According to 2010 UCR data, Oakland, CA has a murder rate of 22.0 (per 100,000) in 6th place, Washington, DC has a murder rate of 21.9 in 7th place, and Kansas City, MO has a murder rate of 21.1 in 8th place. If we looked at all U.S. cities with a population of 250,000 and converted their murder rates into z-scores in what order would Oakland, Washington, and Kansas City fall after the conversion? Explain your reason for this.

To determine the order of the cities after converting their murder rates into z-scores, we need to understand what a z-score represents. A z-score (also known as a standard score) measures the number of standard deviations a data point is from the mean of a distribution. It allows us to compare data points from different distributions by standardizing them.

To convert the murder rates into z-scores, we need to know the mean and standard deviation of the population of cities with a population of 250,000. Unfortunately, this information is not provided in the question.

However, we can still make an educated guess by assuming a normal distribution of murder rates among these cities. We will use the given data points of Oakland, Washington, and Kansas City to estimate the z-scores relative to each other.

Let's assume the mean of the population is 20 and the standard deviation is 2 (these values are arbitrary and solely used for illustrative purposes).

1. Calculate the z-score for Oakland:
z-score = (x - mean) / standard deviation
z-score = (22 - 20) / 2
z-score = 1

2. Calculate the z-score for Washington:
z-score = (x - mean) / standard deviation
z-score = (21.9 - 20) / 2
z-score ≈ 0.95

3. Calculate the z-score for Kansas City:
z-score = (x - mean) / standard deviation
z-score = (21.1 - 20) / 2
z-score ≈ 0.55

Based on these estimated z-scores, the order of the cities from highest to lowest is:
1. Oakland (z-score = 1)
2. Washington (z-score ≈ 0.95)
3. Kansas City (z-score ≈ 0.55)

Please note that these rankings are estimations based on assumed values for the mean and standard deviation. For a more accurate analysis, it is necessary to have the actual mean and standard deviation of the population.

Z = (score-mean)/SD

Need mean and standard deviation for ALL CITIES to find Z scores.