Statistics homework - Speech or Presentation Example

ations, two standard deviations around arithmetic mean approximately cover 95% observations, 3 standard deviations around arithmetic mean approximately cover 99.7 % observations. A point estimate is based on a single estimated value of a parameter. Using the sample estimate, we can find the estimator by following any method of estimation. If we are encountering the situation of a biased data, a single Point-Estimate can falsify the analysis, so it is better to mention range as the actual population parameter value because if an estimate is given in terms of a range; it can absorb a little bias of the collected data.

On the other hand, the range of interval can be increased by increasing the confidence level. It is better to comment on how much runs any player can make in a particular over in terms of a range rather than claiming a definite value. OR, whenever newly hired employees are being asked about the expected salary, majority prefers to state the expectation as a range instead of a single solid figure. For a given confidence interval a a population mean can be found by , therefore the margin of error is , which simply indicates that bigger the sample size smaller will be the confidence interval.

Increased sample size always results in smaller limit using the same confidence level (1-α). If the average amount of soft-drink in n=30 bottles is 248ml with the standard deviation = 2ml, then the possible 95% confidence interval for the average amount for all such bottles could be; 247.28 and 248.72. On the other hand, if we want to measure the confidence interval for 100 such bottles using the same formula, it will be 247.608 and 248.392. Confidence interval seems shrunk with increased sample