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Statistics Essay Example
 Category:Statistics
 Document type:Assignment
 Level:Undergraduate
 Page:1
 Words:454
Statistics 6

Normal distribution
In a research by Anderson (250), a normal distribution is a continuous, symmetric, and bellshaped distribution of a variable. Moreover, it has the same mean, median, and mode located at the center of the distribution. The distribution is also unimodal and continuous without gaps.
By looking at the descriptive statistics obtained in task 5, the mean, mode, and median is 583.41, 425.00, and 460.00 respectively. The three measures of central tendency are therefore not equal. Secondly, the sample has skewness of 2.48 showing that the sample is positively skewed. Thirdly, the distribution is heavy tailed as dictated by the kurtosis value 6.92. The conclusion therefore is that the data was not obtained from a normally distributed population.

Data values that lie within 1.5 standard deviations of the mean
Approximately
lie within 1.5 standard deviations of the mean.

Number of “Sold Price” that lie within 1.5 standard deviations
If
If
Through manually count, the “Sold Price” between 25.2 and 1141.62 are 44. There is a difference of approximately 3 from the calculated value in 4 above.

Descriptive statistics for “Sold Price” is tabulated below

Point estimate of the mean “Sold Price” is 583.41.

90% confidence interval estimate of the mean “Sold Price”
The Student t distribution will be used because the population standard deviation is unknown.

Based on the calculations above, we are 90% confident that the population mean of “Sold Price” lies between

The interval estimate obtained above is satisfactory because the actual value of 650 ($000s) is within the calculated 90% confidence interval of
.

99% confidence interval estimate of the mean “Sold Price”
Student tdistribution is applied since population standard deviation is not provided

From the calculations above, it is evident that confidence interval gets large as we increase the confidence level from 90% to 99%. This was anticipated because the level of preciseness will tend to decline as we become more confident that the interval actually contains the population mean. However, this can be avoided by increasing the size of the population.

Brick veneer properties

The point estimate of the proportion of brick veneer in the population is

99% confidence interval estimate of the proportion of brick veneer properties
In a study by Anderson (276), standard error is given as
Margin of error:
99% confidence interval:

From the calculations above, we are 99% confident that the proportion of brick veneer properties in the population lies between 23.29% and 60.71%.

Where the actual population proportion of brick veneer properties is actually 42%, the confidence interval estimate calculated in (a) is satisfactory. The rationale is that it lies within the confidence interval of
.
Works Cited
Anderson, David. Essentials of modern business statistics, Eagan, MN: Cengage SouthWestern, 2008.