Physics 405

Homework assignment #3

Slightly modified exercise 4.12 from Bevington, and question 6.4 from Bevington. The questions are reproduced below.

4.12  Take the data that you used in HW #1, problem 1 (text or xls) , and the histogram you generated of the data in 5-point bin intervals. Plot a Gaussian curve based on the mean and standard deviation of the data, normalized to the area of the histogram.  Apply the chi-square test and check the associated probability from table C.4 in Bevington. (For a definition of the "chi-square" test, see section 4.3 of Bevington, or Taylor Chpt 12.)

6.4  Derive a formula for making a linear fit to data with an intercept at the origin so that y = bx. Apply your method to fit a straight line through the origin to the following set of data (text or xls).  Assume uniform uncertainties of si=2.0 in yi.  Find the reduced chi-squared for the fit and the uncertainty in b.  Note, do this problem analytically, i.e., do not use packaged fitting routines!  You may use a spreadsheet, but you must show the formulas for each column!