The Boss wants your team to collect data to establish a confidence interval for a situation at work.

Full Answer Section

     

4. Calculate the margin of error. The margin of error is a measure of the uncertainty in the sample estimate. It is calculated using the sample statistic, the sample size, and the confidence level.
5. Construct the confidence interval. The confidence interval is a range of values that is likely to include the true population parameter. It is calculated by adding and subtracting the margin of error from the sample statistic.
6. Interpret the confidence interval. The confidence interval tells you how confident you can be that the true population parameter is within a certain range of values. For example, if you have a 95% confidence interval for the average customer satisfaction rating, you can be 95% confident that the true average rating is within the range of values specified by the confidence interval.

Here is an example of how to apply a confidence interval procedure at the workplace: Situation: Your boss wants to estimate the average number of sales calls made per day by all of the salespeople in the company. Step 1: The population parameter of interest is the average number of sales calls made per day by all of the salespeople in the company. Step 2: You collect a random sample of 100 salespeople and record the number of sales calls that each salesperson made on a given day. Step 3: You calculate the sample mean number of sales calls per day to be 20. Step 4: You calculate the margin of error to be 2.5. Step 5: You construct the 95% confidence interval for the average number of sales calls per day to be 20 ± 2.5, or 17.5 to 22.5. Step 6: You interpret the confidence interval to mean that you can be 95% confident that the true average number of sales calls made per day by all of the salespeople in the company is between 17.5 and 22.5. Confidence interval procedures can be used to estimate a wide variety of population parameters at the workplace. For example, you can use confidence intervals to estimate the following:

• The average customer satisfaction rating
• The percentage of employees who are satisfied with their jobs
• The average number of sales calls made per day
• The average amount of time spent on customer service calls
• The average number of defects in a product

Confidence interval procedures are a valuable tool for making informed decisions at the workplace. By using confidence intervals, you can estimate population parameters with a known degree of uncertainty. This information can be used to identify areas where improvement is needed, to set goals, and to track progress over time.  

Sample Answer

   

1. Identify the population parameter of interest. What do you want to estimate about the population? For example, you might want to estimate the average customer satisfaction rating, the percentage of employees who are satisfied with their jobs, or the average number of sales calls made per day.

2. Collect a random sample of data from the population. The sample should be large enough to be representative of the population, but not so large that it is too expensive or time-consuming to collect.

3. Calculate the sample statistic for the parameter of interest. For example, if you are estimating the average customer satisfaction rating, you would calculate the average rating for the sample of customers.