Notation

a. Identify the values of \(\mu \) and \(\sigma \) for the standard normal distribution.

b. What do the symbols \({\mu _{\bar x}}\) and \({\sigma _{\bar x}}\)represent?

Short Answer

Expert verified
  1. The symbols\(\mu \;{\rm{and}}\;\sigma \) represent the mean and standard deviation of population values respectively. Thus, \(\mu = 0,\;{\rm{and}}\;\sigma = 1\) for standard normal distribution.
  1. The symbols\({\mu _{\bar x}},{\sigma _{\bar x}}\)represent the mean and standard deviation of all the sample mean values of a specific sample size respectively.

Step by step solution

01

Given information

Certain notations are mentioned.

02

Describe the random variablefor population

a.

Let X be the random variable for population of all observations, which follows standard normal distribution.

The mean of the population is represented by \(\mu \). For standard normal distribution, mean is known to be 0.

The standard deviation of the population is represented by \(\sigma \). For standard normal distribution, standard deviation is known to be 1.

Thus, \(X \sim N\left( {\mu = 0,\sigma = 1} \right)\).

03

Describe the random variable for samples

b.

Let \(\bar X\) be the random variable for sample means of different equally sized samples taken from population.

The mean of the sample mean distribution is \({\mu _{\bar x}}\).

The standard deviation of sample mean distribution is \({\sigma _{\bar x}}\) .

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