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I need help with this lab, please! I have attached all of the information.

Confidence Intervals A condence interval describes the uncertainty in an experimental measurement by identifying a range of values that are likely to be generated by similar experiments. Background In this experiment you will be briefly shown a display with airplane images. On each trial you will be asked to estimate the number of airplanes in the image. Being able to quickly make judgments of this type is important for some occupations, such as an air traffic controller. At the end of the experiment you will compute a confidence interval of the errors you make. The confidence interval provides an estimate of whether you overestimate or underestimate the number of airplanes (on average). If your estimates balance out above and below the true value, your mean would be zero. We are also interested in the spread of the condence interval,__sin_ce an air traffic controller needs to be accurate on essentially every trial (and notjust on average). Instructions If you have logged in, you will see a black outline rectangle below. Make sure that you can see the full area before you begin the lab. Start a trial by clicking the Start Next Trial button. Silhouette images of multiple planes will appear on the screen for one second and then disappear. You task is to estimate the number of planes. Move the slider knob to indicate your estimate. Click on the Submit choice button to fix your selection. At the end of the experiment, you will be asked if you want to save your data to a set of global data. After you answer the question, a new Web page window will appear that includes a debriefing, questions for you to answer, and your trial-bytrial data. Tablet Specic Details If you are using a tablet, tap the Start Next Trial button to begin a trial. Silhouette images of airplanes will be briefly presented. Use the slider to indicate the number of shown planes. When you feel the slider is appropriately placed, tap on the Submit choice button. Computer Specic Details If you are using a computer, click on the Start Next Trial button to begin a trial. Silhouette images of airplanes will be briefly presented. Use the slider to indicate the number of shown planes. When you feel the slider is appropriately placed, click on the Submit choice button. Lab Trials to go: 0 0 35 Start Next Trial Submit choice Would you like to add your data to the global data set? This is optional. Whatever you choose, STATLAB will save your individual data and record that you have completed the lab. Questions What methods did we employ in this experiment? On each trial, you briey saw a set of planes on the screen. Your task was to estimate how many planes were on each screen. Because the actual number of planes varies from trial to trial, we are interested in analyzing the errors you make across the trials. If you were accurate on a trial, the error would be zero. If you overestimate the number of planes, the error will be a negative number. If you underestimate the number of planes, the error will be a positive number. Thus, the closer your error is to zero, the better your average performance. In the analysis below, you will compute a mean of your error scores across the trials. We have to be careful about interpreting the value of a mean error. You could have a mean value close to zero in many different ways. It could be that on every trial your error is almost zero, so the mean is also close to zero. This would indicate that you are quite good at estimating the number of planes. However, a mean near zero could also occur by having some trials where you substantially overestimate the number of planes and other trials where you substantially underestimate the number of planes. In the calculation of the mean, these terms would produce a value near zero. This case would indicate that you are not very good at estimating the number of planes and that you are equally prone to overestimating and to underestimating the number. Clearly, the mean by itself is not sufcient to identify whether or not someone is good at estimating the number of planes or not. A better approach is to calculate a confidence interval. This identies the range of values where one can have condence that the true ability of the person exists. In our case, an air traffic controller should have a small condence interval, with a lower limit close to the upper limit, which is centered on zero. A poor estimator might have a mean of zero, but a larger confidence interval, which would indicate that the person is sometimes far from accurate on some trials. Formulas To calculate the condence internal you need to rst calculate the mean: X*:Zg,i,=1Xin,X=):L=1nXin, standard deviation (this is the raw score formula): s=EiX2i(21&)2n 1 J,s=ziXi2(zjgg92mn1, and standard error of the mean: sag=anw/s3su, Next, you need to identify the (\"critical value. This is most easily done with an online calculator, using df=n-1. Finally, compute the lower and upper limits of the condence interval: m**W.X*+W]-(X'ILf2&'X_+LQ2&_)- Answer the questions using the data below. You will often find it helpful to sort the data and calculate values using a spreadsheet such as Microsoft Excel, Sheets from Google apps, Open Ofce, or Numbers (Mac only). To import the data into a W select and copy all the cells in the trial-bytrial data table below and then paste them into an open page of the spreadsheet. Use the trialbytrial data to answer these questions. Question Answer Status Standard deviation of estimate for difference scores: ' Check Not yet answered (The difference between your answer and the answer Hint correctly correct value must be less than 0.01.) Degrees of freedom: our answer must exactl e ual the correct Check Hint (Y y q value.) answer Not yet answered correctly 0 Lower limit of the 95 A; condence interval: [01%]; Not yet answered (The difference between your answer and the lanswer H t correc tl correct value must be less than 0.01.) Y =-I- On each trial, you estimated the number of shown airplanes. The actual number of planes varied across trials. The nal column gives the difference between the actual number of planes and your estimate. Actual number Estimated number Difference between actual and Trlal of planes of planes estimated number of planes 1 13.0 14.0 -1.0 2 18.0 20.0 -2.0 3 9.0 10.0 -1.0 4 16.0 16.0 0.0 5 9.0 9.0 0.0 6 15.0 14.0 1.0 7 18.0 21.0 -3.0 8 15.0 15.0 0.0 9 22.0 22.0 0.0 10 21.0 21.0 0.0 11 14.0 12.0 2.0 12 21.0 20.0 1.0 13 17.0 18.0 -1.0 14 7.0 7.0 0.0 15 11.0 12.0 -1.0 16 22.0 24.0 -2.0 17 22.0 18.0 4.0 18 10.0 10.0 0.0 19 21.0 22.0 -1.0 20 20.0 18.0 2.0