zh.wikipedia.org/wiki/%E6%9D%83%E8%AF%81
4 corrections found
认购权证价值与标的证券价格同向变化,当标的证券价格低于认购权证行权价格与行权手续费之和时,认购权证的价值为零。
认购权证的价格并不一定与标的证券严格同向变动;在到期前,即使处于价外,认购权证通常仍可能因时间价值而有正价格。
Full reasoning
HKEX 明确说明,权证价格不只受标的资产价格影响,还受波动率、剩余期限、供求等因素影响,因此“权证价格可能不按比例变动,甚至可能与标的资产价格走势相反”。HKEX 还专门举例:对认购证而言,若标的上涨,但隐含波动率下跌,认购证价格仍可能下跌;临近到期时,时间价值下降也可能抵消标的上涨带来的影响。
另外,把“标的价格低于行权价+手续费”直接等同于“认购权证的价值为零”也不对。ASX 的投资者教育材料写得很清楚:权证/期权的价格 = 内在价值 + 时间价值,而且在到期前,合约“通常会高于其内在价值交易”。也就是说,即便认购权证处于价外、内在价值为 0,在未到期时仍可能因为时间价值而有正价格。只有到期时仍然价外,它才会变得一文不值。
因此,这句话把“内在价值为零”误写成了“权证价值为零”,并且把认购权证与标的价格的关系说成了单向、必然的同向变动,二者都与交易所的投资者教育材料不符。
2 sources
- HKEX — Factors Affecting Pricing
Movements in the price of a derivative warrant may not be proportionate, or may even be opposite, to the price movement of the underlying asset... for a call warrant... the price of the call warrant may decrease... a decrease in time value may offset any increase in the price of the underlying asset.
- ASX — Pricing of options
Premium = intrinsic value + time value... Before expiry, an option often trades for more than its intrinsic value. The part of the premium over and above its intrinsic value is its time value.
认沽权证价值与标的证券价格反向变化,当标的证券价格高于认沽权证行权价格与行权手续费之差时,认沽权证的价值为零。
认沽权证的价格并不一定与标的证券严格反向变动;在到期前,即使处于价外,认沽权证通常仍可能因时间价值而有正价格。
Full reasoning
这句话和上一句对认购证的表述存在同样的问题。HKEX 说明,权证价格除标的资产价格外,还会受到波动率、剩余期限、供求等因素影响,因此价格变动不一定与标的价格成简单反向关系,甚至可能出现与直觉相反的走势。HKEX 还明确写道:对认沽证而言,时间价值的减少可能抵消标的资产下跌带来的利好,特别是在临近到期时。
同样,把“标的价格高于认沽权证行权价−手续费”直接说成“认沽权证的价值为零”也不准确。ASX 的教育材料指出,合约价格由内在价值和时间价值组成,而且到期前通常会高于其内在价值。因此,认沽权证即便处于价外、内在价值为 0,在未到期时也可能仍有正的市场价格;只有到期时仍然价外,才会失去全部价值。
所以,这里把“价外时内在价值为零”误写成了“整个权证价值为零”,并把认沽权证与标的价格关系简化成了必然反向,这与交易所公开资料不符。
2 sources
- HKEX — Factors Affecting Pricing
Movements in the price of a derivative warrant may not be proportionate, or may even be opposite, to the price movement of the underlying asset... in respect of a put warrant, a decrease in time value may offset any decrease in the price of the underlying asset.
- ASX — Pricing of options
Premium = intrinsic value + time value... Before expiry, an option often trades for more than its intrinsic value. The part of the premium over and above its intrinsic value is its time value.
V I ′ \= P V ( S T − X ) \= S − X e − r ( T − t ) {\\displaystyle V\_{I}'=PV(S\_{T}-X)=S-Xe^{-r(T-t)}}
把认购权证的“内在价值”写成 `S − Xe^{-r(T−t)}` 不对;标准定义下,内在价值应基于当前标的价格与行权价的差额,而不是把行权价折现。
Full reasoning
这条公式把“内在价值(intrinsic value)”与别的定价表达式混在了一起。FINRA 对 intrinsic value 的定义是:如果期权立刻到期、且标的停留在当前价格时,该合约的价值。ASX 也明确写道:内在价值是行权价与当前股价之间的差额,且不能小于零;对认购类合约,只有当当前股价高于行权价时才有内在价值。
因此,认购权证/认购期权的标准内在价值写法应是类似 max(S − X, 0)(若有换股比率等,再按条款调整),而不是 S − Xe^{-r(T−t)}。后者把行权价按无风险利率折现,已经不是“立刻到期、按当前价格衡量”的内在价值定义了。
新加坡权证教育材料也用同样口径说明:当认购权证的行权价低于标的当前股价时,它才具有内在价值;而且权证通常还会高于内在价值交易,因为还有时间价值。这些公开定义都与页面中的公式不一致。
3 sources
- FINRA — Options
Intrinsic Value: In relation to options, intrinsic value is the value of an option if it were to expire immediately with the underlying stock at its current price.
- ASX — Pricing of options
Intrinsic value is the difference between the option's exercise price and the current share price. It cannot be less than zero. Call options have intrinsic value if the share price is above the exercise price.
- Macquarie Singapore Warrants — Intrinsic & Time Value
When the exercise price of a call warrant is below the underlying’s current share price, it is said to have ‘intrinsic value’. All call warrants with an exercise price lower than the spot price should always be worth at least the intrinsic value.
V I ′ \= P V ( X − S T ) \= X e − r ( T − t ) − S {\\displaystyle V\_{I}'=PV(X-S\_{T})=Xe^{-r(T-t)}-S}
把认沽权证的“内在价值”写成 `Xe^{-r(T−t)} − S` 也不对;标准定义下,内在价值应基于当前行权价与当前标的价格的差额,而不是把行权价折现。
Full reasoning
这条认沽权证公式和上面的认购权证公式属于同一类错误:把“内在价值”写成了含折现项的表达式。FINRA 的定义是,内在价值指若合约立刻到期、标的维持当前价格时的价值。ASX 进一步说明,内在价值是行权价与当前股价之间的差额,且不能小于零;对认沽类合约,只有当当前股价低于行权价时才有内在价值。
所以,认沽权证/认沽期权的标准内在价值应是类似 max(X − S, 0)(再按换股比率等条款调整),而不是 Xe^{-r(T−t)} − S。把行权价折现后得到的量,并不符合交易所和监管机构对 intrinsic value 的常规定义。
同样,ASX 还指出期权/权证价格通常高于其内在价值,因为还有时间价值;这也说明“内在价值”本身是一个与当前价差相关的概念,而不是页面中给出的折现公式。
3 sources
- FINRA — Options
Intrinsic Value: In relation to options, intrinsic value is the value of an option if it were to expire immediately with the underlying stock at its current price.
- ASX — Pricing of options
Intrinsic value is the difference between the option's exercise price and the current share price. It cannot be less than zero... Put options have intrinsic value if the share price is below the exercise price.
- HKEX — Factors Affecting Pricing
Time value is the value of a derivative warrant arising from the time left to maturity and is equal to the difference between the current derivative warrant price and its intrinsic value.