can be absorbed into the bloodstream when sunscreen is applied to the skin. The Food and Drug Administration has expressed concern about the safety of absorbing too much avobenzone. Researchers recruited 24 healthy volunteers to investigate avobenzone absorption for four different commercially available sunscreens: two sprays, a lotion, and a cream. Do the types of sunscreens (spray, lotion, and cream) differ in terms of how much avobenzone is absorbed into the blood? Subjects were randomly assigned to one of the four sunscreens, with six subjects for each. Subjects had 2 milligrams of sunscreen per 1 cm? applied to 75% of their body surface area (area outside of normal swimwear) four times per day for four days. The amount of avobenzone absorbed into the bloodstream (in nanograms per milliliter ap-plied, ng/mL) after 150 hours was then measured for each subject. For the purpose of analyzing the data us ing ANOVA, the logarithms of the measurements were used. Thus, for example, a value of 0 corresponds to an absorption of 1 ng/ mL and negative values correspond to absorptions less than 1 ng/ mL. Larger values of the logarithms correspond to larger levels of absorption. Figure 27.13 shows JMP ANOVA output for these data. Show the work on how the values are acquired. a. Do these data satisfy the conditions for ANOVA? b. State Ho and H. for the ANOVA F test and explain in words what ANOVA tests in this setting. c. Report your overall conclusions about whether the types of sunscreen differ in the mean amount of avobenzone absorbed into the bloodstream after 150 hours.

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Avobenzone is one of the active ingredients in several commercially available sunscreens. It can be absorbed into the bloodstream when sunscreen is applied to the skin. The Food and Drug Administration has expressed concern about the safety of absorbing too much avobenzone. Researchers recruited 24 healthy volunteers to investigate avobenzone absorption for four different commercially available sunscreens: two sprays, a lotion, and a cream. Do the types of sunscreens (spray, lotion, and cream) differ in terms of how much avobenzone is absorbed into the blood? Subjects were randomly assigned to one of the four sunscreens, with six subjects for each. Subjects had 2 milligrams of sunscreen per 1 cm? applied to 75% of their body surface area (area outside of normal swimwear) four times per day for four days. The amount of avobenzone absorbed into the bloodstream (in nanograms per milliliter ap-plied, ng/mL) after 150 hours was then measured for each subject. For the purpose of analyzing the data us ing ANOVA, the logarithms of the measurements were used. Thus, for example, a value of 0 corresponds to an absorption of 1 ng/ mL and negative values correspond to absorptions less than 1 ng/ mL. Larger values of the logarithms correspond to larger levels of absorption.

Figure 27.13 shows JMP ANOVA output for these data. Show the work on how the values are acquired.

a. Do these data satisfy the conditions for ANOVA?

b. State Ho and H. for the ANOVA F test and explain in words what ANOVA tests in this setting.

c. Report your overall conclusions about whether the types of sunscreen differ in the mean amount of avobenzone absorbed into the bloodstream after 150 hours.

The table displays comparative data for different topical treatments over several entries. Each treatment option—Spray 1, Spray 2, Lotion, and Cream—is associated with a set of numerical values that likely represent measurements or evaluations under various conditions.

### Table: Comparative Analysis of Topical Treatments

| Treatment | Entry 1 | Entry 2 | Entry 3 | Entry 4 | Entry 5 | Entry 6 |
|-----------|---------|---------|---------|---------|---------|---------|
| Spray 1   | 0.693   | 0.405   | 0.405   | -0.511  | -0.916  |
| Spray 2   | 0.588   | 0.000   | 0.000   | -0.511  | -0.693  | -1.204  |
| Lotion    | 1.386   | 0.693   | 0.182   | 0.095   | -0.511  | 0.511   |
| Cream     | -0.357  | -0.357  | -0.357  | -1.204  | -1.609  | -1.609  |

### Explanation of Data:
- **Spray 1:** Positive initial values, decreasing in later entries.
- **Spray 2:** Starts with positive and zero values, gradually decreases into negative territory.
- **Lotion:** Begins with a high positive value, fluctuates with both positive and negative entries.
- **Cream:** Consistently negative, with increasingly negative values in later entries.

This table could be used for educational purposes to illustrate statistical evaluation or comparative studies in dermatological research or product analysis.
Transcribed Image Text:The table displays comparative data for different topical treatments over several entries. Each treatment option—Spray 1, Spray 2, Lotion, and Cream—is associated with a set of numerical values that likely represent measurements or evaluations under various conditions. ### Table: Comparative Analysis of Topical Treatments | Treatment | Entry 1 | Entry 2 | Entry 3 | Entry 4 | Entry 5 | Entry 6 | |-----------|---------|---------|---------|---------|---------|---------| | Spray 1 | 0.693 | 0.405 | 0.405 | -0.511 | -0.916 | | Spray 2 | 0.588 | 0.000 | 0.000 | -0.511 | -0.693 | -1.204 | | Lotion | 1.386 | 0.693 | 0.182 | 0.095 | -0.511 | 0.511 | | Cream | -0.357 | -0.357 | -0.357 | -1.204 | -1.609 | -1.609 | ### Explanation of Data: - **Spray 1:** Positive initial values, decreasing in later entries. - **Spray 2:** Starts with positive and zero values, gradually decreases into negative territory. - **Lotion:** Begins with a high positive value, fluctuates with both positive and negative entries. - **Cream:** Consistently negative, with increasingly negative values in later entries. This table could be used for educational purposes to illustrate statistical evaluation or comparative studies in dermatological research or product analysis.
**Oneway Anova Analysis**

The image displays the results of a one-way ANOVA test, which is used to compare the means of different groups to determine if there are any statistically significant differences among them.

**Analysis of Variance Table:**

- **Source:**
  - **Group:**
    - Degrees of Freedom (DF): 3
    - Sum of Squares: 4.658577
    - Mean Square: 1.55286
    - F Ratio: 3.5813
    - Prob > F: 0.0320*
  - **Error:**
    - DF: 20
    - Sum of Squares: 8.672101
    - Mean Square: 0.43361
  - **C. Total:**
    - DF: 23
    - Sum of Squares: 13.330678

The probability value (Prob > F) is 0.0320, indicating that there is a statistically significant difference among the group means at the 5% significance level.

**Means and Standard Deviations:**

- **Level:**
  - **Cream:**
    - Number: 6
    - Mean: -0.915479
    - Standard Deviation (Std Dev): 0.6297893
    - Standard Error of Mean (Std Err Mean): 0.2571104
    - Lower 95% Confidence Interval: -1.576402
    - Upper 95% Confidence Interval: -0.254556

  - **Lotion:**
    - Number: 6
    - Mean: 0.2225703
    - Std Dev: 0.7306505
    - Std Err Mean: 0.2982868
    - Lower 95% CI: -0.5442
    - Upper 95% CI: 0.989341

  - **Spray 1:**
    - Number: 6
    - Mean: 0.0804044
    - Std Dev: 0.6380284
    - Std Err Mean: 0.260474
    - Lower 95% CI: -0.589165
    - Upper 95% CI: 0.749741

  - **Spray 2:**
    - Number: 6
    - Mean: -0.30336
Transcribed Image Text:**Oneway Anova Analysis** The image displays the results of a one-way ANOVA test, which is used to compare the means of different groups to determine if there are any statistically significant differences among them. **Analysis of Variance Table:** - **Source:** - **Group:** - Degrees of Freedom (DF): 3 - Sum of Squares: 4.658577 - Mean Square: 1.55286 - F Ratio: 3.5813 - Prob > F: 0.0320* - **Error:** - DF: 20 - Sum of Squares: 8.672101 - Mean Square: 0.43361 - **C. Total:** - DF: 23 - Sum of Squares: 13.330678 The probability value (Prob > F) is 0.0320, indicating that there is a statistically significant difference among the group means at the 5% significance level. **Means and Standard Deviations:** - **Level:** - **Cream:** - Number: 6 - Mean: -0.915479 - Standard Deviation (Std Dev): 0.6297893 - Standard Error of Mean (Std Err Mean): 0.2571104 - Lower 95% Confidence Interval: -1.576402 - Upper 95% Confidence Interval: -0.254556 - **Lotion:** - Number: 6 - Mean: 0.2225703 - Std Dev: 0.7306505 - Std Err Mean: 0.2982868 - Lower 95% CI: -0.5442 - Upper 95% CI: 0.989341 - **Spray 1:** - Number: 6 - Mean: 0.0804044 - Std Dev: 0.6380284 - Std Err Mean: 0.260474 - Lower 95% CI: -0.589165 - Upper 95% CI: 0.749741 - **Spray 2:** - Number: 6 - Mean: -0.30336
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