Solved:Fit an AR(1) to xt using maximum likelihood (basically unconditional least squares) as in Section 3.6. The easiest way to do this is to use sarima from astsa. Comment on the significance of the regression parameter estimates of the model. What is the estimate of the white noise variance.

 ARIMA models (including improved diagnostics) in a short command. It can also be used to perform regression with autocorrelated errors. This is a front end to arima () with a different back door.  

Usage Regression coefficients represent the mean change in the response variable for one unit of change in the predictor variable while holding other predictors in the model constant. .

Explanation: White noise refers to a statistical model for signals and signal sources, rather than to any specific signal. White noise draws its name from white light.

answer; /// i believe that the correct answer is(

there are treatment options for depression (mdd) that may work for you. one way of treating depression may be to affect the levels of certain chemicals that brain cells use to communicate, called neurotransmitters. scientists believe that certain neurotransmitters may be out of balance in depression.

although the exact way depression medications shown to ease overall depression symptoms in some people work is unknown, scientists think that some medications work by affecting the levels of a neurotransmitter called serotonin in the brain. other treatments work by affecting the levels of other neurotransmitters like norepinephrine or dopamine.