• How many raisins are in a 1/2 oz. box of SUN-MAID raisins?  How do you estimate it?  Is receiving more number of raisins a better quality or is receiving a less number of raisins a better quality?
• Give your best guess.  Then count the number of raisins in the 1/2 oz. box you are given.
• Your class is given a random sample of SUN-MAID raisins.  You are asked to estimate the population average number of raisins using a sample of n boxes.

• Have your class participate in the data collection activity (go to step 3)

                                 OR         

• Use the data collected by other classes (go to step 4)

1. Distribute the raisins to the students and ask them to guess the number of raisins.  Have them write down their guess on a piece of paper before counting.
2. Ask students to count the number of raisins and have them write down the actual number.
3. Direct students to the "Data Entry" page to add their data, their guess and their actual count.
4. To get to the "Add Data" page click on "Data Entry," select Activity Raisins and click on "Add Data".
5. You should now provide the activity pass code to the students.

• There are several criteria available for selecting either all of the data or a subset of all the data available.  Ask students to follow your instructions as to what data is to be selected and where it should be saved (an easy way is to save it is on Desktop).

• You may use the software in your local computer lab.
• You may use the online analysis tool, "statcrunch" at http://www.statcrunch.com/  For first time users you need to sign onto the "statcrunch" website.  Please ask students to write down their user ID and password for future use.
• Direct students to input the data and analyze the data.  Be more specific on what tools to be sued for analyzing this data based on the purpose of the activity.

Suggested Questions for Classroom Activities

• Focus on the context.
• Engage students to discuss the difference between guesses and actual counts.
• Engage students to review the descriptive techniques (histograms, outliers, variations and numerical summaries).
• Engage students to connect the sampling distribution of sample mean with the concept of estimation through bias and precision. 
  Unbiasness: The center of the distribution of sample mean is the same as the population mean.
  Precision: Degree of how close when using sample mean to estimate the unknown population mean.  It is measured by using standard error (SE) of mean.
       -Point out that common experience suggests larger
        random sample tends to give a better estimate of
        population mean and it is measured by SE of mean =
        d/n
       -Have students discuss what the trend of the SE of
        the mean will be if we continue to increase sample
        size and eventually the sample will become the whole
        population.
• When addressing the margin of error or sample size, point out that newspapers often report statements about a survey such as "The % of favoring a casino in a city is 35% with margin of error ± 4%".  Begin the discussion on what the margin of error is, how to compute it and why it is important for determining sample size and how to determine sample size.