University of South Carolina, Arnold School of Public Health, Dept. of Health Services Policy and Management, HSPM J716

Assignment 2 Answer Checker


Clinic 1

Let's first check your slope and intercept estimates for your least squares line for clinic 1. Wrong answers here indicate that
  1. there was an error in your Assignment 1 spreadsheet, or
  2. you didn't add the new rows correctly, or
  3. you typed in the clinic 1 data incorrectly.

For this answer checker, and for the write-up you hand in, round off the slope and intercept to the nearest integer (whole number). This applies to all three clinics.

What is the slope of your least squares line for clinic 1?

What is the intercept of your least squares line for clinic 1?

If those are both OK, let's test the goodness of fit statistics. Problems here indicate errors in the right half of your spreadsheet.

Is your R-squared between 0.0 and 1.0?

For the next two questions, your answer should have a decimal point and at least two numbers after the decimal point.

What is your t value? This is under the "t coeff=0" label in your spreadsheet.

To test the hypothesis that the true slope is 0, you compare your t value with a critical value that you find in the proper column and row in the t table. What is that critical value?

What is your prediction, based on the least squares line, for clinic 1 for the next month, month=12?

Round off your prediction to the nearest integer. This applies to all three clinics.

If everything is correct to this point, your spreadsheet is good. All you have to do for Clinic 2 is to type or paste its visit data on top of the data for Clinic 1. The spreadsheet will recalculate, and you will have your numbers for Clinic 2.

Clinic 2

Let's check the results of your least squares regression for clinic 2:
Type the results requested for clinic 2 in the small boxes. After typing, press Enter while you're in each box.

Clinic 3

For Clinic 3, type or paste its visit data on top of the data for Clinic 2. The spreadsheet will again recalculate, and you will have your numbers for Clinic 3.

Let's check the results of your least squares regression for clinic 3:
Type the results requested for clinic 3 in the small boxes. After typing, press Enter while you're in each box.

Prediction confidence interval Scroll down for help with this

What is the upper end of your prediction confidence interval?

What is the lower end of your confidence interval?

If you're having trouble with the prediction confidence interval, try these ideas:

Thanks for using the answer checker!


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