The price per share of stock for a sample of 25 companies was recorded at the beginning of a given year and then again at the end of the 1st quarter of that year. How stocks perform during the 1st quarter is an indicator of what is ahead for the stock market and the economy. Use the sample data given below to answer the following. Company | End of 1st Quarter | Beginning of Year | Company | End of 1st Quarter | Beginning of Year Company A | 25.13 | 19.91 | Company N | 45.98 | 33.25 Company B | 38.01 | 37.36 | Company O | 68.21 | 66.71 Company C | 53.9 | 45.78 | Company P | 39.23 | 40.12 Company D | 59.42 | 62.03 | Company Q | 70.12 | 62.00 Company E | 65.96 | 65.58 | Company R | 41.27 | 41.56 Company F | 108.48 | 105.94 | Company S | 33.26 | 25.96 Company G | 29.01 | 23.71 | Company T | 74.01 | 69.97 Company H | 11.45 | 10.71 | Company U | 69.06 | 54.70 Company I | 43.41 | 41.22 | Company V | 86.73 | 84.76 Company J | 21.07 | 17.91 | Company W | 21.65 | 21.64 Company K | 30.23 | 30.24 | Company X | 29.16 | 25.58 Company L | 20.15 | 18.08 | Company Y | 107.21 | 106.40 Company M | 49.31 | 42.04 | (a) Let di denote the change in price per share for company i where di = price per share at the end of the 1st quarter of the given year minus price per share at the beginning of that year. Use the sample mean of these values to estimate the dollar amount a share of stock has changed during the 1st quarter. (Round your answer to two decimal places.) $ (b) What is the 95% confidence interval (in dollars) estimate of the population mean change in the price per share of stock during the first quarter? (Use end of first quarter - beginning of year. Round your answers to two decimal places.) $ to $
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\[ \begin{array}{ll} \text{Company A:} & 25.13 - 19.91 = 5.22 \\ \text{Company B:} & 38.01 - 37.36 = 0.65 \\ \text{Company C:} & 53.90 - 45.78 = 8.12 \\ \text{Company D:} & 59.42 - 62.03 = -2.61 \\ \text{Company E:} & 65.96 - 65.58 = 0.38 \\ \text{Company F:} & Show more…
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Sri K.
Suppose the price per share of stock for a sample of 25 companies was recorded at the beginning of the first financial quarter and then again at the end of the first financial quarter. How stocks perform during the first financial quarter is an indicator of what is ahead for the stock market and the economy. Company End of 1st quarter Beginning of 1st quarter Company 1 58.69 59.32 Company 2 60.20 82.52 Company 3 107.07 114.50 Company 4 84.45 89.08 Company 5 130.51 144.73 Company 6 137.23 141.28 Company 7 36.56 46.57 Company 8 55.41 58.54 Company 9 39.90 41.94 Company 10 18.55 23.48 Company 11 37.04 44.04 Company 12 49.33 44.36 Company 13 189.13 193.53 Company 14 113.28 113.45 Company 15 76.46 96.15 Company 16 53.32 59.03 Company 17 40.70 47.73 Company 18 83.57 90.18 Company 19 99.50 91.45 Company 20 47.09 51.09 Company 21 55.32 70.70 Company 22 81.45 90.53 Company 23 50.77 49.99 Company 24 50.45 52.13 Company 25 134.36 133.08 (a) Let di denote the percentage change in price per share for company i where di = (end of 1st quarter price per share - beginning of 1st quarter price per share) / beginning of 1st quarter price per share. Use the sample mean of these values to estimate the percentage change in the stock price over the first quarter. (Round your answer to one decimal place.) % (b) What is the 95% confidence interval estimate of the population mean percentage change in the price per share of stock during the first quarter? (Round your answers to one decimal place.) % to % Interpret this result. Because the 95% confidence interval is completely below zero, we can be 95% confident that the population mean percentage change in the price per share of stock is negative.
Umar Sohail Q.
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