QNT 561 Final Exam

2. Based on the scale of measurement for each variable listed below, which measure of central tendency is most appropriate for describing the data?

(21) You took a sample of size 21 from a normal distribution with a known standard deviation, . In order to find a 90% confidence interval for the mean, You need to find.

4. Calculate the following measures of central tendency for the set of cube measurement data. Show your work or explain your procedure for each.

5. Give the standard deviation for the mean and median column. Compare these and be sure to identify which has the least variability?

1. By hand, compute the mean, median, and mode for the following set of 40 reading scores:

If John gets an 90 on a physics test where the mean is 85 and the standard deviation is 3, where does he stand in relation to his classmates? (he is in the top 5%, he is in the top 10%, he is in the bottom 5%, or bottom 1%)

Standard Deviation for the mean column is 0.476Standard Deviation for the median column is 0.754Standard deviation for the mean column has least variability

Topics Distribution of the sample mean. Central Limit Theorem. Confidence intervals for a population mean. Confidence intervals for a population proportion. Sample size for a given confidence level and margin of error (proportions). Poll articles. Hypotheses tests for a mean, and differences in means (independent and paired samples). Sample size and power of a test. Type I and Type II errors. You will be given a table of normal probabilities. You may wish to be familiar with the follow formulae and their application.

Question 4: The mode is the most frequently occurring value in a set of data so here the mode is 178 so the answer is e.

2. Quantitative because the data given is concrete and generalizations like mean and mode can easily be identified.

(a). Plot mean chart (x-chart) and range chart (R-chart) to analyze these data. Sample No. Observations Mean Range

The mean, average of the population, the standard deviation, deviation in the sample, and a histogram, a graph to show the percentage of the population, was prepared. The means calculated as follows: blue 0.2072, orange 0.2271, green 0.1852, yellow 0.1165, red 0.1448, and brown 0.1192. The histogram was bell shaped with three outliers, numbers outside the given range, of 55 candies, or one bag.

The median is the midpoint of all variables in an observation that are organized from “smallest to largest” (110). In a situation where the median

5. The arithmetic mean is only measure of central tendency where the sum of the deviations of each value from the mean will always be zero

Which is valid where n0 is the sample size, Z2 is the abscissa of the normal curve that cuts off an area at the tails (1 - equals the desired confidence level, e.g., 95%)1, e is the desired level of precision, p is the estimated proportion of an attribute that is present in the population, and q is 1-p. The value for Z is found in statistical tables which contain the area under the normal curve.