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A confidence interval for your CDC sample

mark

(10 pts)

In this problem, you’re going to use our Data Explorer to help you write down a couple confidence intervals for height. To get started, download your data set after choosing your name from this list:

Once you have your data, upload it to our Data Explorer. Then, use that to find the mean, standard deviation, and sample size of your data. With that information,

  • Find the standard error associated with your sample,
  • Find the margin of error for a 95% level of confidence,
  • Express your confidence interval in the form
[\bar{x}-ME, \bar{x}+ME].
  • Do the same for a 99% level of confidence
audrey

My data had 110 individuals with a mean \bar{x} = 67.736 and a standard deviation s=4.176. Therefore, my standard error is

SE \approx s/\sqrt{n} = 4.176/\sqrt{110} = 0.398.

For a 95% confidence interval, I need a z^* multiplier of 2 to get

ME = 2\times0.398 = 0.796.

Thus, my confidence interval is

[67.736 - 0.796, 67.736 + 0.796] = [66.94, 68.532].

For a 99% level of confidence, the [normal calculator indicates that I need a z^* multiplier of 2.576. Thus, my margin of error is now

ME = 2.576\times0.398 = 1.02525

and myconfidence interval is

[67.736 - 1.02525, 67.736 + 1.02525] = [66.7108, 68.7613].

Here’s what I typed to produce this:

My data had 110 individuals with a mean $\bar{x} = 67.736$ and a standard deviation $s=4.176$. Therefore, my standard error is
$$
SE \approx s/\sqrt{n} = 4.176/\sqrt{110} = 0.398.
$$
For a 95% confidence interval, I need a $z^*$ multiplier of 2 to get
$$
ME = 2\times0.398 = 0.796.
$$
Thus, my confidence interval is
$$
[67.736 - 0.796, 67.736 + 0.796] = [66.94, 68.532].
$$
For a 99% level of confidence, the [normal calculator indicates that I need a $z^*$ multiplier of $2.576$. Thus, my margin of error is now
$$
ME = 2.576\times0.398 = 1.02525
$$
and myconfidence interval is
$$
[67.736 - 1.02525, 67.736 + 1.02525] = [66.7108, 68.7613].
$$
jnilsen

My data had 122 individuals with a mean \bar{x} = 67.62295081967213 and a standard deviation s=4.04995228795987. Therefore, my standard error is

SE \approx s/\sqrt{n} = 4.04995228795987/\sqrt{122} = 0.3667.

For a 95% confidence interval, I need a z^* multiplier of 2 to get

ME = 2\times0.3667 = 0.733.

Thus, my confidence interval is

[67.623 - 0.733, 67.623 + 0.733] = [66.89, 68.356].

For a 99% level of confidence, the [normal calculator indicates that I need a z^* multiplier of 2.576. Thus, my margin of error is now

ME = 2.576\times0.3667 = 0.9446

and myconfidence interval is

[67.623 - 0.9446, 67.623 + 0.9446] = [66.7784, 68.5676].
shumpher

My data had 111 individuals with a mean \bar{x} = 67.630 and a standard deviation s=3.849. Therefore, my standard error is

SE \approx s/\sqrt{n} = 3.849/\sqrt{111} = 0.365.

For a 95% confidence interval, I need a z^* multiplier of 2 to get

ME = 2\times0.365 = 0.73.

Thus, my confidence interval is

[67.630 - 0.73, 67.630 + 0.73] = [66.9, 68.36]

For a 99% level of confidence, the normal calculator indicates that I need a z^* multiplier of 2.576. Thus, my margin of error is now

ME = 2.576\times0.365 = 0.94

and myconfidence interval is

[67.630 - 0.94, 67.630 + 0.94] = [66.69, 68.57].
dchaney

My data had 118 individuals with a mean \bar{x} = 67.407 and a standard deviation s=3.844. Therefore, my standard error is
SE \approx s/\sqrt{n} = 3.844/\sqrt{118} = 0.353.
For a 95% confidence interval, I need a z^* multiplier of 2 to get
ME = 2\times0.353 = 0.706.
Thus, my confidence interval is
[67.407 - 0.706, 67.407 + 0.706] = [66.701, 68.113].
For a 99% level of confidence, the [normal calculator indicates that I need a z^* multiplier of 2.576. Thus, my margin of error is now
ME = 2.576\times0.353 = 0.909
and myconfidence interval is
[67.407 - 0.909, 67.407 + 0.909] = [66.498, 68.316].

afloyd2

My data had 93 individuals with a mean \bar{x} = 66.89 and a standard deviation s=4.434. Therefore, my standard error is

SE \approx s/\sqrt{n} = 4.434/\sqrt{93} = 0.4598.

For a 95% confidence interval, I need a z^* multiplier of 2 to get

ME = 2\times0.4598 = 0.9196.

Thus, my confidence interval is

[66.89 - 0.9196, 66.89+ 0.9196] = [65.97, 67.81].

For a 99% level of confidence, the [normal calculator indicates that I need a z^* multiplier of 2.576. Thus, my margin of error is now

ME = 2.576\times0.4598 = 1.1843

and myconfidence interval is

[66.89 - 1.184325945, 66.89 + 1.184325945] = [65.71, 68.07].
ksimmon1

My data had 103 individuals with a mean \bar{x} = 67.83495145631068 and a standard deviation s=4.2173709108378405. Therefore, my standard error is

SE \approx s/\sqrt{n} = 4.2173709108378405/\sqrt{103} = 0.41554990353

For a 95% confidence interval, I need a z^* multiplier of 2 to get

ME = 2\times 0.41554990353 = 0.83109980706.

Thus, my confidence interval is

[67.83495145631068 - 0.83109980706, 67.83495145631068 + 0.83109980706] = [67.0038516493, 68.6660512634].

For a 99% level of confidence, the [normal calculator indicates that I need a z^* multiplier of 2.575829. Thus, my margin of error is now

ME = 2.575829\times 0.41554990353= 1.07038549246

and my confidence interval is

[67.83495145631068 - 1.07038549246, 67.83495145631068 + 1.07038549246] = [66.7645659639, 68.9053369488].
snichol3

my data had 100 individuals. mean = 67.495 standard deviation = 3.764

SE = 3.764/10 = 0.3764
95% CONFIDENCE INTERVAL Z* OF 2 =
ME = 2X0.376 = 0.753
CONFIDENCE INTERVAL = {67.495 - 0.753,67.495+0.753} = {66.742, 67.248}
99% CONFIDENCE LEVEL Z* = 2.576
ME = 2.576 X 0.376 = 0.968
CONFIDENCE INTERVAL = {67.495-0.968,67.495+0.968} = {66.527, 68.463}

hfryzowi

My data had 96 intervals with a mean of 67.364 and a standard deviation s= 4.255.
Therefore, my standard error is
SE= 4.176/ 96 = 0.434

For a 95% confidence level I need a z* multiplier of 2 to get

                                        ME= 2 x 0.434 = 0.868

Thus, my confidence interval is

                                   [67.364 - 0.868, 67.364 + 0.868] = [66.496, 68.232]

For a 99% level of confidence, the normal calculator indicates that I need a z* multiplier of 2.575. Thus my margin of error is now

                                  ME= 2.575 x 0.434 = 1.11755

and my confidence interval is

                                 [67.364 - 1.11755, 67.364 + 1.11755] = [66.24645, 68.48155]
ewalsh3

My data had 95 individuals with a mean of 67.726 and a standard deviation s = 4.1242.

Therefore my standard error is 0.398

For a 95% confidence interval I have a ME of 0.796
So my confidence interval is [66.94, 68.5832]

For a 99% confidence interval I have a ME of 1.02525
So my confidence interval is [66.7108, 68.7613]

My data had 95 individuals with a mean \bar{x} = 67.72631578947369 and a standard deviation s=4.124246172934007. Therefore, my standard error is

SE \approx s/\sqrt{n} = 4.176/\sqrt{110} = 0.398.

For a 95% confidence interval, I need a z^* multiplier of 2 to get

ME = 2\times0.398 = 0.796.

Thus, my confidence interval is

[67.736 - 0.796, 67.736 + 0.796] = [66.94, 68.532].

For a 99% level of confidence, the [normal calculator indicates that I need a z^* multiplier of 2.576. Thus, my margin of error is now

ME = 2.576\times0.398 = 1.02525

and myconfidence interval is

[67.736 - 1.02525, 67.736 + 1.02525] = [66.7108, 68.7613].
ekrans

My data had 98 individuals with a mean \bar{x} = 67.612 and a standard deviation s=4.017. Therefore, my standard error is

SE \approx s/\sqrt{n} = 4.017/\sqrt{98} = 0.406.

For a 95% confidence interval, I need a z^* multiplier of 2 to get

ME = 2\times0.406 = 0.812.

Thus, my confidence interval is

[67.612 - 0.796, 67.736 + 0.796] = [66.94, 68.532].

For a 99% level of confidence, the [normal calculator indicates that I need a z^* multiplier of 2.576. Thus, my margin of error is now

ME = 2.576\times0.406 = 1.045856

and my confidence interval is

[67.612 - 1.045856, 67.612 + 1.045856] = [66.5661, 68.6579].
atweed

My data had 87 individuals with a mean \bar{x} = 67.1264 and a standard s = 4.1758

The standard error associated with my sample is; SE \approx s / \sqrt {n} = 4.1758 / \sqrt {87}= 0.44769
For a 95% confidence level my Margin of error is; ME = 2 \times 0.44769 = 0.895385

My confidence interval is; [67.1264- 0.895385, 67.1264+ 0.895385]=[66.2310, 68.0217]

For a 99% confidence level my Margin of error is now; ME= 2.576 \times 0.44769= 1.1552

As well as my confidence level is now; [67.1264- 1.1552, 67.1263+ 1.1552]= [65.9712, 68.2816]

tcunnin1

Here’s what I typed to produce this:

My data had 111 individuals with a mean \bar{x} = 67.342 and a standard deviation s=4.137. Therefore, my standard error is

SE \approx s/\sqrt{n} = 4.137/\sqrt{110} = 0.3927.

For a 95% confidence interval, I need a z^* multiplier of 1.76 to get

ME = 1.76\times0.3927 = 0.7696.

Thus, my confidence interval is

[67.342 - 0.7696, 67.342 + 0.7696] = [66.5724, 68.1116].

For a 99% level of confidence, the [normal calculator indicates that I need a z^* multiplier of 2.5758. Thus, my margin of error is now

ME = 2.5758\times0.39270 = 1.0115

and myconfidence interval is

[67.342 - 1.0115, 67.342 + 1.0115] = [66.3305, 68.3535].
jmillspa

My data set had 84 observations with a mean of 66.845, and a standard deviation of 4.309

for 95% confidence my SE =(4.309/9.165)=.470 ME = (.470*2) = .940 therefore my confidence interval is (66.845-.94,66.845+.94) = (65.905,67.785)

for a 99% confidence interval my z multiplier is 2.576
so (.470*2.756 =1.211) ME = 1.211 and my confidence interval is = (66.845-1.211,66.845+1.211) or = (65.634,68.056)

mark