Warm Up The table below shows data on the number of live births per 1000 women (aged 15-44 years) from 1965 to 2005. (Hint: enter the year as the years since 1900: 65, 70, …) Year Births Year Births 1965 19.4 1990 16.4 1970 18.4 1995 14.8 1975 14.8 2000 14.4 1980 15.9 2005 14.0 1985 15.6 1) Find the equation of the LSRL, r and r2. 2) Check to see if a linear model is appropriate. Explain. 3) Estimate the birth rate in 1997. 4) The actual rate in 1997 was 15.0. What is its residual?

Computer Output Data is often presented in a summary form of a computer program output. For the warm up problem we might get the following: ------------------------------------------------------------------- Dependent variable is: Births R squared = 67.43% S = 1.05   Variable Coefficient SE(Coeff) t-ratio p-value Constant 25.345 9.9004 2.56 0.0158 Year -0.1103 0.0289 -3.81 <0.0001 -------------------------------------------------------------------- What is the LSRL and r? What is the predicted number of births in 1972?

Practice Assembly line workers were studied to find a correlation between experience (in months) of the worker and the time (in minutes) to complete an assembly task. The data is summarized below. Dependent variable is: Assembly time R squared = 62.0% S = 9.790   Variable Coefficient SE(Coeff) t-ratio p-value Constant 84.683 5.602 15.12 0.000 Experience -0.30411 0.04963 -6.13 0.000 -------------------------------------------------------------------- What is the LSRL and r? What is the predicted assembly time for a worker with 120 months of experience?

Bears The following data on black bear age and weight came from a Canadian study completed in 2008. Age Weight (kg) Age Weight (kg) 10.5 54 6.5 62 6.5 40 5.5 42 28.5 62 7.5 40 10.5 51 11.5 59 6.5 55 9.5 51 7.5 56 5.5 50 a) Make a scatterplot. b) Find the equation of the LSRL and the correlation r. c) Is there an influential point? Check by removing the outlier and calculating the LSRL and r again.