Step $9-$ Confidence Intervals for the Average Relative Skill of All Teams in the Assigned Team's Years In $[4]$:

import numpy as np

import scipy.stats as stats

$\backslash$s Assuming the dataframe is Loaded as assigned$\_$years$\_$league$\_$df and contains the coluwn 'elo$\_$n$\text{'}$

$45$ Step $1$: Calculate the mean and standard deviation of relative shilL $($ELO$)$ in years $1996-1998$

mean$\_$elo $=$ assigned$\_$years$\_$league$\_$df$[\text{'}$elo$\_$n$\text{'}],$mean$()$

std$\_$elo $=$ assigned$\_$years$\_1$eague$\_$df$[\text{'}$elo$\_$n$\text{'}].$std$()$

Step $2$: Calculate n$,$ the sample stze

n $=$ assigned$\_$years$\_$league$\_$df$[\text{'}$elo$\_$n$\text{'}].$count$()$

$4\}\backslash$mathrm$\{$ Step $3$: Calculate the standard error

standard$\_$error $=$ std$\_$elo $/$ np$.$sqrt$($n$)$

Step $4$: Calculate the $95$x confidence interval

confidence$\_$level $=0\mathrm{.}95$

z$\_$score $=$ stats.norn.ppf$(1-(1-$ confidence$\_1$evel$)/2)$ I$\backslash$ z$-$score for $95\%$ confidence

margin$\_$of$\_$error $=$ z$\_$score $*$ standard$\_$error

confidence$\_$interval $=($mean$\_$elo $-$ margin$\_$of$\_$error, nean$\_$elo $+$ margin$\_$of$\_$error$)$

Print the results rounded to two decimal places

print$($f$*$Mean ELO: $\{$nean$\_$elo:$\mathrm{.}2$f$\}")$

print$($f$)$

print$($f$*$Sample Size: $\{$n$\}")$

print$($f$)$

print$($f$*95\%$ Confidence Interval: $(\{$confidence$\_$interval$[$e$]$:$\mathrm{.}2$f$\},\{$confidence$\_$interval$[1]$:$\mathrm{.}2$f$\})")$

NameError

Traceback $($most recent call last$)$

$6||$

The management also wants to you to calculate a $95\%$ confidence interval for the average relative skill of all teams in the years $1996-1998.$ Calculate this confidence interval.

You are to write this code block yourself.

Use Step $8$ to help you write this code block. Here is some information that will help you write this code block. Reach out to your instructor if you need help.

The dataframe for the years $1996-1998$ is called assigned$\_$years$\_$league$\_$df

The variable 'elo$\_$n$\text{'}$ represents the relative skill of teams.

Start by calculating the mean and the standard deviation of relative skill $($ELO$)$ in years $1996-1998.$

Calculate n that represents the sample size.

Calculate the standard error which is equal to the standard deviation of Relative Skill $($ELO$)$ divided by the square root of the sample size n$.$

Assuming that the population standard deviation is known, use Python methods for the Normal distribution to calculate the confidence interval.

Your statistics should be rounded to two decimal places.

Write your code in the code block section below. After you are done, click this block of code and hit the Run button above. Reach out to your instructor if you need more help with this step.