最新電大開放教育專科市場調查與商情預測期末復習考試小抄(編輯修改稿)

　

【文章內容簡介】 觀察或實驗出現誤差，其關系值也不可能絕對固定，有時也通過相關關系來反映。 (2)相關關系的定量分析必須用函數表達式來近似地反映自變量與因變量之間的一般關系值。 ？ 答：隨機抽樣調查是從研究對象的總體中，按照隨機原則抽取一部分單位作為樣本進行調查，并用調查結果推斷總體。它具有以下特點：（ 1）抽取樣本的客觀性。（ 2）可以比較準確地推斷總體。（ 3）是一種比較節省的調查 方法。（ 4）應用范圍廣泛，特別適用于研究 市場現象的數量表現。 。 答：（ 1）根據預測目的，選擇和確定自變量和因變量。（ 2）確定回歸方程，建立預測模型。（ 3）對回歸模型進行檢驗，測定預測誤差。（ 4）用預測模型計算預測值，并對預測值作區間估計。 四、計算題 1．某市常住居民 55 萬戶，抽選 100 戶進行食糖需求量調查，得知樣本平均每戶年需求量為 12 公斤，樣本標準差為 4。根據上述資料，要求：(1)用單純隨機抽樣方式的重復抽樣公式，計算抽樣誤差。 (2)若置信度為 95%，試估計樣本置信區間，并推斷全市食糖需求量的置信區間。 2．某地區 2021～ 2021年水稻產量資料如下表： 試用最小平方法預測 2021 年水稻產量。（按直線趨勢法計算 ） 解：設直線方程為 Y=a+bt 列參數計算表為： 3．某市常住居民 70 萬人，抽選 1400人進行調查，得知人均年食糖需要量為 ，樣本方差為 ，根據上述資料，要求： (1)用單純隨機抽樣方式的重復抽樣公式，計算抽樣誤差。 (2)若置信度為 95％，試估計樣本年人均食糖需求量置信區間 ，并推斷全市食糖需求量置信區間。 4．某商場銷售額歷史資料如下： (單位：億元 ) 年 份 01 02 03 04 05 銷售額 試用最小平方法擬合直線方程，預測該商場 2021 年銷售額。 5．某市常住居民 16 萬戶，抽選 8000戶進行洗衣機普及率調查，得知樣本平均每百戶洗衣機保有量為 60 臺。根據上述資料，要求： （ 1）用單純隨機抽樣方式的重復抽樣公式，計算抽樣誤差。 （ 2）若置信度為 95％，試估計樣本置信區間，并推斷全市洗衣機保有量置信區間。 解：因為 n=8000 p=60% μ= 即 μ=% 又因為置信度為 95% 所以 t= Δ=tμ=% 所以樣本置信區間為： 60%177。% 即 %～ % 又因為 N=16 萬，所以該市居民年洗衣機保有量置信區間為： %16 ～ %16 即 94272～ 97728（臺） 6．某商場銷售額歷史資料如下：（單位：百萬元） 年份 03 04 05 06 07 銷售額 560 620 685 747 808 試用最小平方法擬合直線方程，預測該商場 2021 年銷售額。（要求列出參數計算表） 解：設直線方程為： Y=a+bt 列參數計算表為： 年份 ti yi tiyi ti2 03 2 560 1120 4 04 1 620 620 1 05 0 685 0 0 06 1 747 747 1 07 2 808 1616 4 Σ 0 3420 632 10 所以， a=684 b= 所以 Y=684+ 令 t=3 Y=684+3=( 百萬元 ) 7. 某縣有居民家庭 40000 戶，抽選 1600戶進行食糖需求量抽樣調查。調查結果，樣本平均每戶需要食糖 4 公斤，樣本標準差為 8。根據上述資料，要求： （ 1）用單純隨機重復抽樣的誤差計算公式，計算出抽樣誤差。 a=8 n=1600 181。x （ 2）設要求置信度為 95%，試估計該樣本戶平均食糖需求量置信區間。 因為置信度為 95%，所以 t= △ x =t181。x == 置信區間為： ～ 4+ 即 ～ （ 3）以樣本指標推斷該市居民全年食糖需求量的置信區間。 40000*～ 40000* 即： 144320～ 175680 （ 4）已知食糖銷售量的季節指數，第一季度為 108%，按上述食糖年人均需要量置信區間，估算出該市第一季度食糖需求量的置信區間。 (144320/4)*～ (175680/4)* ～ 請您刪除一下內容， O(∩ _∩ )O謝謝！！！ 2021年中央電大期末復習考試小抄大全，電大期末考試必備小抄，電大考試必過小抄 Basketball can make a true claim to being the only major sport that is an American invention. From high school to the professional level, basketball attracts a large following for live games as well as television coverage of events like the National Collegiate Athletic Association (NCAA) annual tournament and the National Basketball Association (NBA) and Women39。s National Basketball Association (WNBA) playoffs. And it has also made American heroes out of its player and coach legends like Michael Jordan, Larry Bird, Earvin Magic Johnson, Sheryl Swoopes, and other great players. At the heart of the game is the playing space and the equipment. The space is a rectangular, indoor court. The principal pieces of equipment are the two elevated baskets, one at each end (in the long direction) of the court, and the basketball itself. The ball is spherical in shape and is inflated. Basketballs range in size from in (7276 cm) in circumference, and in weight from 1822 oz (510624 g). For players below the high school level, a smaller ball is used, but the ball in men39。s games measures in (7576 cm) in circumference, and a women39。s ball is in (7274 cm) in circumference. The covering of the ball is leather, rubber, position, or synthetic, although leather covers only are dictated by rules for college play, unless the teams agree otherwise. Orange is the regulation color. At all levels of play, the home team provides the ball. Inflation of the ball is based on the height of the ball39。s bounce. Inside the covering or casing, a rubber bladder holds air. The ball must be inflated to a pressure sufficient to make it rebound to a height (measured to the top of the ball) of 4954 in ( m) when it is dropped on a solid wooden floor from a starting height of 6 ft ( m) measured from the bottom of the ball. The factory must test the balls, and the air pressure that makes the ball legal in keeping with the bounce test is stamped on the ball. During the intensity of high school and college tourneys and the professional playoffs, this inflated sphere mands considerable attention. Basketball is one of few sports with a known date of birth. On December 1, 1891, in Springfield, Massachusetts, James Naismith hung two halfbushel peach baskets at the opposite ends of a gymnasium and outlined 13 rules based on five principles to his students at the International Training School of the Young Men39。s Christian Association (YMCA), which later became Springfield College. Naismith (18611939) was a physical education teacher who was seeking a team sport with limited physical contact but a lot of running, jumping, shooting, and the handeye coordination required in handling a ball. The peach baskets he hung as goals gave the sport the name of basketball. His students were excited about the game, and Christmas vacation gave them the chance to tell their friends and people at their local YMCAs about the game. The association leaders wrote to Naismith asking for copies of the rules, and they were published in the Triangle, the school newspaper, on January 15,1892. Naismith39。s five basic principles center on the ball, which was described as large, light, and handled with the hands. Players could not move the ball by running alone, and none of the players was restricted against handling the ball. The playing area was also open to all players, but there was to be no physical contact between players。 the ball was the objective. To score, the ball had to be shot through a horizontal, elevated goal. The team with the most points at the end of an allotted time period wins. Early in the history of basketball, the local YMCAs provided the gymnasiums, and membership in the anization grew rapidly. The size of the local gym dictated the numbe