1. Warm Up
A 2007 study investigated a possible link between declining bird populations and electromagnetic radiation. It looked at sparrow density (per hectare) vs. field strength (V/m) at 14 randomly selected locations. Field Sparrow Density Field Sparrow Density Is this convincing evidence of a negative correlation between field strength and sparrow density? Use the 4 step process but assume the conditions are met.

2. Warm Up – Computer Output
Often linear regression problems will provide results from a “statistical computer program” for analysis instead of raw data. The data for the warm up problem is shown below R squared = 73.1% S = Variable Coef SE Coef T P Constant EM Field

3. Practice #1
A 2005 study compared the survival rate of grouse offspring to the density of vegetation in the nest area. A random sample of 23 nests were compared. Computer output of the regression analysis is shown R squared = 19.4% S = Variable Coef SE Coef T P Constant Veg Density )Find the LSRL and the correlation coefficient. 2) Calculate the 90% confidence interval for the slope.(assume all conditions for inference are met)

4. Practice #2
A 2008 study compared the oxygen concentration in seawater to the number of shrimp caught in a tow line. A random sample of 10 catches were compared. Computer output of the regression analysis is shown R squared = 49.6% S = Variable Coef SE Coef T P Constant O2 Conc ) Construct a 99% confidence interval for the slope. 2) Construct a linear regression t test for evidence of a positive correlation with a = .05. Assume conditions are met for both procedures.