简述指数曲线法的概念要点。
参考答案：
指数曲线法（ExponentialcurvE.是一种重要的趋势外推法。当客观事物的指标或参数在散点图上的数据点构成指数曲线或近似指数曲线时，表明该事物的发展是按指数规律或近似指数规律变化。如果在给定期限内.有理由说明该事物仍将按此规律发展，则可按指数曲线外推预测。
一次指数曲线比较适合处于发生和发展阶段技术的预测，也可用于经济预测。
二次指数曲线和修正指数曲线则主要用于经济方面的预测。
指数曲线法的几个关键步骤包括：收集必要的数据、拟合曲线、趋势外推和预测说明。
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| Terry was a middle-aged leather trader whose repeated failure in career made him a depressed man, often 1 that he had been cheated by others. One day he told his wife he was so 2 with the city that he had to leave. So his family moved to another city. It was the evening of a weekend. When Terry and his wife were busily 3 up their new home, the light suddenly went out. Terry was regretful to have forgotten bringing along candles and had to wait 4 in a low mood. Just then he heard light, hesitant (犹豫的) knocks on his door that were clearly audible (听到) in the 5 night. "Who's it?" he wondered, since Terry was a 6 to this city. And this was the moment he especially hated to be 7 , so he went to the door and opened it 8 . At the door was a little girl, shyly asking, "Sir, do you have candles? I'm your neighbor." "No," answered Terry in anger and shut the door violently. "What a nuisance (讨厌)!" he complained over it with his wife. "No sooner had we settled down than the neighbor came to 9 things." After a while, the door was knocked again. He opened it and found the same girl outside. 10 this time she was holding two candles, saying, "My grandma told me the new neighbor downstairs might need candles. She 11 me here to give you these." Terry was very 12 by what he saw. At that moment he suddenly realized what caused his 13 in life. It was his 14 and harshness (刻薄) with other people. The person who had cheated him in life was 15 nobody else but himself, for his eyes had been blurred (蒙蔽) by his unsympathetic mind. | ||||
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