Question

Household income The $2015$American Community Survey estimated the median

household income for each state. According to ACS, the $90\%$confidence interval for the $2015$median household income in Arizona is $\backslash (51,492\pm \backslash )431$.

a. Interpret the confidence interval.

b. Interpret the confidence level.

Short answer

a. There is $90\%$assurance that income in Arizona fall between $\$51061\text{and}\$51923$

b. It is used for the calculation of value of level of significance

Step-by-step solution

Given Information

The confidence interval is given as$51,492\pm 431=(51061,51923)$for$90\%$.

To interpret Confidence Interval

Confidence Interval is calculated as $51,492\pm 431=(51061,51923)$

It implies that there is $90\%$assurance that Arizona's median household income falls between$\$51061\text{and}\$51923.$

Interpreting Confidence Level

• It gives the probability for values that expects to calculate population parameter.
• It is used for the calculation of value of level of significance$\alpha$.