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Exercise

Assessing the growth rate

To compute the growth rate, you can do a linear regression of the logarithm of the total bacterial area versus time. Compute the growth rate and get a 95% confidence interval using pairs bootstrap. The time points, in units of hours, are stored in the numpy array t and the bacterial area, in units of square micrometers, is stored in bac_area.

Instructions

100 XP
  • Compute the logarithm of the bacterial area (bac_area) using np.log() and store the result in the variable log_bac_area.
  • Compute the slope and intercept of the semilog growth curve using np.polyfit(). Store the slope in the variable growth_rate and the intercept in log_a0.
  • Draw 10,000 pairs bootstrap replicates of the growth rate and log initial area using dcst.draw_bs_pairs_linreg(). Store the results in growth_rate_bs_reps and log_a0_bs_reps.
  • Use np.percentile() to compute the 95% confidence interval of the growth rate (growth_rate_bs_reps).
  • Print the growth rate and confidence interval to the screen. This has been done for you, so hit 'Submit Answer' to view the results!