Problem 1. A study of the density of stomata in vine leaves of different areas came up with the following results. Calculate the correlation coefficient r between these two variables and determine whether this is a significant correlation. What can you say about the relationship between leaf area and stomata density? Leaf area (mm²) 45 56 69 32 18 38 48 26 60 51 Stomata density (mm²) 36 28 27 39 56 37 32 45 24 31 State the Question: Biological Question Statistical Question Null Hypothesis: Biological Null Hypothesis Statistical Null Hypothesis Create a Visualization (attach as separate page) Calculate Test Statistic with Significant Value Draw an Inference
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Step 1: The question asks to calculate the correlation coefficient r between leaf area and stomata density and determine whether it is significant. Show more…
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21. (2 pts) Integrated plant biology: leaf stomatal density appears to be roughly correlated to the biome type a plant grows in. For instance, if a plant grows in a dry biome type it usually has low stomatal density whereas if it is found in a tropical rain forest biome it will have numerous stomata. Now, suppose you found a plant in the desert biome type that had higher than average (for desert plants) stomatal density. At first you might think your data collection was wrong but it was not! Therefore, what else could account for this result besides measurement error? In other words, is there any other anatomical feature of a plant that could compensate for a high number of stomata on its leaf so that water loss would not be too high? Please give one possible example and explain why it would help prevent water loss:
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Orange trees - In the 1960s, a botanist was conducting a research on orange trees. He wanted to figure out the relationship between the growth of trees and their ages. The botanist gathered a random sample of 35 orange trees and recorded the circumference of the tree in mm and the age of the tree in days. Circumference of tree is the X variable and Age of tree is the Y variable in this scenario. The summary statistics are given below: Variable: Circumference (X), Average: 114.5, Standard Deviation: 56.5 Variable: Age (Y), Average: 921, Standard Deviation: 490 The correlation coefficient between the variables X and Y is r = 0.89. What is the R^2 value for this regression model? Give your answer to 4 decimal places.
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